Improving malaria treatment

"WHO (World Health Organization) is releasing the first ever guidance on procuring safe and efficient anti-malarial medicines. The guidelines will help countries select and obtain effective, good quality medicines and save lives by improving the way patients are diagnosed and treated" (WHO).

New guidelines recommend "the use of diagnostic tests and a new artemisinin-based combination therapy". Robert Newman, "director of the WHO global malaria" program, said "It is time to move away from the idea that everyone with a fever is suspected to have malaria" (Bernama).

Tests to determine whether or not malaria is the febrile culprit are necessary to prevent further drug-resistant malaria from developing. However, reliable tests are expensive and unavailable in rural villages, where they are most needed. "The WHO. . . recommended the rural health clinics, where microscopes are often unavailable, use Rapid Diagnostic Tests because they are easy for community health workers to handle" (Bernama).

"Each year there are 250 million cases of malaria and 860,000 deaths as a result. Approximately 85 percent of the deaths are children" (Bernama).

Malaria treatment guidelines: http://www.who.int/malaria/publications/atoz/9789241547925/en/index.html

Bernama. "WHO releases new malaria treatment guidelines." 10 March 2010. http://www.bernama.com/bernama/v5/newsworld.php?id=481148

WHO. "Improving malaria diagnosis and treatment." 09 March 2010. http://www.who.int/en/

Drug-resistant malaria

"In a dusty village near the Thai-Cambodia border, 24-year-old Oeur Samoeun sits on a dark green hammock recovering from a strain of malaria that has resisted the most powerful drugs available. . . Ravaged by days of fever and chills, he is considered lucky: the parasite has left his body. But for many others, the potentially deadly disease never quite disappears."

Pailin province, where Samoeun lives, is the unwitting nursery of drug-resistant malaria. It "is the epicenter of strains of malaria that have baffled healthcare experts worldwide, raising fears a dangerous new form of malaria could already be spreading across the globe."

Last year, a study published by the New England Journal of Medicine "showed that conventional malaria-fighting treatments derived from artemisinin took almost twice as long to clear the parasites that cause the disease in patients in Pailin and others in northwestern Thailand, suggesting the drugs were losing potency in the area." USAID, a U.S. development agency, agrees that traditional arteminsinin-based therapies are "now taking two to three times longer to kill malaria parasites along the Thai-Cambodian border than elsewhere."

Three drug-resistant malaria parasites have emerged from this province over the past five decades. "Thanks to prolonged civil conflict, dense jungles and movement of mass migrants in the gem mines in the 1980s and 90s, the strains multiplied and dispersed through Myanmar, India and two eventually reached Africa."

"Few can say why it is a hotbed for drug-resistant malaria", but experts point to "a combination of sociological factors and a complicated history spanning the Khmer Rouge era when 1.7 million people, nearly a quarter of Cambodia's population, perished from execution, overwork or torture during their 1975-79 rule."

Insurgents clung to Pailin, and it was "one of their last holdouts" before their defeat in the late 1990s. During the era of the Khmer Rouge, people resided in Pailin illegally. When they contracted malaria, they bought medication through black markets and self-medicated.

Self-medication was the only way to curb the rising number of malaria cases, so Cambodia made the decision to make anti-malarial drugs available over the counter. "The strategy carried risks. Easy access reduced the number of cases but also led to incorrect dosages and substandard or counterfeit medicine". Instead of eradicating the malaria parasites, over-the-counter treatments made the parasitic population stronger against widely used medications.

Without adequate drugs to combat the disease, drug-resistant malaria parasites threaten the world. Preventative measures, such as the use of bed-nets to avoid mosquito bites, may be our best defense against malaria. Donate a bed net through Nothing But Nets.

Source:
Win, Thin Lei. Reuters. "Cambodia drug-resistant malaria stirs health fears." 6 March 2010.

Malaria enters the US

"Nearly a dozen cases of Malaria has been confirmed here in the United States. All of the cases were acquired in Haiti after the January 12th, 2010 earthquake" (Gibbons). "Seven emergency responders, three Haitian residents now in the United States and one American traveler are known to have caught malaria in Haiti after the Jan. 12 earthquake, United States health officials said Thursday. Malaria is endemic throughout Haiti, so Haitians now living outdoors and relief workers are 'at substantial risk for the disease,' the Centers for Disease Control and Prevention said" (McNeil).

"Haiti already had a problem with malaria, which is spread by mosquitoes that will have more places to breed in the cities and towns wrecked by the giant quake" (Reuters). Displaced people living in temporary shelters our outdoors are at substantial risk of contracting malaria. Health workers who flooded to Haiti after the earthquake to offer aid are also at risk. "U.S. health officials advise people travelling to Haiti should take medications to prevent malaria" (UPI).

"Six out of eight patients, including seven emergency responders, had been advised to take drugs to prevent malaria but had not done so, the PAHO experts said." Three of the cases that the CDC cited "occurred among Haitian residents traveling to the United States and one case involved a U.S. resident who was visiting Haiti. All are expected to recover fully" (Reuters).

Individuals in Haiti are still at risk. "Each year, Haiti reports about 30,000 confirmed cases of malaria to the Pan American Health Organization, but the CDC estimates as many as 200,000 may occur each year. According to the CDC, malaria transmission peaks after the two rainy seasons -- November to January and again during May to June" (Reuters). The peak season is still months away, but anti-malarial medications are already needed to treat those who are infected and reduce the number of possible cases.

"There is no vaccine against the parasite that causes the illness[,] and it quickly evolves resistance against drugs"; however some drugs are known to treat and reduce malaria illness (Reuters).

The CDC indicates that "anyone traveling to Haiti should take drugs to help prevent infection" (Reuters).


Sources:
Gibbons, Sabrina. WSB News. "Malaria from Haiti Now in US." 4 March 2010.

McNeil, Donald G Jr. The New York Times. "U.S. Warns of Malaria Risk in Haiti". 4 March 2010.

Reuters. "Travelers from Haiti bringing Malaria to the US." 4 March 2010.

UPI. "Malaria Drugs for those going to Haiti." 4 March 2010.

Climate and behavioral change

In recent years, "malaria has been spreading into highland areas of East Africa, Indonesia, Afghanistan, and elsewhere" it was previously unknown. High elevations, low temperature, and temperate rainy seasons prevented malaria from entering these regions before. Now, the deadly disease is contracted locally in these previously malaria-safe environments. Malaria "is on the rise in some parts of the world" partly due to climate change. Other "factors such as migration and land-use changes are likely also at play."

"We assessed...conclusions from both sides and found that evidence for a role of climate in the dynamics is robust," write study authors Luis Fernando Chaves from Emory University and Constantianus Koenraadt of Wageningen University in the Netherlands. "However, we also argue that over-emphasizing a role for climate is misleading for setting a research agenda, even one which attempts to understand climate change impacts on emerging malaria patterns."

"Malaria, a parasitic disease spread to humans by mosquitoes, is common in warm climates of Africa, South America and South Asia." Development and survival of the mosquito and parasite depend on warm temperatures; therefore, "the disease has been spreading to the highlands, and many studies link the spread to global warming. But that conclusion is far from unanimous. Other studies have found no evidence of warming in highland regions, thus ruling out climate change as a driver for highland malaria."

Most studies, which conclude that climate change plays a significant role in highland malaria, tend to be statistically strong. Clearly, climate change does impact the range of malaria endemic regions; however, it may not be the only contributing factor. "What is needed, the researchers say, is a research approach that combines climate with other possible factors."

"Even if trends in temperature are very small, organisms can amplify such small changes and that could cause an increase parasite transmission," a researcher said. "More biological data will improve our overall understanding of malaria and will allow scientists to propose more general and accurate models on the impacts of climate change on malaria transmission."

Some factors contributing to the spread of malaria may be migration and agriculture. People "migrating from lowlands may be introducing the malaria parasite into highland regions. Changes in farming practices may also play a role. Irrigation associated with more intensive farming may be creating more places for mosquitoes to breed."

"The spread of malaria in highlands is of great concern to those who work to contain the disease. But understanding the many factors that influence the spread of highland malaria could help with efforts to control the disease worldwide."

Source:
University of Chicago Press Journals (2010, March 4). Climate change one factor in malaria spread. ScienceDaily. Retrieved March 4, 2010, from http://www.sciencedaily.com­ /releases/2010/03/100303162906.htm

Battling malaria

"Scientists battling malaria have earned a major victory", according to a Nature Genetics study. "Combating malaria resistance is nothing short of an arms race," says author and pediatrics professor, Dr. Philip Awadalla, from the Universite de Montreal. "As the malaria pathogen evolves, researchers must evolve with it to find ways to counter the disease."

Every year approximately 250 million people contract malaria. "Malaria is transmitted when people are bitten by infected mosquitoes. According to the World Health Organization, malaria symptoms include fever, headaches, vomiting and appear within 10 to 15 days after an infected mosquito bite." If left "untreated, malaria can be life-threatening" and may kill "an estimated five million people yearly." At the current level of malaria treatment one million people die annually, and most of those who die are young children.

The team at Universite de Montreal is deciphering the deadly parasite in an effort to eradicate the disease. This "international group of researchers has used genomics [study of organisms' genomes] to decode the blueprint of Plasmodium falciparum -- a strain of malaria most resistant to drugs that causes the most deaths around the world. The discovery may lead to advanced pharmaceuticals to fight the disease and prevent drug resistance".


