World Malaria Day: April 25, 2011

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National Institutes of Health (NIH) statement on World Malaria Day, by B.F. (Lee) Hall, M.D., Ph.D., and Anthony S. Fauci, M.D., National Institute of Allergy and Infectious Diseases, National Institutes of Health

In commemorating World Malaria Day and reflecting on this year’s theme, “Achieving Progress and Impact,” we celebrate the important strides made in many regions of the world to control malaria, while acknowledging the enormous challenges that remain.

In 2000, an estimated 350 million to 500 million clinical cases of malaria occurred worldwide and more than 1 million people died from the disease, according to the World Health Organization (WHO). By 2009, there were about 225 million cases of clinical malaria and 781,000 deaths.

Decreases in cases of malaria occurred in all affected regions, with the greatest decline in the number of malaria deaths occurring in Africa. Furthermore, in 2010, WHO certified that two countries, Morocco and Turkmenistan, had eliminated malaria — that is, reduced the incidence of infections in their countries to zero. Although these numbers reflect significant improvements, the global burden of malaria remains far too high and will require sustained and coordinated efforts from the international community to reduce it further.

Today we enter the third year of the Global Malaria Action Plan (GMAP) http://www.rbm.who.int/gmap/gmap.pdf, developed by the Roll Back Malaria (RBM) Partnership, http://www.rollbackmalaria.org/. The GMAP, an international framework for coordinated action against malaria, sets ambitious goals to control, eliminate and eradicate malaria.

The National Institutes of Health is committed to supporting the GMAP. To make continued progress and achieve long-term GMAP goals, we must build a sustainable pipeline of new products, novel interventions and innovative strategies to diagnose, treat and prevent malaria as well as interrupt its transmission. Below we describe examples of significant advances made in these areas during the past year.

The emergence and spread of parasites resistant to conventional anti-malarial drugs threatens treatment efforts. Recently, NIH grantees identified a novel compound  that rids mice of malaria-causing parasites with a single oral dose. This compound acts on a novel target in the parasite that may allow it to kill parasites that have developed resistance to other antimalarial drugs. Further studies will determine whether this compound can become a new therapy. Similarly, insecticide resistance can undercut mosquito-control strategies for containing malaria. Although research on insecticides with novel mechanisms of action continues, such compounds, like current insecticides, run the risk of selecting for the emergence and spread of mosquitoes resistant to the new insecticide. Therefore, novel approaches must be pursued.

NIH-funded researchers recently identified a genetically modified fungus  that blocks development of malaria parasites in the mosquito and thereby interrupts malaria transmission. Because the fungi do not kill the mosquitoes, they would be unlikely to develop resistance. Such fungi could become an important malaria intervention if future studies demonstrate that they are safe and effective.

Within the next few months, we expect to learn the results of a large-scale clinical trial in Africa of a candidate malaria vaccine known as RTS,S. We all hope that an effective vaccine that confers protection against the most deadly type of disease, Plasmodium falciparum malaria, soon will be available. Meanwhile, efforts to develop new and improved malaria vaccines continue globally, with 16 candidates currently in preclinical development and another 23 in clinical trials.

Early this year, we joined with others in announcing a renewed interest in the possible eradication of malaria, as described in the Malaria Eradication Research Agenda (MalERA), the result of a global consultation effort among multiple stakeholders and disciplines. A key message of MalERA is that the tools to eradicate malaria do not exist and must be developed. A major challenge will be to continually assess the changing epidemiology of malaria as control and elimination efforts prove successful to ensure that appropriate tools and interventions are developed and effectively deployed.

To bridge clinical and field research with new laboratory-based methods in immunology, molecular biology and genomics, we at the NIH National Institute of Allergy and Infectious Diseases recently launched a network of International Centers of Excellence for Malaria Research. This network, which supports teams of scientists conducting research in more than 20 malaria-endemic countries, will provide new insights from research conducted in the context of rapidly changing malaria epidemiology.

A strong foundation of scientific insight, technological innovation and effective implementation has enabled us to achieve progress and advance several fronts in the fight against malaria. We must sustain this critical foundation as we continue to work together toward our shared goals of global malaria control, elimination and eradication.

