Parasites Show Signs of Resistance to Malaria Treatment

December 20, 2005 -- Some malaria parasites show signs of potential resistance to artemisinin derivatives, drugs derived from the sweet wormwood plant, Artemisia annua. Malaria treatments containing artemisinins typically cure 90 percent of patients within days, even in areas with parasites resistant to other drugs.

Malaria is responsible for more than a million deaths every year, according to the World Health Organization. Falciparum malaria, caused by the protozoan parasite Plasmodium falciparum, is the deadliest form of the disease in humans and the focus of most research on resistance to antimalarial drugs. Scientists recently analyzed P. falciparum from blood samples of patients in Cambodia, French Guiana, and Senegal to set up an early-warning system for signs of resistance. They found no molecular signs of resistance to an artemisinin derivative in samples from Cambodia, but they did find evidence of resistance in some samples from French Guiana and Senegal. In a study published in the British medical journal The Lancet, the scientists stressed the need for increased vigilance and a coordinated and rapid deployment of drug combinations to avert further development of resistance to artemisinin-derived drugs.

There are several National Academies reports on malaria control. The Institute of Medicine report Saving Lives, Buying Time: Economics of Malaria Drugs in an Age of Resistance offers recommendations on maximizing the effectiveness of antimalarial drugs, emphasizing the use of artemisinin-based combination therapies, and the creation of a global subsidy that would make these effective combination treatments affordable and widely available in nations heavily afflicted by the disease. Microbial Threats to Health: Emergence, Detection, and Response discusses the current state of knowledge and policy pertaining to emerging and re-emerging infectious diseases and urges the U.S. government play a significant role in building the capacity of poor countries to monitor, prevent, and respond to disease outbreaks. The National Research Council report Malaria Control During Mass Population Movements and Natural Disasters reviews recent scientific literature relevant to establishing malaria control programs in situations involving forced migration, conflict, and other emergencies.

• Saving Lives, Buying Time: Economics of Malaria Drugs in an Age of Resistance 2004
• Microbial Threats to Health: Emergence, Detection, and Response 2003
• Malaria Control During Mass Population Movements and Natural Disasters 2002

• World Health Organization Malaria Information Page