"The team decoded 200 malaria samples from Asia, Africa, Central America, South America and Papua New Guinea. Their goal was to identify how Plasmodium falciparum strains were becoming resistant to the eight anti-malaria drugs currently available." The team noted how there is "substantial genetic differences in malaria around the world. What has occurred is a combination of genetic drift, where genes segregated over space and time from differential environments, immune pressures and exposures to drugs."

Research discovered that "Plasmodium falciparum recombined fastest in Africa...New clues garnered by this study...will allow pharmaceutical companies to create treatments that target the evolving malaria genome."

Sources:

Mu et al. Plasmodium falciparum genome-wide scans for positive selection, recombination hot spots and resistance to antimalarial drugs. Nature Genetics, 2010; DOI: 10.1038/ng.528

University of Montreal (2010, February 18). Genomic warfare to counter malaria drug resistance. ScienceDaily. Retrieved February 20, 2010, from http://www.sciencedaily.com¬ /releases/2010/02/100216140146.htm

King Tut's Curse

Celebrities draw attention to the diseases that ail them. This is true even if the celebrity is over three-thousand years old. Several media channels released reports pinning the death of King Tutankhamun, a famous pharaoh who died at a young age, on "a severe bout of malaria combined with a degenerative bone condition" (New York Times).

Results from the recent study of Tut's mummy show that he had several genetic bone disorders and that he was "afflicted with avascular bone necrosis, a condition in which diminished blood supply to the bone leads to serious weakening or destruction of tissue." In an already weakened individual, malaria is often fatal. "The finding led to the team's conclusion that it and malaria were the most probable causes of death" (New York Times).

Malaria was nearly impossible to escape during the time of King Tut. Mosquitoes bred in the Nile Valley, fed off whomever they encountered--royalty or not--and carried malaria. In modern times, approximately one million people die from malaria every year. Most of those who die are children, women, and already ill people. Today, a malaria-stricken individual can be treated for malaria. A variety of drugs combat the malaria parasites that cause illness in humans. Malaria can also be prevented through the use of insecticides, mosquito nets, and preventative medicines.


King Tut may not have been so lucky. While the pharaoh may have been able to hide from mosquitoes behind a bed net (a method of malaria prevention still used today), he did not have extensive medical treatments available to him--a fate that still befalls many today.


250 million cases of malaria are reported annually. Many of the humans who fall ill to malaria do not have the medical resources they need to survive. Over three-thousand years after Tut's death, people still suffer and die from malaria. But now, malaria is treatable and preventable. The problem is getting the necessary medical treatment to those in need.

My suggestion: Let the dead do what they do, and worry instead about the people dying today.


Support Roll Back Malaria and Malaria No More. Treating a bout of malaria costs under $5.00. A $10 bednet can save two lives.

Sources:
New York Times. Wilford, John Noble. "Malaria Most Likely Killed King Tut, Scientists Say." 16 February 2010.

Telegraph. Alleyne, Richard. "King Tut died of malaria and bone condition, says new research." 16 February 2010.

Credit: @followthethread deserves recognition for her alert. She's on my Do Not Bite list.

Photo source: Bjørn Christian Tørrissen (via wikimedia creative commons archives)

Chemical paths

Frequent use and misuse of antimalarials [drugs that fight malaria] can lead to malaria parasites that are resistant to existing treatments. For this reason, there "is an urgent need for new drugs to combat malaria". "Researchers report that they have discovered -- and now know how to exploit -- an unusual chemical reaction mechanism that allows malaria parasites and many disease-causing bacteria to survive."

The same research team from the University of Illinois, led by Eric Oldfield, developed an inhibitor of a pivotal chemical reaction. This inhibitor may fight malaria [and other bacterial and parasitic diseases] in a manner that is different from the traditional medicines. The situation is dire, according to Oldfield. "The parasites that cause malaria also have become resistant to quinine, chloroquine and now, artemisinin, three common treatments for the disease."

"The new study focuses on an essential chemical pathway that occurs in malaria parasites and in most bacteria but not in humans or other animals, making it an ideal drug target." An enzyme, known as IspH, promotes the assembly of a "class of compounds, called isoprenoids, which are essential to life" and prove to be necessary to the bacteria and parasites that cause disease.

"Isoprenoids are the largest class of compounds on the planet," Oldfield said. "There are over 60,000 of them. Cholesterol is an isoprenoid. The orange beta-carotene in carrots is an isoprenoid. And bacterial cell walls are made using isoprenoids." After a decade of research, scientists believe that they understand the structure and function of IspH and hope that it will "allow them to find a way to... shut down production of isoprenoids in the disease-causing bugs," thereby reducing their numbers.

"We're really at the initial, key stage, which is understanding structure and function and getting clues for inhibitors -- drug leads," he said. "But there are a finite number of proteins unique to bacteria and malaria parasites that can be targeted for the development of new drugs. And everyone agrees that this enzyme, IspH, is a tremendous target."

Further research:
Eric Oldfield et al. Bioorganometallic mechanism of action, and inhibition, of IspH. Proceedings of the National Academy of Sciences, Feb 15, 2010. http://www.news.illinois.edu/WebsandThumbs/Oldfield,Eric/0215pnas.200911087.pdf
The National Institute of General Medical Sciences at the National Institutes of Health funded this research.


Source:
University of Illinois at Urbana-Champaign (2010, February 16). New weapon to fight disease-causing bacteria, malaria developed. ScienceDaily. Retrieved February 16, 2010, from http://www.sciencedaily.com¬ /releases/2010/02/100215173944.htm

Photo source:
http://insciences.org/article_album_file.php?article_id=8350&articlemedia_id=1069

Substandard Medicines

"A high percentage of medicines circulating on national markets", in ten Sub-Saharan African countries, "are of substandard quality and thus may contribute to the growth of drug-resistant strains of Plasmodium falciparum, the most virulent form of malaria." First results of the "large-scale study of key antimalarial medicines" were released for Madagascar, Senegal, and Uganda by the Promoting the Quality of Medicines (PQM) Program, a USAID-funded program.

"Within Madagascar, Senegal and Uganda, the study" focused "on artemisinin-based combination therapy (ACT) products, currently the WHO's recommended form of first-line treatment for uncomplicated malaria, and sulfadoxine-pyrimethamine (SP) products, often used for preventative treatment of malaria during pregnancy." Researchers collected samples from "public and regulated private sectors" and from "informal markets, as many patients obtain their medicines from these sources."

"Substandard and counterfeit versions of antimalarial medicines are highly problematic throughout Africa, Asia and Latin America because of the direct threat they pose to the lives of individual patients as well as their contribution to the development of drug-resistant strains of these diseases." The "study found that approximately 44 percent of sampled medicines from Senegal, 30 percent of samples from Madagascar, and 26 percent of samples from Uganda that underwent full quality control laboratory testing failed such testing and were thus substandard."

"Substandard" medicines are classified as "those that do not meet the quality specifications set for them, primarily because they do not contain the correct amount of the active ingredient(s), do not dissolve properly in the body or include unacceptable levels of potentially harmful impurities." According to the released results, "[n]o samples in the full study completely lacked the active ingredient(s). The results also showed that, as a general rule, when a brand passed or failed in one country, it would also pass or fail in other countries. This indicates that the problem of quality is created at the source, rather than during passage through the distribution chain."

Substandard medicines were not limited to informal markets, and their point of sale varied by country. "In Madagascar, for instance, poor quality medicines appear to be widespread across regions and not limited to any particular type of distributor [public, private, or informal]. In Uganda, samples fared much better in the public sector than in the country's private sector. Despite overall failure rates, this was one of the bright spots the study revealed; in Uganda's public sector, all ACT and SP samples passed quality tests."

The purpose of this study was reveal "the prevalence of substandard antimalarials in Sub-Saharan Africa, which are believed to contribute to antimicrobial resistance of Plasmodium falciparum. Already, Plasmodium falciparum has become resistant to traditional" treatments "such as chloroquine, and more recently to SP products. The sustainability of treatment success depends to a large extent on preventing Plasmodium falciparum's exposure to incomplete doses of these medicines to minimize the possibility of the emergence of drug resistance."

Source:
US Pharmacopeia (2010, February 10). One-third of antimalarial medicines sampled in three African nations found to be substandard. http://vocuspr.vocus.com/vocuspr30/Newsroom/ViewAttachment.aspx?SiteName=USPharm&Entity=PRAsset&AttachmentType=F&EntityID=108111&AttachmentID=f2e22216-44a5-41a2-a9bc-464b7a98e3bf

Malaria vaccine to protect pregant women

"Each year, 25 million pregnant women in sub-Saharan Africa run the risk of contracting malaria." Women who become infected during their first pregnancy are at the most risk for severe anemia and poor fetal growth. "The malaria parasites accumulate in the placenta, resulting in children being born prematurely and underweight." Maternal malaria causes the death of approximately 200,000 infants and 10,000 women each year

"Researchers at the University of Copenhagen have become the first in the world to synthesize the entire protein that is responsible for life-threatening malaria in pregnant women and their unborn children. The protein known as VAR2CSA enables malaria parasites to accumulate in the placenta and can therefore potentially be used as the main component in a vaccine to trigger antibodies that protect pregnant women against malaria. The research team is now planning to test the efficacy of the protein-based vaccine on humans."