Source: NIH

Chemotherapy Drugs Show Promise in Fighting Malaria

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Ahead of World Malaria Day (25 April), EU-funded researchers have discovered that drugs originally designed to inhibit the growth of cancer cells can also kill the parasite that causes malaria. They believe this discovery could open up a new strategy for combating this deadly disease, which, according to World Health Organization statistics, infected around 225 million and killed nearly 800 000 people worldwide in 2009.

Efforts to find a treatment have so far been hampered by the parasite’s ability to quickly develop drug resistance. The research involved four projects funded by the EU (ANTIMAL, BIOMALPAR, MALSIG and EVIMALAR) and was led by laboratories in the UK, France and Switzerland with partners from Belgium, Germany, Denmark, Greece, Spain, Italy, Netherlands, Portugal, and Sweden, along with many developing nations severely affected by malaria.

“This discovery could lead to an effective anti-malaria treatment that would save millions of lives and transform countless others. This demonstrates yet again the added value both of EU-funded research and innovation in general and of collaboration with researchers in developing countries in particular. The ultimate goal is the complete eradication of the global scourge of malaria and collaborative work across many borders is the only way of confronting such global challenges effectively,” said Research, Innovation and Science Commissioner Máire Geoghegan-Quinn.

Cancer drugs to kill malaria parasite

Malaria is caused by a parasite called Plasmodium, which is transmitted via the bites of infected mosquitoes. In the human body, the parasites reproduce in the liver, and then infect and multiply in red blood cells. Joint research led by EU-funded laboratories at the Inserm-EPFL Joint Laboratory, Lausanne, (Switzerland/France), Wellcome Trust Centre for Molecular parasitology, University of Glasgow (Scotland), and Bern University (Switzerland) showed that, in order to proliferate, the malaria parasite depends upon a signalling pathway present in the host’s liver cells and in red blood cells. They demonstrated that the parasite hijacks the kinases (enzymes) that are active in human cells, to serve its own purposes. When the research team used cancer chemotherapy drugs called kinase inhibitors to treat red blood cells infected with malaria , the parasite was stopped in its tracks.

Until now the malaria parasite has managed to avoid control by rapidly developing drug resistance through mutations and hiding from the immune system inside liver and red blood cells in the body of the host, where it proliferates. The discovery that the parasite needs to hijack some enzymes from the cell it lives in opens up a whole new strategy for fighting the disease. Instead of targeting the parasite itself, the idea is to make the host cell environment useless to it, by blocking the kinases in the cell. This strategy deprives the parasite of a major modus operandi for development of drug resistance.

Several kinase-inhibiting chemotherapy drugs are already used clinically in cancer therapy, and many more have already passed phase-I and phase II clinical trials. Even though these drugs have toxic side-effects, they are still being used over extended periods for cancer treatment. In the case of malaria, which would require a shorter treatment period, the problem of toxicity would be less acute. Researchers are proposing therefore that these drugs should be evaluated immediately for anti-malarial properties, drastically reducing the time and cost required to put this new malaria-fighting strategy into practice.

The next steps will include mobilising public and industrial partners to verify the efficacy of kinase inhibitors in malaria patients and to adjust the dose through clinical trials, before the new treatments can be authorised and made available to malaria patients worldwide.

Background

Since 2002, the EU has invested nearly EUR 180 million in malaria research through the EU’s Framework Programmes for Research (FP6, 2002-2006, and FP7, 2007-2013).

The EU also contributes to the European and Developing Countries Clinical Trials Partnership (EDCTP) which aims to accelerate the development of new or improved drugs, vaccines and microbicides against HIV/AIDS, malaria and tuberculosis. Established in 2003, this successful ongoing European and African collaboration focuses on clinical trials as well as capacity building in sub-Saharan Africa. To date, 10 clinical trials on malaria costing EUR 69 million have been financed under EDCTP with EUR 35 million support from the EU.

Source: Europa.eu

Médecins Sans Frontières Calls for Switch from Quinine to Artesunate

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After the revision of World Health Organization (WHO) guidelines yesterday,  international medical humanitarian organization Médecins Sans Frontières (Doctors Without Borders) calls for a drug proven to reduce deaths in children suffering from severe malaria to be immediately rolled out in African countries.

In its new report, entitled “Making the Switch,” Médecins Sans Frontières (MSF) calls on African governments to follow new World Health Organization (WHO) guidelines, and switch from the far less effective quinine to artesunate, which could avert nearly 200,000 deaths each year. MSF also calls on WHO and donors to support governments so this urgent treatment change can happen quickly.

“When children arrive at the clinic with severe malaria, they often are having convulsions, vomiting or at risk of going into shock, and you just want to be able to give them effective treatment quickly,” said Veronique De Clerck, Medical Coordinator for MSF in Uganda. “For decades, quinine has been used in severe malaria, but it can be both difficult to use and dangerous, so it’s time to bid it farewell.  With artesunate, we now have a drug that saves more lives from severe malaria, and is safer, easier and more effective than quinine.”

Quinine has to be given three times a day in a slow intravenous drip that takes four hours, a treatment that is burdensome for both patients and health staff. Artesunate, in contrast, can be given in just four minutes, by giving a patient an intravenous or intramuscular injection.

A landmark clinical trial in late 2010 concluded that the use of artesunate to treat children with severe malaria reduces the risk of death by nearly a quarter.  The study, carried out in nine African countries, found that for every 41 children given artesunate over quinine, one extra life was saved.  Because of the complexities of administering quinine, children in the trial who were assigned to receive quinine were almost four times more likely to die before even receiving treatment.

MSF participated in the trial through its research affiliate Epicentre, with a research site in Uganda. MSF has since changed its own treatment protocols and now plans to work with national health authorities to roll out artesunate in its projects over the coming months.

The evidence is overwhelming, but MSF’s report stresses that change will not happen on its own. While WHO has now issued new guidelines recommending artesunate for treating severe malaria in children in Africa, it needs to also develop a plan to help countries make this switch.  African governments must urgently change their treatment protocols and donors must send a clear signal to countries that they will support the additional cost where needed.  Artesunate is three times more expensive, but the difference in cost of US$31 million each year for a global switch is very little for the nearly 200,000 lives that researchers say could be saved.

“We’ve been here before—when WHO changed its treatment recommendations for simple malaria in 2001 it took years for countries to actually make the switch, and shockingly, in some countries the far inferior drugs are still being used ten years on,” said Dr. Martin De Smet, who coordinates MSF’s malaria work.  “With severe malaria, WHO needs to make sure that the change is much less sluggish, so lives can be saved immediately.  There’s simply no excuse not to make the switch now.”

MSF provided malaria treatment to around one million people in 2010.  Severe malaria kills over 600,000 African children under the age of five annually.  Each year, around eight million simple malaria cases progress to severe malaria, where patients show clinical signs of organ damage, which may involve the brain, lungs, kidneys or blood vessels.

More information: Full MSF Report (PDF)

Source: MSF

“SMS for Life” Malaria Initiative for Tanzania Announced

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In commemoration of World Malaria Day 2011 (25 April), organizations in an innovative public-private initiative announce the nationwide roll-out of a unique malaria treatment access initiative, “SMS for Life,” across the United Republic of Tanzania. The roll-out follows a successful pilot project where mobile and electronic mapping technology was used to track the stock levels of anti-malarial drugs at health facilities to manage supplies of these essential treatments.

Launched in 2009, the “SMS for Life” pilot ran across three districts in Tanzania, ensuring access to essential malaria treatments for 888,000 people. 99% of health facilities involved avoided stock-outs of the artemisinin-based combination therapy (ACT), one of the main anti-malarial medicines.2 “SMS for Life” will now be deployed across 5,000 health facilities in 131 districts in Tanzania, covering a population of over 40 million.

Under the auspice of the Tanzanian Ministry of Health and Social Welfare, this roll-out is led by Novartis and supported by Vodacom, Medicines for Malaria Venture (MMV) and the Swiss Agency for Development and Cooperation, all under the umbrella of the global Roll Back Malaria Partnership.