"The hope is that within 10 years all African girls could be vaccinated against maternal malaria, thereby preventing more than 200,000 deaths a year." The vaccine "elicits antibodies that stop the [malaria] parasite from binding to the placenta." Laboratory testing is underway, and the vaccine can already be tested in animals.

"These antibodies seem to be effective at preventing the parasite from accumulating in the placental tissue. The next step is to investigate whether we can elicit the same antibodies and so protect against the disease by vaccinating humans. Then the vaccine will be a reality."

Source:
University of Copenhagen (2010, February 5). Vaccine to protect pregnant women from contracting malaria?. ScienceDaily. Retrieved February 12, 2010, from http://www.sciencedaily.com­ /releases/2010/02/100204144433.htm

Pregnant women at risk

Pregnancy, for most women, means planning for a safe and healthy baby, but in malaria-endemic regions, fear of mortality outweighs hope. At "least 125.2 million women" who are at risk of contracting malaria "become pregnant each year".

Malaria during pregnancy creates disaster, causing "miscarriages, preterm births," low-birth-rate, and death. "About 10,000 women and 200,000 babies die annually because of malaria" during pregnancy. "Most malaria deaths are caused by Plasmodium falciparum, which thrives in tropical and sub-tropical regions", but "the most widespread type of malaria is P. vivax malaria, which also occurs in temperate regions." Estimates on the burden of malaria were previously only available for Africa", but now include lesser-realized endemic regions.

"The researchers estimated the sizes of populations at risk of malaria in 2007 by combining maps of the global limits of P. vivax and P. falciparum transmission with data on population densities. They used data from various sources to calculate the annual number of pregnancies (the sum of live births, induced abortions, miscarriages and still births) in each country. They calculated the annual number of pregnancies at risk of malaria in each country by multiplying the number of pregnancies in the entire country by the fraction of the population living within the spatial limits of malaria transmission in that country."

"This study contributes to the global understanding of the risk of malaria in pregnancy. In 2007, 54.7 million pregnancies occurred in areas with stable P. falciparum malaria and a further 70.5 million in areas with exceptionally low malaria transmission or with P. vivax only. This marks the first time species specific risks have been estimated globally for malaria in pregnancy."


Source:
Dellicour S, Tatem AJ, Guerra CA, Snow RW, ter Kuile FO. Quantifying the Number of Pregnancies at Risk of Malaria in 2007: A Demographic Study. PLoS Medicine, 2010; 7 (1): e1000221 DOI: 10.1371/journal.pmed.1000221

Lost Code

Although made of few parts, the complete DNA content or genome of a species is extensive and complicated. Plasmodium falciparum, "the most deadly form of malaria", has about 5,300 genes. "Up until now, scientists [had] a good understanding of the gene functions for only about half" of the genes.


Plasmodium falciparum is a tiny parasite that infects the blood of mammals through mosquito bites and is responsible for approximately 1 million human deaths each year. "Using transcriptional profiling," a process by which "gene expression (activity) patterns" are revealed, the research team lead by Prof Zbynek Bozdech (Nanyang Technological University) "has successfully uncovered the gene functions for almost the entire genome, with more than 90 percent of the gene functions from the previously unknown half now better understood."


"Transcriptional profiling is the measurement of the activity of thousands of genes at once," in order to "create a global picture of cellular function. These profiles can, for example, distinguish between cells that are actively dividing, or show how the cells react to a particular treatment. This outcome in infectious disease pathology could potentially be the decade's big breakthrough as it has yielded critical information about how the malaria parasite...responds to existing compounds with curative potential."


"Preventing malaria infection is important because resistance to anti-malaria drugs is a growing problem worldwide. There is currently no vaccine for malaria, which is widespread in poorer countries where it remains a hindrance to economic development. Also of growing concern to scientists is the confirmation of the first signs of resistance to the only affordable treatment left in the global medicine cabinet for malaria: Artemisinin."


"In successfully using transcriptional profiling to study the behavior of the malaria parasite, ...researchers have ventured into the unknown and paved the way for future breakthroughs in healthcare."

Sources:
Gastin, George. "GenomeGradient.jpg" [Photo hosted by wikimedia, shared under CC license] http://commons.wikimedia.org/wiki/File:Genome_gradient.jpg

Nanyang Technological University (2010, February 6). World's first in-depth study of the malaria parasite genome. ScienceDaily. Retrieved February 7, 2010, from http://www.sciencedaily.com /releases/2010/02/100205102607.htm

Protective immunity

Every year approximately a million people die from malaria, a treatable blood disease, and most of those who die are children under the age of five. "A new vaccine to prevent the deadly malaria infection has shown promise to protect the must vulnerable patients--young children--against the disease."

The results found by the international research team, led by the University of Maryland School of Medicine's Center for Vaccine Development (CVD) and the Malaria Research and Training Center at the University of Bamako in Mali, excites the medical community. "In a new study of the vaccine in young children in Mali, researchers found it stimulated strong and long-lasting immune responses. In fact, the antibody levels the vaccine produced in the children were as high or even higher than the antibody levels found in adults who have naturally developed protective immune responses to the parasite over lifelong exposure to malaria."

"In areas of the world such as Africa, where malaria is particularly rampant, the young are most vulnerable to the disease since they have not built up the same natural immunity as adults. A child dies of malaria every 30 seconds, according to the World Health Organization. There are about 300 million malaria cases worldwide each year, resulting in more than one million deaths, most of them African children."

Malaria is a parasite, "spread to humans through mosquito bites". At this time, "no approved vaccine to protect against the condition" exists, although "using bed nets or killing mosquitoes with insecticides can prevent infection. The parasite is treatable using medications, though drug resistance is a relatively common problem. Eradicating the disease has become a priority for scientists and health officials worldwide. An effective and broadly protective vaccine is a key step toward that goal."

This "vaccine, based on a single strain of the falciparum malaria parasite -- the most common and deadliest form of the parasite found in Africa -- targets malaria in the blood stage. The blood stage is the period after the mosquito bite, when the parasite multiplies in the blood, causing disease and death." Before this discovery, "other blood stage vaccines" existed, but none of them exhibited "the ability to prevent malaria disease."

In addition to preventing malaria, the vaccine (at all three tested doses) "proved to be safe and well tolerated" in each of the 100 Malian children administered with the drug. A new trial is already planned to test more subjects and to examine "whether the vaccine -- though it is based on a single strain of malaria -- can protect against the broad array of malaria parasites that exist."

Sources:
University of Maryland Medical Center (2010, February 6). New malaria vaccine is safe and protective in children, scientists find. ScienceDaily. Retrieved February 6, 2010, from http://www.sciencedaily.com­ /releases/2010/02/100203201425.htm

Lethal Weapon

"Mankind may finally have a weapon to fight two of the world's deadliest diseases." A new vaccine may prove to be a "lethal weapon against malaria" and cholera. Each year approximately a million people die from malaria and cholera sickens hundreds of thousands. Currently, "no FDA approved vaccine to prevent malaria, a mosquito-borne illness" exists. "Only one vaccine to fight cholera, a diarrheal illness that is common in developing countries and can be fatal" is on the market. "The lone vaccine is too expensive to prevent outbreaks in developing countries after floods, and children lose immunity within three years of getting the current vaccine."

Recently, a "University of Central Florida biomedical researcher has developed what promises to be the first low-cost dual vaccine against malaria and cholera."

Led by Henry Daniell, the "team genetically engineered tobacco and lettuce plants to produce the vaccine. Researchers gave mice freeze-dried plant cells (orally or by injection) containing the vaccine. They then challenged the mice with either the cholera toxin or malarial parasite…Untreated rodents contracted diseases quickly, but the mice who received the plant-grown vaccines showed long-lasting immunity for more than 300 days (equivalent to 50 human years)."

In addition to this vaccine, Daniell's lab has "created vaccines against anthrax and black plague that generated a congratulatory call from the top U.S. homeland security official and was featured on the Discovery Channel."

But, why lettuce? "Producing vaccines in plants is less expensive than traditional methods because it requires less labor and technology," Daniell said.

"We're talking about producing mass quantities for pennies on the dollar," he said. "And distribution to mass populations would be easy because it could be made into a simple pill, like a vitamin, which many people routinely take now. There is no need for expensive purification, cold storage, transportation or sterile delivery via injections."

"For Daniell, his research is more than his day job. His passion to find vaccines for the world's top 10 diseases as defined by the World Health Organization comes from growing up in India. He watched many of his childhood friends contract malaria, cholera and other diseases."

"I'm not done yet," he claims. "I still have more diseases to attack."

Source:
University of Central Florida (2010, January 27). New vaccine could be lethal weapon against malaria, cholera. ScienceDaily. Retrieved February 3, 2010, from http://www.sciencedaily.com¬ /releases/2010/01/100126101421.htm

Digestive enzymes

"Malaria causes more than two million deaths each year, but an expert multinational team battling the global spread of drug-resistant parasites has made a breakthrough in the search for better treatment" (McGill). Examining the way malaria parasites reproduce, a team led by John Dalton, has identified "a plan of attack" to develop new and urgently needed treatments, which combat malaria.

The secret lies in how the parasites propagate. "Malaria parasites live inside our red blood cells and feed on proteins". They break down the proteins to "use the proceeds (amino acids) as building blocks for their own proteins". Once they "a sufficient size they divide and burst out of the red cell, entering another and repeating the process until severe disease or death occurs."

Specialized digestive enzymes of the parasites "enable them to undertake this process." Researchers have now developed three-dimensional structures of these two enzymes and "demonstrated how drugs can be designed to disable the enzymes."

"By blocking the action of these critical parasite enzymes, we have shown that the parasites can no longer survive within the human red blood cell," Dalton explains. "The team is putting their findings into action immediately and is already pursuing anti-malarial drug development."

Publications: The discovery will be published in the Proceedings of the National Academy of Sciences, and is the result of collaboration including Australia’s Queensland Institute of Medical Research, Monash University and the University of Western Sydney, Wroclaw University of Technology in Poland and the University of Virginia in the U.S.

Read more about digestive enzymes and malaria

Source:
McGill University (2010, January 29). Breakthrough could lead to new treatment for malaria. ScienceDaily. Retrieved January 31, 2010, from http://www.sciencedaily.com¬ /releases/2010/01/100128165850.htm

Alarm amid medicine shortage

Kenya's rainy season is the most dangerous for contracting malaria, a deadly disease carried by mosquitoes, and children are the most susceptible. "A shortage of malaria drugs for children has hit hospitals as fears of an outbreak of the disease loom following heavy rains in various parts of the country."

"The Kenya Medical Supplies Agency said stocks of the drugs were running low, but were in the process of being procured and could be delivered by the beginning of February." The Chief executive, John Munyu, is hopeful that the crisis will be avoided because deliveries are continuing. He indicated that "adult malarial drugs are already being supplied after a reported shortage in parts of the country."

The minister of medical services, Anyang' Nyong'o, claims that "the shortage of drugs was caused by inadequate funding by the Treasury." The "budget for Health ministries was laughable when compared to that for the Ministry of Education", he says. This is not the first shortage that Kenya has suffered in recent years. Antibiotics used to treat cholera "were nearly exhausted due to last year's outbreak".

Still, Nyong'o is confident that disaster will be avoided. He says, "I do not envisage any crisis because the government is already adding stocks to what is already there in the health facilities. That is mere replenishment."

Ogo, Kenneth. "Children's malaria drugs run out." Daily Nation. 7 January 2010.

Critically weakened

What happens when a vampire does not feed on human blood?

If you believe the tales spun in Vampire Diaries, then the once-deadly creature becomes significantly weakened, looses the ability to affect the human brain, and is generally much less threatening than his human blood consuming counterpart. The same is true for the variety of parasite that Dr Andrea Crisanti is studying in an attempt to find a malaria vaccine.

Malaria, a mosquito-borne disease that affects 300-500 million people each year, is caused by infection with Plasmodium parasites. The deadly disease kills approximately one million people every year, most of whom are children and pregnant women, is treatable and preventable. The search for a malaria vaccine is well under way, but the "number of life cycle changes" that the parasites undergo increase "the challenges of malarial vaccine development." In other words, because the malaria parasites change and adapt rapidly, a workable vaccine is difficult to develop.

However, recent research by Crisanti and her colleagues "have found that weakened Plasmodium elicits a protective immune response." This means that clinically and genetically weakened parasites may be used for vaccine development. Crisanti's team targeted Plasmepsin 4, "a digestive enzyme that is critical for Plasmodium growth and survival within the host red blood cells." Research showed that parasites without the critical digestive enzyme "were significantly less virulent than their wild-type [define: normal] counterparts."

Furthermore, "infection with plasmepsin 4-deficient parasites, in contrast to infection with wild-type Plasmodium, did not induce cerebral complications", which means that infection with the weaker parasite produces a less severe illness than an ordinary malaria infection. Also, parasites without the digestive enzyme "induced strong protective immune responses against secondary immunization with wild-type Plasmodium." This weakened parasite may provide a model for comparing genetically-weakened malarial vaccines.

Dr. Crisanti and colleagues conclude that "it is possible, by engineered inactivation of parasite proteins, to generate attenuated blood stage parasites that are capable of inducing protective immunity against blood-stage infection. Such parasites should be powerful tools in elucidating parasite-derived factors that cause severe disease and should provide additional insight into factors that are required to induce protective immunity."

Source:
American Journal of Pathology (2009, December 31). Weakened Plasmodium generates protective immunity. ScienceDaily. Retrieved January 3, 2010, from http://www.sciencedaily.com¬ /releases/2009/12/091230193211.htm

Meddling with sex

Your mother may have told you that it's not nice to meddle in the business of others (especially when it's 'nasty business'), but when it comes to mosquitoes, meddling may offer very nice results. Imperial College recently released a report, entitled: "Meddling in mosquitoes' sex lives could stop the spread of malaria", revealing how a particular species of Anopheles gambiae has an easily disrupted sexual process, which when interrupted will prevent that mosquito from breeding.

"The new study focuses on the species of mosquito primarily responsible for the transmission of malaria in Africa, known as Anopheles gambiae. These mosquitoes mate only once in their lifetime, which means that disrupting the reproductive process offers a good way of dramatically reducing populations of them in Africa. When they mate, the male transfers sperm to the female and then afterwards transfers a coagulated mass of proteins and seminal fluids known as a mating plug" (Reeves). Prior to the release of this study, the purpose of this mating plug was misunderstood. Unlike similar substances in other species, the "male mating plug is not a simple barrier to insemination from rival males" (Imperial). Instead it is "essential for ensuring that sperm is correctly retained in the female's sperm storage organ, from where she can fertilise eggs over the course of her lifetime. Without the mating plug, sperm is not stored correctly, and fertilisation cannot occur" (Reeves).

"In Imperial's mosquito labs, the scientists showed it was possible to prevent the formation of the plug in males, and that this stopped them successfully reproducing with females" (Imperial). "In the future", researchers may "develop an inhibitor that prevents the coagulating enzyme doing its job inside male An. gambiae mosquitoes in such a way that can be deployed easily in the field -- for example in the form of a spray as it is done with insecticides". In this way, "we could effectively induce sterility in female mosquitoes in the wild. This could provide a new way of limiting the population of this species of mosquito, and could be one more weapon in the arsenal against malaria" (Reeves).

Sources:
Imperial College London. "Meddling in Mosquitoes' Sex Lives Could Help Stop the Spread of Malaria." ScienceDaily 22 December 2009. 27 December 2009 .
Reeves, Danielle. "Meddling in Mosquitoes' Sex Lives Could Help Stop the Spread of Malaria." Imperial College London. http://www.eurekalert.org/pub_releases/2009-12/icl-mim121609.php

Malaria in Zanzibar

Zanzibar, a" semi-autonomous region composed of two islands off the coast of Tanzania in East Africa," has "drastically reduced malaria" in the past decade. "Zanzibar's aggressive campaign against malaria has reduced infections from as much as 40 percent of its 1.2 million people to less than 1 percent." Recent concerns regarding the reintroduction of malaria to the region sparked a study that tracks the travel patterns of Zanzibar residents by their telephone reception.

"University of Florida researchers at work on a malaria elimination study in Africa have become the first to predict the spread of the disease using cell phone records." Without accessing personal information, "scientists analyzed more than 21 million calls to determine how often residents of Zanzibar travel and where they go." The researchers discovered that "short trips to Dar es Salaam on the Tanzanian mainland nearby, where malaria is relatively uncommon", dominated the travel patterns. "However, they also revealed that a few" Zanzibaris "travel back and forth from more distant areas of Tanzania where the risk of getting the disease is much higher -- posing the greatest threat to elimination."

"Most callers never left Zanzibar, which means they posed no threat of reintroducing the Malaria parasite...About 12 percent did leave the islands, but most of those only visited relatively safe Dar es Salaam, and usually for just one or two days at a time. However, a few hundred residents made trips to regions of western and southern parts of Tanzania, where as many as 40 percent of the residents have the malaria parasite."

Zanzibar has made huge advances against malaria in the past decade; however, those advancements may be reversed by reintroduction. Tanzania, including distant areas that are infected with malaria, must reduce malaria transmission in order to keep infections in Zanzibar low. With concerted effort across Tanzania, the country may eliminate malaria from within its borders.

Sources:
University of Florida. "Cell Phone Records Used to Predict Spread of Malaria." ScienceDaily 17 December 2009. 17 December 2009 .

Eco-epidemiology

Small bands of males chased game through the savannahs. Females dug along the forest edges for roots, and searched the bushes for edible berries. Humans lived in isolated groups, which constantly moved in search of better subsistence. Then around ten thousand years ago, human settlements sprouted in the plains. Flocks grazed in pastures and humans tended their fields. This social transition "from hunting to agriculture brought permanent settlements, domestication of animals, and changes in diet. It also brought new infectious diseases, in what scientists call an 'epidemiologic transition'" (University).

"Another of these" epidemiologic "transitions came with the Industrial Revolution. Infectious diseases decreased in many places while cancer, allergies and birth defects shot up" (University). Changes to the environment, including shifts in the variety and type of species in a location, cause the emergence of new diseases or the resurgence of old diseases that were once rare.

"Now, it seems, another epidemiologic transition is upon us. A host of new infectious diseases -- like West Nile Virus -- have appeared. And infectious diseases thought to be in decline -- like malaria -- have reasserted themselves and spread" (University). Humans across the globe are falling victim to malaria, an ancient infectious disease, which was once considered to be limited to isolated tropical regions.