Malaria kills about 800,000 people each year, the vast majority of whom live in sub-Saharan Africa where the disease is a leading cause of death for children under five, claiming the life of a child every 45 seconds.2 Although malaria is preventable and treatable, life-saving medicines do not always reach the patients who need them, particularly those living in remote areas. Stock-outs are a major hurdle in the maintenance of access to essential malaria treatments.

H.E. Dr Hadji Hussein Mponda, Minister for Health & Social Welfare in Tanzania, said “the simple truth is that if there are no effective malaria treatments available in the health facilities then people will likely die, especially young children and pregnant women who are most at risk of the disease. Reducing antimalarial drugs stock-outs saves lives, and so we are delighted that the SMS for Life programme that improves stock position information will now be rolled-out across Tanzania and we welcome this innovation.”

“SMS for Life” has demonstrated that we can overcome the longstanding problem of stock-outs at the health facility level. This flexible scheme can be implemented quickly and at relatively low cost in any country to track any medicine,” said Jim Barrington, “SMS for Life” Program Director and former Chief Information Officer at Novartis. “It’s rewarding to see how a unique partnership, which combines the specific skills and experience of its various members to deliver an innovative use of everyday technologies, positively impacts the lives of malaria patients, their families and communities. “SMS for Life” also has great potential to be implemented in all malaria endemic countries and within other disease areas.”

In addition to the roll-out in Tanzania this year, two further pilots will start. Kenya, with funding from Novartis via the global employee survey donation program, will implement a five district pilot to track ACTs and rapid diagnostic tests (RDTs), in addition to collecting weekly case management data. MMV, through partnership with University of Oxford, will provide technical support for the implementation and evaluation of the pilot project. Ghana, with funding from Swiss TPH, will implement a six district pilot to track malaria medicines, an antibiotic and RDTs. Accurately monitoring the amount of essential medication, such as ACTs and quinine injectables, available in a given location, reduces the risk of shortages and stock-outs and ensures that treatments are available to malaria patients, even in the most remote areas, where and when they are needed.

Each week, automated SMS messages are sent to staff at participating healthcare facilities, prompting them to check the stock of anti-malarial medicines, and reply with an SMS detailing current stock levels. These messages are collected in a central web-based system that provides the District Medical Officers and other users with real-time stock level information, accessible via the Internet or their mobile phone. Using this information, District Medical Officers are able to redistribute essential medicines to where they are most needed and coordinate emergency deliveries to health facilities if necessary.

The Global Business Coalition on HIV/AIDS, Tuberculosis and Malaria (GBC) Business Action on Health Awards Review Committee has recently selected the “SMS for Life” program as a Finalist for the Technology for Health award.

About “SMS for Life”
“SMS for Life” is an innovative public-private partnership that harnesses everyday technology to improve access to essential malaria medicines in rural areas. It uses a combination of mobile phones, SMS messages and electronic mapping technology to track weekly stock levels at public health facilities in order to eliminate stock-outs, increase access to essential medicine and reduce the number of deaths from malaria.

“SMS for Life” was initially piloted across three districts in the United Republic of Tanzania, covering 129 health facilities and 226 villages, representing 1.2 million people. When launched in 2009, 26% of all health facilities did not have any ACTs in stock, but by the end, 99% had at least one ACT dosage form in stock. In addition, 888,000 people in the three pilot districts had access to all malaria treatments at the close of the pilot, versus 264,000 people at the start, which helped to reduce the number of deaths from malaria.

About the partners
Under the Tanzanian Ministry of Health and Social Welfare and the National Malaria Control Programme (NMCP) is the Directorate of Preventive Services. NMCP is the custodian of all malaria prevention and control activities in the country. The NMCP is the owner and main user of the ‘SMS for Life’ solution and coordinates all project activities in the country, including planning, implementation & evaluation of the project. The NMCP also makes sure that all the districts selected are fully engaged in the process.

Novartis drives the overall initiative and has taken the lead in defining the solution, sourcing the partners, establishing a steering committee, liaising with the Ministry of Health in Tanzania and RBM Partnership Secretariat and providing all the resources and funding necessary to complete the pilot in Tanzania.

Medicine for Malaria Venture (MMV) is, along with SDC, one of two funders of the country implementation of the solution. They also manage funds from SDC, giving them the role of managing all project funding. In addition, MMV is coordinating the national training program and is contracting technology deployment required to affect this rollout.