According to Pongsiri, a scientist conducting research on the resurgence of infectious disease, the studies "show that emergence or reemergence of many diseases is related to loss of biodiversity." She asserts that this disturbing trend is "not just case-study specific". "Something is happening at a global scale" (University). For example, it is now known that malaria rises and spreads from deforestation. The clearing of forests results in changes to the watershed, including the creation of reservoirs where malaria-carrying mosquitoes can breed. Elevation in regional temperature due to pollution or deforestation can increase the potential habitat of the mosquitoes, causing the disease to spread.

"It is new to think about biodiversity -- and therefore, species and land conservation -- as integral to public health. Until recently, almost no epidemiologists, nor medical schools, were framing questions of human infectious disease prevention in terms of, say, habitat structure, promoting genetic diversity in non-human species, or protecting animal predators as ecosystem regulators. Human diseases, goes the conventional thinking, are best understood and treated by looking at humans."

"Now there is the beginning of a movement to bring epidemiology and ecology together," says Pongsiri.

More info: http://www.sciencedaily.com/releases/2009/12/091203132157.htm

Source:
University of Vermont. "Biodiversity Loss Can Increase Infectious Diseases in Humans." ScienceDaily 3 December 2009. 5 December 2009 .

World AIDS Day

"Malaria and HIV are two of the most devastating global health problems of our time. Together they cause more than 4 million deaths a year" (WHO). On this World AIDS Day, Infectious Bite looks at the relationship between malaria and HIV (the virus that causes AIDS), and discusses new research to treat co-infected (simultaneously infected with both diseases) individuals.

"Our current understanding of the human immune response to malaria and HIV leads us to expect that either infection might influence the clinical course of the other." Ordinarily, "infections are associated with at least a transient increase in HIV viral load" (measure of severity) and it is logical to assume that malaria accelerates "HIV disease progression." On the other side, "immune deficiency caused by HIV infection should, in theory, reduce the immune response to malaria parasitemia and therefore increase the frequency of clinical attacks of malaria" (Whitworth).

According to UNICEF, "HIV infection increases the incidence and severity of clinical malaria. In non-pregnant adults, HIV infection has been found to roughly double the risk of malaria parasitemia and clinical malaria...Although the effect of malaria on HIV has not been so well documented, some recent research is now adding to the growing body of evidence. Acute malaria infection increases viral load, and one study found that this increased viral load was reversed by effective malaria treatment. This malaria-associated increase in viral load could lead to increased transmission of HIV and more rapid disease progression, with substantial public health implications" (UNICEF).

Treatment of malaria is also complicated by HIV. "Artemisinin combination therapy has become the standard of care for uncomplicated malaria in most of Africa. However, there is limited data on the safety and tolerability of these drugs, especially in young children and patients co-infected with HIV" (Shereen). Recently, a "controlled trial was conducted" in Uganda consisting of "HIV-infected and uninfected children aged 4-22)." Participants were randomly designated to receive treatments of artemether-lumefantrine (AL) or dihydroartemisinin-piperaquine (DP). Both therapies were deemed "safe and well tolerated for the treatment of uncomplicated malaria in young HIV-infected and uninfected children" (Shereen).

In conclusion, co-infection of HIV and malaria fuels the spread of both diseases. HIV increases the severity of the episode and the patient susceptibility to malaria infection. Malaria increases the viral load of HIV, thereby elevating the risk of spreading HIV. "Co-infection might...have facilitated the geographic expansion of malaria in areas where HIV prevalence is high. Hence, transient and repeated increases in HIV viral load resulting from recurrent co-infection with malaria may be an important factor in promoting the spread of HIV in sub-Saharan Africa" (Abu). The connection between HIV and malaria also corresponds to the treatment of both diseases. Artemether-lumefantrine and dihydroartemisinin-piperaquine are safe for the treatment of malaria in HIV-infected children. It is also believed that the effective treatment of malaria within HIV-infected individuals may reverse the increased viral load of co-infected individuals.

SOURCES:
Abu-Raddad, Laith J. Et. Al. "Dual Infection with HIV and Malaria Fuels the Spread of Both Diseases in Sub-Saharan Africa". Science 8 December 2006.

Shereen, Katrak Anne. Et al. Malaria Journal 2009, 8:272
UNICEF. "Malaria and HIV/AIDS." http://www.unicef.org/health/files/UNICEFTechnicalNote6MalariaandHIV.doc

Whitworth, James. HIV InSite Knowledge Base Chapter. May 2006. http://hivinsite.ucsf.edu/InSite?page=kb-05-04-04

WHO. http://apps.who.int/malaria/malariandhivaids.html

Pirate parasites

Parasitic Plasmodium invaders swarm the bloodstream, set up a base camp in the liver, and commandeer healthy red blood cells. These parasites "enter the body from the saliva of a mosquito" and send plague upon their victim (American). Malaria, the deadly and devastating disease that kills nearly a million people every year, is caused by the Plasmodium parasites as they pillage the human body for their own reproduction and survival.

"Inside the blood cells" of the malaria patient, "the parasites replicate and also begin to expose adhesive proteins on the cell surface that change the physical nature of the cells in the bloodstream" (American). Medical experiments "show that infected red blood cells are stiffer and stickier than normal ones." In "later stages of the disease" the cells can be "up to 10 times stiffer" than healthy red blood cells. These infected cells may also anchor onto "endothelial cells lining the vasculature, affecting the normal blood flow. This explains some of the common symptoms of malaria, such as anemia and joint pain" (American).

The parasites avoid a whirlpool of blood cell death in the spleen by anchoring in the safe harbors of the blood vessels. "Sticking to the walls of blood vessels is a survival mechanism for the parasite. In order to develop completely, it needs several days inside a red blood cell. Even though parasitized cells are nearly invisible for the immune system, they may be destroyed in the spleen while circulating freely in the bloodstream" (American).

Brown University professor George Karniadakis and student Dmitry Fedosov study "how malaria infections affect the physical properties of red blood cells, and alter normal blood flow circulation. In particular, they examine an increase in blood flow resistance, and dynamics of infected cells in the bloodstream." The properties that they measure are "used in modeling the flow of red blood cells in people infected with malaria" (American).

Fedosov says, "Our model predicts the dynamics of malaria-infected RBCs in the bloodstream, which anticipates the possible course of the disease." Each infected human contains a slightly different map and provides a unique environment that the parasites must navigate. The researchers recently discovered "that temperature fluctuations of infected red blood cell membranes measured in experiments are not directly correlated with the reported cell properties, hence, suggesting significant influence of metabolic processes" (American).

Hypothesizing on the metabolic processes that affect the patients' body temperatures, the researchers "measured an increase in resistance to blood flow in the capillaries and small arterioles during the course of malaria and found that parasitized red blood cells have a "flipping" motion at the vessel wall that appears to be due to stiffness of the infected cells. The developed models will aid to make realistic predictions of the possible course of the disease, and enhance current malaria treatments" (American).

Play the parasite game (NobelPrize.org site), and see if you can navigate your way to the liver.

Sources:
American Institute of Physics. "Measuring and Modeling Blood Flow in Malaria." ScienceDaily 22 November 2009. 27 November 2009 .

Call to action

"In this week's PLoS Medicine, the journal's editors call for concerted international action to address the crisis of malaria drug shortages across Africa." Compared to activism for many other causes, anti-malaria offensives are still developing to find novel ways to fight the disease. Editors reveal the signs of "an evolving 'malaria activism' (akin to AIDS activism)" (Public). "Probably no other disease in human history has been associated with social and political activism to the extent that the HIV epidemic has" (AIDS Activism). "Such activism played a huge role in reducing the costs of antiretroviral drugs in developing countries" (PLoS). Five years ago, a strong voice "argued that similar activism was needed to raise awareness of shortfalls in global efforts to control malaria" (Yarney). "We believe there are now signs of an evolving "malaria activism," which has resulted in two major successes" (PLoS). These outspoken agents assert that two waves of malaria activism have already occurred, and that we stand on the break of a third wave which will help deliver life-saving drugs to those who need them.

According to the medical journal, the "first wave of malaria activism highlighted the gap between the huge burden of malaria and the tiny amount of international development assistance dedicated to its control. Such advocacy helped motivate donors to increase their malaria commitments." The second wave of activism "focused on making sure that the extra funding was used to purchase" combination therapy drugs (like artemisinin combination therapies) that are more effective in Africa than single drug therapies (like cholorquine).
"These are big victories," the editors declare. "But one benchmark of successful ACT [Artemisinin Combination Therapy] scale-up is whether the drugs are available at the point of care. One of us has just returned from a health reporting fellowship in East Africa, where he found that ACT 'stock-outs' (shortages) were common." This crisis is due in part to "inadequate funding" to purchase the necessary combination therapies, "delays in procuring the drug, and weak health information systems that can't properly track national drug needs and flows".
The editors of the medical journal call for action. It is time for a third wave of activism. This new wave will raise awareness of the shortages of necessary drugs in regions of the world where they are desperately needed.

Sources:
AIDS Activism. http://www.albany.edu/sph/AIDS/activists.html

PLoS. "Time for a Third Wave of Malaria Activism." http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1000188

Public Library of Science. "It's Time for a 'Third Wave' of Malaria Activism to Tackle Drug Shortages." ScienceDaily 23 November 2009. 24 November 2009 .

Yarney, G. "Roll Back Malaria." http://www.plosmedicine.org/article/findArticle.action?author=Yamey&title=Roll%20Back%20Malaria:%20A%20failing%20global%20health%20campaign.

Male infertility

How does male sterility combat malaria? When mosquitoes are sterile, they devastate the entire mosquito population. Called the Sterile Insect Technique (SIT), "the release of sexually sterile male insects to wipe out a pest population" is suggested as a "solution to the problem of malaria in Africa" (BioMed).

Malaria "control in sub-Saharan Africa, where 90 percent of the 300 to 500 million malaria cases and one to three million deaths occur from malaria each year, still depends on only two technologies for vector intervention: indoor residual spraying and insecticide-treated bed nets" (Klassen). Overtime mosquitoes become resistant to pesticides and insect populations bounce back from elimination efforts. According to researcher, Mark Benedict, "In the context of elimination, SIT could play a unique role. As part of an area-wide integrated pest management programme, the SIT may be able to minimize problems due to insecticide resistance to antimalarial drugs" (BioMed).

This technique "involves the generation of 'sterile' male mosquitoes, which are incapable of producing offspring despite being sexually active. Because female mosquitoes only mate once during their lifetimes, a single mating with a sterile male can ensure that she will never breed" This leads to an increasing reduction in the population over time, in contrast to insecticides, which kill a certain fraction of the insect population" (BioMed).

Considerable "research and development on the suppression of mosquitoes with the sterile insect technique (SIT) was conducted from the mid-1950s to the mid-1970s"; however, "nearly all of the scientists who pioneered this approach have retired and several of the greatest have died." The resurgence of this idea is due in part to "new technologies" that are "available to support area-wide integrated pest management (AW-IPM) programmes" (Klassen).

If implemented in Africa, the sterile insect technique when combined with other measures could effectively eliminate the malaria-carrying mosquito population in Africa.

For an overview of the history of malaria and the SIT project, please read the study's introduction in the malaria journal: http://www.malariajournal.com/content/8/S2/I1

Sources:
BioMed Central. "Are Sterile Mosquitoes the Answer to Malaria Elimination?." ScienceDaily 17 November 2009. 18 November 2009 .
Klassen, Wauldemar. "Introduction: development of the sterile insect technique for African malaria vectors". Homestead, Florida. 16 November 2009.

Malaria in Vanuatu

"Vanuatu, an archipelago of over 80 islands in the South Pacific, ranks behind only the Solomon Islands for having the highest rate of malaria infections. Malaria in Vanuatu has been getting steadily worse since the 1980s, which is why UCSF scientists are among the medical professionals working hard to control malaria in this region" (UCSF).

Malaria parasites are found in all regions of Vanuatu, and "[t]ransmission occurs from December to May. Either mefloquine (Lariam), atovaquone/proquanil (Malarone), or doxycycline may be given. Mefloquine is taken once weekly in a dosage of 250 mg, starting one-to-two weeks before arrival and continuing through the trip and for four weeks after departure." Malarone is a "combination pill taken once daily with food," the side-effects of which are "typically mild". Doxycycline "is effective," against malaria in Vanuatu "but may cause an exaggerated sunburn reaction, which limits its usefulness in the tropics" (MD Health). It is important to know that "Chloroquine is NOT an effective antimalarial drug in Vanuatu and should not be taken to prevent malaria in this region" (CDC). Malaria resistance to Chloroquine is becoming increasingly throughout the world as the parasite adapts.

"UCSF researchers, with funding from the Bill and Melinda Gates Foundation", "are conducting a large-scale household-level survey of malaria treatment and prevention practices in Vanuatu. Over 900 households on four islands (out of a total of more than 80, although only a few are populated) have participated in the study. Researchers also collected blood samples from all members of the households selected for the survey, which will permit them to link survey responses on prevention and treatment practices to biological markers" (UCSF).

For more information on the study, please visit UCSF web page.

Sources:
CDC. Malaria in Vanuatu. http://wwwnc.cdc.gov/travel/destinations/Vanuatu.aspx

MD Travel Health. 'Vanautu'. http://www.mdtravelhealth.com/destinations/oceania/vanuatu.php

UCSF. Malaria Prevention. http://medschool.ucsf.edu/news/features/public_service/20060619_Malaria.aspx

Vaccine trials

Raise your hand if you took note of the press release regarding the malaria vaccine to jump at the chance to announce it before me. I see you there, sitting alone, sheepishly raising your hand. Actually, I'm quite proud of you. You're paying attention, spreading the word, and enlightening the world. Raise your hand higher, be proud! Oh wait. You in the public library: Put your hand down. People can see you.

So why is Ana so late to the party? No one told me the media gods were releasing the news today. I'm not psychic, you know. Also, I was preoccupied with public transit issues. Don't ask...

Of the emails and messages I received from avid followers, these are my favorites:
Can this really be true? Yaa!
Vampire fans -- this could be a breakthough.
Look [link] Why haven't you written yet? Did you get staked?

Calm yourselves, people. I'm not hindered by the strike of a little stake. The picketing version may be a different story, however.

Now that I'm back online, let me abbreviate the news:

"A pivotal efficacy trial of RTS,S, the world's most clinically advanced malaria vaccine candidate, is now underway in seven African countries: Burkina Faso, Gabon, Ghana, Kenya, Malawi, Mozambique and Tanzania" (PATH). This vaccine is the first to be designed specifically for malaria in Africa. Trials are being conducted in seven countries and different regions "across Sub-Saharan Africa" in order "to evaluate the vaccine candidate's efficacy in a variety of settings, with diverse patterns of malaria transmission. For example, some trial sites are located in areas where there is a year-round threat of malaria, while others experience only seasonal transmission". "The vaccine profile is intended primarily for infants, as they and children under the age of five are the most vulnerable to malaria" (PATH).

Previous research "studies showed that RTS,S reduced clinical episodes of malaria by 53 percent over an eight-month follow-up period" (PATH). Phase III trials are being conducted in what is now "the largest trial ever conducted in Africa of a vaccine specifically designed for use with African children."

Sources:
PATH Malaria Vaccine Initiative (2009, November 3). World's Largest Malaria Vaccine Trial Now Underway In Seven African Countries. ScienceDaily. Retrieved November 3, 2009, from http://www.sciencedaily.com¬ /releases/2009/11/091103102248.htm

Antimalarial side effects

In early October, a study comparing the side effects of commonly prescribed malaria medication was conducted by a team led by Dr. Frederique Jacquerioz at Tulane University. "The review looked at eight clinical trials" of commonly prescribed anti-malarials. Both "atovaquone-proguanil -- sold under the brand-name Malarone -- and doxycycline appear to have fewer side effects" than the other drugs tested. "With these two drugs, there is lower risk of nausea, stomach pain and other gastrointestinal side effects, and also neurological and psychiatric side effects, such as dizziness, sleep disturbances, anxiety and depression."

No drugs produced side effects that were considered life-threatening or required hospitalization; however, the investigators did discover a disturbing link between mefloquine and patient death. They uncovered "published case reports linking mefloquine to 22 deaths, including five suicides." It is important to note that "no other anti-malaria drugs have been linked to deaths when taken at prescribed doses".

Mefloquine is still an effective anti-malarial and may be safely prescribed to patients who have previously taken it without adverse effects. Doctors believe that risk of death is higher for patients who fail to take mefloquine when they should than the risk of serious side effects.

"[S]evere reactions to mefloquine are rare, noted Dr. Andrea Boggild of Toronto General Hospital in Canada, who was not involved in the study. In a written statement, Boggild said that severe neurological and psychiatric symptoms develop in just one out of every 6,000 to 10,000 people who take the drug."

In regard to antimalarial side effects, the Jacquerioz says this: "The main message is that you have to take some malaria chemoprophylaxis (preventive treatment) if you go to an endemic area". Malaria kills approximately one-million people each year, and an estimated ten-thousand to thirty-thousand travelers develop malaria annually.

"Boggild advised people who are planning a trip to a malaria-endemic area to talk with a healthcare provider who specializes in travel medicine about how to best protect themselves."

Source:
Reuters Health. " Two anti-malaria drugs have fewer side effects". Wednesday, October 7, 2009.

The Democratic Republic of the Congo

"The people of the Democratic Republic of the Congo desperately need help. People are dying every day from diseases we can prevent and treat" (WHO, Donor). Malaria is one of the biggest killers in the Democratic Republic of the Congo (formerly known as Zaire). "Health experts estimate that each child under five years of age in DRC has 6 to 10 attacks of malaria per year. This is equivalent to as many as 100 million episodes, or even more, annually. Approximately 180,000 Congolese children under five die from the disease every year, and many others are orphaned when malaria weakens and kills their parents" (Gilliam).

"In less than five years, more than 3 million people have died - most from preventable and treatable diseases. The public health infrastructure is virtually broken down. The risk of epidemics remains high. Without international support to restore basic health care services, the humanitarian crisis in the Democratic Republic of the Congo will only continue to worsen" (WHO, Donor). The country's health system "is severely weakened with insufficient capacity to meet the needs of the population...In many areas, the health system functions as if it were private and patients cannot afford to seek assistance. Numerous private pharmacies provide drugs of dubious quality." Furthermore, most "health workers have not received salaries...for decades. Doctors have left the periphery and gone to the cities or to international agencies for employment...The health worker education system does not function anymore, and there are concerns about the staff qualifications" (WHO, Country).