The Swiss Agency for Development (SDC) is the second and major funder of the Tanzanian nationwide roll-out. Its grant is managed by MMV.

Vodacom, a local Tanzanian Mobile operator is providing, in addition to promotional materials like tshirts, smart phones with Internet and data access for use by all District Medical Officers and Malaria Focal persons.

Vodafone supported the design, development and the implementation of the technical solution for the Tanzanian Pilot in 155 health facilities until its completion in February 2010.

IBM supported the overall management of the pilot project and the provision of an on-line collaboration tool, “Lotus Live”. The tool allowed all the project partners to coordinate their inputs.

RBM Partnership Secretariat facilitates oversight, including the work of the steering committee and leads advocacy activities. It helps provide ongoing guidance throughout the project, placing it in the broader context of RBM’s activities.

About RBM
The Roll Back Malaria (RBM) Partnership is the global framework for coordinated action against malaria. It provides a neutral platform for consensus-building and developing solutions to challenges in the implementation of malaria control interventions and strategies. RBM is a public-private partnership that also facilitates the incubation of new ideas and lends support to innovative approaches.

The Partnership promotes high-level political commitment and keeps malaria high on the global agenda by enabling, harmonizing and amplifying partner-driven advocacy initiatives. Founded by UNICEF, WHO, the World Bank and UNDP and strengthened by the expertise, resources and commitment of more than 500 partner organizations, the Partnership secures policy guidance and financial and technical support for control efforts in countries and monitors progress towards universal goals.

Source: World Health Organization (WHO), Roll Back Malaria

The Global Fund to Fight AIDS, Tuberculosis and Malaria Welcomes Passage of 2011 U.S. Budget

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The Global Fund to Fight AIDS, Tuberculosis and Malaria has welcomed passage of the continuing resolution for the Fiscal Year 2011 U.S. budget which contains a US$1.05 billion contribution to The Global Fund.

“I offer my sincere thanks to the U.S. on behalf of the millions of people around the world who benefit from resources channeled through The Global Fund. I am grateful to President Obama and the U.S. Congress for this vote of confidence in the Global Fund and for standing firm by U.S. commitments to global health despite significant pressure to reduce budget deficits,” said Professor Michel Kazatchkine, Executive Director of The Global Fund. “Tens of thousands of lives will be saved as a direct result of this budget. And I hope that it will inspire other countries to follow the lead of the United States.”

With total commitments of more than US$ 22 billion to grants in 145 countries, The Global Fund provides two thirds of all international funding to fight TB and malaria and supports programs providing AIDS treatment to more than half of all the people who need it in the developing world. The United States contributions make up nearly one third of the total commitments to the Global Fund.

During testimony before the House Appropriations Subcommittee on State, Foreign Operations and Related Programs last Thursday just hours before the vote in the House and the Senate, Dr. Christoph Benn, the Global Fund’s Director of External Relations and Partnerships, thanked the Obama Administration and Congress for their continued support leading to a bipartisan effort to protect international health funding despite the significant budgetary pressures.

“The Global Fund fully understands that these are difficult economic times and that hard choices have to be made,” Dr Benn told the committee. “However, the resources allocated to the Global Fund, as well as the U.S. bilateral programs PEPFAR and PMI, represent excellent value for money.” Dr. Benn made clear that with continued U.S. leadership, The Global Fund can leverage U.S. funding so we can “turn the corner on the three diseases and increase stability, growth and security around the globe.”

Source: The Global Fund to Fight AIDS, Tuberculosis and Malaria

The Institute for OneWorld Health Announces Development of Alternative Source of Artemisinin

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The Institute for OneWorld Health (iOWH), a non-profit drug development organization, announced today that its development of an alternative source of artemisinin using pioneering synthetic biology technology (semisynthetic artemisinin (ART) project) has successfully entered the production and distribution phase.