Current estimates report that "6 out of 10 children do not reach their 5th birthday" (WHO, Donor). "Malaria (P. Falciparum) is endemic" in the country "and is accountable for 45% of childhood mortality. Children under five, of whom only an estimated 0.7% sleep under an insecticide-treated net, suffer from six to ten malaria-related fever episodes each year" (WHO, Country).

"With the rainy season just days away, UNICEF, along with partners including UNITAID and the World Food Program, is mobilizing the distribution of some 5.5 million mosquito bed nets in DRC. Each has been treated with insecticide and can help reduce the risk of contracting malaria for those who sleep under them at night" (Gilliam).

The people of the Democratic Republic of the Congo need your help. While Non-governmental organizations and charities are donating and distributing mosquito nets to the country, the need is still great. Visit one of the sites below for information on how you can help send mosquito nets to people in need in the Democratic Republic of the Congo. Also, visit our Help Us page for information on how you can help Infectious Bite raise malaria awareness.

Links:
Malaria No More
Netting Nations

Sources:
Gilliam, Eva. UNICEF. "Malaria campaign underway in Democratic Republic of Congo" 5 October 2009.

WHO. Country Profile: DRC. http://www.who.int/hac/crises/cod/drc_profile_dec08.pdf
WHO. Photo Gallery. [Photo]
WHO. Donor Profile: DRC. http://www.who.int/hac/donorinfo/campaigns/cod/en/

Genetic Diversity

"Scientists and health officials worldwide have made eradication of" malaria "a priority, with an effective and broadly protective vaccine a critical step toward that goal. Malaria -- a parasite spread to humans through mosquito bites -- is prevented by avoiding mosquito bites using bed nets or by killing mosquitoes with insecticides. The parasite is treatable using medications, although drug resistance is a relatively common problem. According to the World Health Organization, a child dies of malaria every 30 seconds" (University). Currently, "no approved vaccine for malaria" exists, but "various experimental vaccines are in development" (University). As of now, "vaccines directed against the blood stages of Plasmodium falciparum malaria [a deadly strain] are intended to prevent the parasite from invading and replicating within host cells. No blood-stage malaria vaccine has shown clinical efficacy in humans" (Takala).

"Researchers at the University of Maryland School of Medicine Center for Vaccine Development (CVD) have charted the extreme genetic differences that occur over time in the most dangerous malaria parasite in the world" (University). They "examined the extent and within-host dynamics of genetic diversity in the blood-stage malaria vaccine" and concluded that this "extreme diversity may pose a serious obstacle" to the creation of an effective vaccine.

"The CVD study suggests that developing a broadly protective vaccine for malaria may be challenging because the parasite's genetic makeup is so variable, constantly changing" (University).

Sources:
Takala, Shannon L. et al. "Extreme Polymorphism in a Vaccine Antigen and Risk of Clinical Malaria: Implications for Vaccine Development." Sci Transl Med 14 October 2009:
Vol. 1, Issue 2, p. 2ra5.

University of Maryland Medical Center. "Extreme Genetic Variability In Malaria Parasite Found." ScienceDaily 15 October 2009. 21 October 2009 .

Malaria & Climate Change

Update on climate change as it relates to malaria (4 March 2010)

Every year approximately one million people die from malaria, and most of those are children. 350-500 million people are infected annually. This blood parasite is spread through the bite of infested mosquitoes and most frequently occurs within tropical regions. However, "malaria is an extremely climate-sensitive" disease that cannot be contained to the tropics (Patz). Medical researchers warn about the global threat of malaria in the future due primarily to climate change.

Climate change threatens to expand the mosquito's habitats, thereby spreading the disease. A joint study by the State University of New York and the Kenya Medical Research Institute showed that changes "in temperature can affect the development and survival of malaria parasites and the mosquitoes that carry them...Rainfall also influences the availability of mosquito habitats and the size of mosquito populations, the research found" (Barclay). A study conducted by Brown University researchers revealed that "an epidemic in Ethiopia was attributed to higher temperatures, rainfall and relative humidity than in previous years" (Brown).

A research team at University of Michigan (lead by M Pascual) has "documented a warming trend in the East African highlands from 1950 to 2002, concomitant with increases in malaria incidence. Moreover, their findings confirm the importance of the well recognized nonlinear and threshold responses of malaria (a biological system) to the effect of regional temperature change...For example, showing that the biological response of mosquito populations to warming can be more than an order of magnitude larger than the measured change in temperature represents a stunning finding, critical in advancing risk assessment of climate change impacts" (Patz).

[UNEP projected malaria distribution]

Outside of Africa, malaria is moving to higher altitudes and colder regions within endemic areas. "Malaria cases have been reported on the Bolivian high plateau," (Pabon). These individuals contracted the disease locally, meaning that malaria-carrying mosquitoes are now present in a region where they were previously unknown.

The US and UK are also under threat by malaria. Outbreaks of malaria within the US are not unknown, and may continue to increase as climates change. Florida and Louisiana are particularly susceptible to the disease. Across the pond, the UK reported 1370 cases of malaria in 2008. Six deaths were officially blamed on malaria (HPA). "A high likelihood of a major heat wave" may lead "to as many as 10,000 deaths, hitting the UK by 2012" warns the government (Prince). In coming years "the UK is to be hit by regular malaria outbreaks, fatal heat waves and contaminated drinking water within five years because of global warming, the Government has warned the NHS [National Health Service]" (Prince).

"The best climate conditions for malaria are a long rainy season that is warm and wet, followed by a dry season that is not too hot, followed by a hot and wet short rainy season," (Barclay). Pure global warming is not the primary culprit, instead a general shift in climate across regions is feared. Malaria is a devastating disease that infiltrates all areas of life. Epidemics destroy the health, economy, and cultural fabric of regions where malaria is prevalent.

We can make adjustments in our lives to prevent climate change; however, we also need to attack malaria to prevent its spread. Help Infectious Bite stop malaria in its tracks by supporting our cause or by donating to one of the many reputable agencies that provide mosquito nets and medicine to people threatened by malaria. Together we can Bite Malaria Back.

Sources:
Barclay, Eliza. " Climate Change Fueling Malaria in Kenya, Experts Say..." National Geographic. 9 January 2008.

Brown University. "Climate Change and Malaria". http://www.brown.edu/Research/EnvStudies_Theses/full9900/creid/climate_change_and_malaria.htm

Pabon, Cristina. Malaria spreading on Bolivian High Plains. SciDevNet.

Patz, Jonathan A. Sarah H Olson. "Malaria risk and temperature…" PNAS.

Prince, Rosa. "Malaria Warning as UK becomes warmer." Telegraph.co.uk. 12 Feb 2008.

UNEP: Map (http://maps.grida.no/go/graphic/climate_change_and_malaria_scenario_for_2050)

Poetry

"MALARIA" [trans. by Laurence Hope]

He lurks among the reeds, beside the marsh,
Red oleanders twisted in His hair,
His eyes are haggard and His lips are harsh,
Upon His breast the bones show gaunt and bare.

The green and stagnant waters lick his feet,
And from their filmy, iridescent scum
Clouds of mosquitoes, gauzy in the heat,
Rise with His gifts: Death and Delirium.

His messengers: they bear the deadly taint
On spangled wings aloft and far away,
Making thin music, strident and yet faint,
From golden eve to silver break of day.

The baffled sleeper hears th' incessant whine
Through his tormented dreams, and finds no rest.
The thirsty insects use his blood for wine,
Probe his blue veins and pasture on his breast.

While far away He in the marshes lies,
Staining the stagnant water with His breath,
An endless hunger burning in His eyes,
A famine unassuaged, whose food is Death.

He hides among the ghostly mists that float
Over the water, weird and white and chill,
And peasants, passing in their laden boat,
Shiver and feel a sense of coming ill.

A thousand burn and die; He takes no heed,
Their bones, unburied, strewn upon the plain,
Only increase the frenzy of His greed
To add more victims to th' already slain.

He loves the haggard frame, the shattered mind,
Gloats with delight upon the glazing eye,
Yet, in one thing His cruelty is kind,
He sends them lovely dreams before they die;

Dreams that bestow on them their heart's desire,
Visions that find them mad, and leave them blest,
To sink, forgetful of the fever's fire,
Softly, as in a lover's arms, to rest.

"Malaria". India's Love Lyrics. Trans. Laurence Hope. New York: John Lane Co., 1906.

Fungus reduces malaria transmission

"Biopesticides containing a fungus that is pathogenic to mosquitoes may be an effective means of reducing malaria transmission, particularly if used in combination with insecticide-treated bednets" (Public). Mosquito adaptation and resistance to insecticides is a major hindrance to malaria eradication. "In developing strategies to control malaria...there is increased interest in biological methods that do not cause instant" mosquito or parasite death. Instead, scientists are searching for preventative measures, which "have sublethal and lethal effects at different ages and stages in the mosquito life cycle", with the hope that these more mild approaches will be more effective in the long run than the aggressive techniques used in the past. (Hancock).

"[A]ccording to a modelling study conducted by Dr. Penelope Hancock from Imperial College London," incorporating fungal biopesticides "may substantially reduce malaria transmission rates and help manage insecticide resistance...Efficient combinations of interventions may allow each to be used at lower levels, and slow the development of resistance in the mosquito population" (Public).


Sources:
Hancock, Penelope A. "Combining Fungal Biopesticides and Insecticide-Treated Bednets to Enhance Malaria Control".