The semisynthetic version of artemisinin is targeted to be an affordable, non-seasonal and complementary source of ART and will stabilize price volatility and alleviate shortages – key factors in meeting future demand in developing nations and around the globe.

iOWH, in collaboration with its strategic partners, successfully completed the scientific work necessary to enter the production and distribution phase of the project. Through a unique public-private partnership with sanofi-aventis, a leading global pharmaceutical company, this phase will enable production of semisynthetic ART. Sanofi has made essential contributions during the project’s development and industrialization phase, and is going to manufacture and distribute the semi synthetic artemisinin version to any qualified buyer. The substantial investment sanofi-aventis is making in this project will make it possible to facilitate integration of semisynthetic ART into the ACTs and the global supply chain, with an estimated goal to begin distribution in 2012.

“When we started work on this project, nearly six years ago, we knew that this would be a major challenge from technical, scientific, and humanitarian standpoints. Here we are today; however, ready to begin the production and distribution phase in collaboration with sanofi, thanks to the hard work of our team, our collaborators, and our subgrantees, as well as generous support from our funders. Our goal is that one day; no child will die from malaria. Providing an alternative source of artemisinin is a breakthrough in the fight against malaria,” said Richard Chin, M.D., CEO of iOWH.

“Realizing this project brings us enormous satisfaction that only our profession, devoted to public health and patient care, can offer. Contributing to a project which saves lives and relieves suffering within the context of a fair trade economic model, combined with technological challenges and partnership, is a source of inspiration for all members of our team,” said Francis Carré, CEO of Sanofi Chimie.

iOWH has led this project, funded by the Bill & Melinda Gates Foundation, in collaboration with Amyris Inc. and sanofi-aventis. The synthetic biology technology is based on pioneering inventions licensed from the University of California at Berkeley and the University of Saskatchewan. Headquartered in South San Francisco, iOWH is a non-profit that discovers, develops and delivers safe, effective and affordable new medicines for vulnerable population with infectious diseases in the developing world, with emphasis on diseases that disproportionately affect children.

Source: Business Wire

“Imagine No Malaria” Campaign Uses Text Messaging and Social Networking to Raise Funds to Fight Malaria

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The United Methodist Church (UMC) in Nashville, Tennessee  (USA) has launched an extensive campaign called “Imagine No Malaria.” The campaign leverages traditional advertising, as well as mobile phones and social networking. Using SMS text messaging, individuals can donate money, and UMC also encourages people to organize “house parties” to raise money for the cause. The organization’s goal is to raise $100 million to help eradicate malaria by 2015. To date, t $17.5 million has been raised, according to the New York Times.

via New York Times.

Malaria – Pipeline Review, Q1 2011 – Market Research Reports

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Global Markets Direct’s, “Malaria – Pipeline Review, Q1 2011,” provides an overview of the Malaria therapeutic pipeline.

This report provides information on the therapeutic development for Malaria, complete with latest updates, and special features on late-stage and discontinued projects. It also reviews key players involved in the therapeutic development for Malaria. “Malaria – Pipeline Review, Q1 2011” is built using data and information sourced from Global Markets Direct’s proprietary databases, Company/University websites, SEC filings, investor presentations and featured press releases from company/university sites and industry-specific third party sources, put together by Global Markets Direct’s team.

via Malaria – Pipeline Review, Q1 2011 – Market Research Reports.

Letting Mosquitos Breed May Help Fight Malaria

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It may seem counter-intuitive at first but letting mosquitoes grow up and breed may be part of the solution to tackling the devastating impact of malaria.

A team of researchers led by Dr Stephen Gourley of the University of Surrey’s Mathematics Department have used mathematical modeling to examine why conventional insecticides used against the insects that transmit the disease responsible for millions of deaths a year, can quickly become ineffective in areas of intensive use. Their answers may lead to unprecedented advances in malaria control.

Mosquitoes can become resistant to commonly used insecticides surprisingly rapidly and spraying them while young simply imposes intense selection pressure favoring resistant insects.

Biologists have suggested that a new kind of late-acting insecticide could slow this process and lead to insecticides which would remain effective over a much longer period of time. The strategy aims to exploit the fact that mosquitoes only become able to infect humans with malaria late in their lifetime, due to a relatively long latency stage. This means that the delayed action insecticide doesn’t result in increased infection rates while the younger insects remain alive.