Public Library of Science. "Control Of Mosquito Vectors Of Malaria May Be Enhanced By A New Method Of Biocontrol." ScienceDaily 1 October 2009. 7 October 2009 .

Popcorn parasite

Who would have thought that infecting "mosquitoes with a bacterial parasite could help prevent the spread" of blood parasites like malaria and lymphatic filariasis? If you guessed that it might, then you are either clever or very well-informed. For the rest of us, it is an exciting idea that may aid in "the control of...mosquito-borne parasites" (Wellcome).

Researchers have infected mosquitoes with a strain of Wolbachia, which is a bacterial parasite that infects insects and other arthropod species (Werren). The strain known as wMelPop, and nicknamed 'popcorn', can halve the lifespan of infected mosquitoes. "Mosquito-borne parasites such as the filarial nematode or the malaria parasite require an incubation period between ingestion and transmission, so only older mosquitoes" are "infective. Skewing the mosquito population towards younger individuals reduces the number of infectious insects." In the case of lymphatic filariasis, a parasitic worm that is transmitted by mosquitoes, wMelPop has also been shown to encourage "the mosquito's immune system to attack" the parasite that it hosts (Wellcome).

The 'Popcorn' strain may reduce the number of mosquitoes and the likelihood that they will transmit a parasite that is deadly to humans. Researchers are "currently looking at whether infecting other species of mosquito, such as Anopheles gambiae - the mosquito responsible for the majority of malaria infections - with wMelPop will have a similar effect and help inhibit malaria transmission as well as filariasis transmission."


Sources:

Kambris Z et al. Immune activation by life-shortening Wolbachia and reduced filarial competence in mosquitoes. Science 2009.

Wellcome Trust (2009, October 2). Parasite Bacteria May Help Fight Spread Of Mosquito-borne Diseases. ScienceDaily. Retrieved October 4, 2009, from http://www.sciencedaily.com­ /releases/2009/10/091001163601.htm

Werren, J.H.; Guo, L; Windsor, D. W. (1995). "Distribution of Wolbachia in neotropical arthropods". Proc. R. Soc. London Ser. B 262: 147–204.

African Leaders Malaria Alliance

"Malaria is one of the biggest killers of African children." Recently, "African leaders have begun an ambitious program to eliminate nearly all malaria deaths in Africa over the next six years." Initiated by Tanzanian President Jakaya Kikwete, the African Leaders Malaria Alliance was established "to streamline the procurement and distribution of control and treatment methods while keeping the disease high on the international development agenda" (Scott). "The international community has already donated more than $3 billion to the project, the BBC reports, adding, "The money will pay for the distribution of 240 million insecticide-treated bed nets throughout sub-Saharan Africa by the end of next year" (Nyaria).

"Africa is the continent most affected by malaria, accounting for 86 percent of all cases and 91 percent of all malaria deaths worldwide" (Henry). The statistics are sobering. "Nearly twenty percent of African women who die in childbirth" suffer "from malaria. It accounts for one-quarter of all deaths of children under five" (Scott). Every year, nearly a million people die.

The goal of the alliance "is to provide universal access to malaria control methods to all at-risk Africans by the end of next year in hopes of eliminating all preventable malaria deaths by 2015" (Scott). Ray Chambers, the Secretary General's Special Envoy for Malaria, says, "This is a massive undertaking unlike anything that has ever been done before."

Sources:
Associated Press. (via VOAnews.com) [Photo]

Henry J. Kaiser Family Foundation. "African Leaders Malaria Alliance Launched At U.N. General Assembly." Medical News Today. 29 Sept 2009.

Nyaria, Sandra. "African Leaders in Alliance to End Malaria Deaths on Continent By 2015." VOAnews.com. 23 Sept 2009.

Stearns, Scott. "African Leaders Fight Malaria." VOAnews.com. http://www.voanews.com/english/2009-09-22-voa52.cfm?rss=topstories. 29 Sept 2009.

Infectious Bite needs your help

I'm pleased to tell you that recently Infectious Bite has received many emails from individuals who wish to help spread awareness about malaria. To those individuals: I sincerely thank you.
Infectious Bite is an awareness and education organization. You can show your support and deliver pertinent information about malaria to the public by adding one of these notes to your profile page or website. [Single click to view image. Right click, & save.]

A single dose of malaria medication costs approximately 13 cents. Unfortunately, infected individuals can often not afford or find the necessary medication. $10 buys and delivers a bed net (through MalariaNoMore, NothingButNets, or the CDC Foundation), which can protect two children nightly, and prevent them from contracting malaria.		There are 350-500 Million cases of malaria annually. Each year, there are about 1 Million deaths. Most of the dead are children and pregnant women.
Show your support and encourage action with this simple note.		It is estimated that Africa's annual GDP would increase by $100 Billion if malaria were eradicated. Malaria is not just a health problem, it is also an economic drain.

Malaria kills 350-500 million people each year. Per day, there are 2700 malaria-related deaths. This is a global health concern of massive proportions.
Malaria is a disease that infects all areas of life. The economies of malaria-laden countries suffers from a reduced or disabled workforce and high mortality rate. It is estimated that Africa's GDP would be $100 Billion dollars greater (annually) if malaria were eradicated.

You can also spread awareness about the devastation of malaria by purchasing and wearing an Infectious Bite t-shirt. Profits support our educational events and go to malaria relief.


We appreciate all offers for help. With your help we can bite malaria back.

Tigecycline treats malaria

"Increasing resistance of Plasmodium falciparum to existing drugs has resulted in the search for new antimalarial therapies" (American). "A new study suggests that tigecycline, the first member of a new class of antibiotics, shows significant antimalarial activity on its own and may also be effective against multi drug-resistant malaria when administered in combination with traditional antimalarial drugs" (ScienceDaily).

"Tigecycline is a novel glycylcycline antibiotic with a broad antibacterial spectrum" (Starzengruber). This drug was "specifically designed to overcome" drug-resistant disease (American). Research showed that it was "up to 6 times more active against P. falciparum than doxycycline," a medication that is commonly used to treat malaria (ScienceDaily). "Tigecycline shows no activity correlation with traditional antimalarials and has substantial antimalarial activity on its own" (Starzengruber). Researchers hope that because of "its clinical efficacy", Tigecycline may be used "in combination with faster-acting antimalarials in the...treatment of multidrug-resistant P. falciparum malaria in seriously ill patients" (American).

There are some side-effects to Tigecycline treatment, and the manufacturers warn that it "may cause fetal harm when administered to a pregnant woman" (Wyeth). Pregnant women are particularly susceptible to malaria. Every year, approximately one million people die from malaria, and most of them are pregnant women and children. Nevertheless, the reduction in number of malaria cases in a region will improve the general health and economy of that are and help reduce the likelihood that pregnant women will contract malaria.

Sources:
American Society for Microbiology. "New Antibiotic Shows Promise in Fighting Malaria." 17 Sept 2009.

ScienceDaily. "New Antibiotic Shows Promise In Fighting Malaria." 11 September 2009. 17 September 2009 .

Starzengruber, P. et al. "Antimalarial Activity of Tigecycline, a Novel Glycylcycline Antibiotic." 6 March 2009.

Wyeth.com. Tygacil. http://www.wyeth.com/hcp/tygacil. [Photo]

Monkey malaria

"Researchers in Malaysia have identified...an emerging new form of malaria infection" that is a "potentially deadly" strain of the disease (ScienceDaily). "Malaria kills more than a million people each year. It is caused by malaria parasites, which are injected into the bloodstream by infected mosquitoes" (Daneshvar).

"Recently, researchers at the University Malaysia Sarawak...showed that P. knowlesi, a malaria parasite previously thought to mainly infect only monkeys - in particular long-tailed and pig-tailed macaques found in the rainforests of Southeast Asia - was widespread amongst humans in Malaysia." After several similar reports, P. knowlesi has been deemed "the fifth cause of malaria in humans" (ScienceDaily).

P. knowlesi malaria is particularly dangerous because it "can easily be confused with P. malariae", a more benign form of malaria (ScienceDaily). Under the microscope, the two strains appear nearly identical, but the strains are very different in severity and deadliness. "One of the most significant findings of the study is that Plasmodium knowlesi was found to have the ability to reproduce every 24 hours in the blood -- meaning infection was potentially deadly. This, according to the researchers, meant early diagnosis and treatment were crucial" (Kounteya).

A universally low platelet count is another curious characteristic of this strain of parasite. "In other human forms of malaria, this would only be expected in less than eight out of ten cases." But, "all of the P. knowlesi patients - including those with uncomplicated malaria - had a low blood platelet count...The researchers believe the low blood platelet count could be used as a potential feature for diagnosis of P. knowlesi infections." (ScienceDaily).

"Recently, there have been cases of European travellers to Malaysia and an American traveller to the Philippines being admitted into hospital with knowlesi malaria following their return home" (ScienceDaily). This deadly strain of malaria may potentially spread across the globe and infect millions if it is not adequately treated and controlled.

Sources:
Daneshvar C, et al. Clinical and laboratory features of human Plasmodium knowlesi infections. Clin Infect Dis. 2009;49(6):852-60.

Kounteya Sinha. The Times of India. "Monkey malaria spreads to humans in South-east Asia". 11 September 2009.

ScienceDaily. In Humans. Retrieved September 13, 2009, from http://www.sciencedaily.com­ /releases/2009/09/090909103004.htm

Schweinsaffe im Tierpark Berlin (photo)