It could, however, mean a rise in the number of troublesome, but non-malarial, mosquitoes.

Dr Gourley said: “There is a trade-off between effective prevention of malaria transmission by mosquitoes and having to live with mosquito bites involving no malarial transmission.”

In 2008 malaria caused almost one million deaths and remains one of the leading causes of child mortality in Africa. More of the insects in general, but fewer with the deadly disease, may be a price worth paying.

Conventional insecticides, such as DDT, kill mosquitoes as soon as they are exposed to the chemical. But while this approach works well in the short term, its indiscriminate action speeds up the evolution of the insect towards insecticide resistance.

In particular, because the insecticide acts on female mosquitoes before they lay eggs, this causes intense selection pressure towards insecticide-resistant females who then pass on this resistance to their offspring.

Dr Gourley’s team used mathematical models to predict the effect of an insecticide that only acts after a time delay, once the mosquitoes have laid their eggs. Because this results in a much lessened selection pressure on resistant mosquitoes, the team discovered that resistance evolves much more slowly with this type of insecticide.

The technique could result in vastly improved malaria control in areas where resistance to current insecticides is rife amongst mosquitoes.

The academic paper on the subject is authored by Stephen A. Gourley, Rongsong Liu and Jianhong Wu. It is titled “Slowing the evolution of insecticide resistance in mosquitoes: a mathematical model” and was published in the Proceedings of the Royal Society, Series A.

Source: University of Surrey – Guildford

Monkeys Provide Malaria Reservoir for Human Disease in South-East Asia

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Macaque Monkey

Juvenile Macaque - Sandakan, Malaysia. Photo by Frances Williams (Sandakan-Travel.com).

Monkeys infected with an emerging malaria strain are providing a reservoir for human disease in Southeast Asia, according to recent research. The study confirms that the species has not yet adapted to humans and that monkeys are the main source of infection.

Malaria is a potentially deadly disease that kills over a million people each year. The disease is caused by malaria parasites, which are transmitted by infected mosquitoes and injected into the bloodstream.

There are five species of malaria parasite that are known to cause disease in humans, of which Plasmodium knowlesi is the most recently identified. Previously thought to only infect monkeys, researchers have shown that human P. knowlesi infections are widely distributed in Southeast Asia and that it is a significant cause of malaria in Malaysian Borneo. Until now, it was not clear whether the infection is transmitted from person to person, or is passed over from infected monkeys.

Researchers led by Professor Balbir Singh at the Malaria Research Centre, Universiti Malaysia Sarawak, collaborating with Sarawak State Health Department, St George’s University of London and the London School of Hygiene and Tropical Medicine, examined blood samples from 108 wild macaques from different locations around the Sarawak division in Malaysian Borneo. Their results reveal that 78% were infected with the P. knowlesi species of malaria parasite, and many were infected with one or more of four other species of monkey malaria parasites that have not yet been found in humans.

By comparing the molecular identity of the parasites from monkeys and those isolated from patients with knowlesi malaria, the team were able to build a picture of the evolutionary history of the parasite and its preferred host. Their analysis reveals that transmission of the knowlesi species is more common amongst wild monkeys, than from monkeys to humans, and that monkeys remain the dominant host.

“Our findings strongly indicate that P. knowlesi is a zoonosis in this area, that is to say it is passed by mosquitoes from infected monkeys to humans, with monkeys acting as a reservoir host,” explains Professor Singh. “However, with deforestation threatening the monkeys’ habitat and increases in the human population, it’s easy to see how this species of malaria could switch to humans as the preferred host. This would also hamper current efforts aimed at eliminating malaria.”

Based on the molecular data, the researchers estimate that the knowlesi malaria species evolved from its ancestral species between 98 000 and 478 000 years ago. This predates human settlement in the area, meaning that monkeys are mostly likely to have been the initial host for the parasite when the species first emerged. This estimate also indicates that the species is as old as, or older than, the two most common human malaria parasites, P. falciparum and P. vivax.

The study was funded by the Wellcome Trust, a global charitable foundation that supports biomedical research and the medical humanities. It was published today in the journal PLoS Pathogens.

Source: The Wellcome Trust