NIH researchers develop two new malaria tests

Two new tests to detect drug-resistant malaria have been developed by researchers from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), working with French and Cambodian colleagues in Cambodia. Both tests can discern within three days whether the malaria parasites in a given patient will be resistant or susceptible to artemisinin, the key drug used to treat malaria.

Current drug-responsiveness tests can be expensive and slow as they require malaria patients to be hospitalized for blood draws every six hours during the course of several days.

The new study was led by Rick Fairhurst, M.D., Ph.D., of the NIAID Laboratory of Malaria and Vector Research, and Didier Menard, Ph.D., of the Institut Pasteur du Cambodge, Cambodia. The first test developed is conducted on blood taken from a malaria patient at the same time as the first dose of artemisinin-based combination drug therapy is administered. The test returns results in 72 hours and can predict whether the patient has slow-clearing, drug-resistant parasites. The researchers note that the simple, new test could be used for surveillance studies to monitor and map the emergence or spread of artemisinin-resistant malaria parasites.

The second test is conducted on parasites grown in the laboratory. This test requires trained technicians to adapt parasites from a malaria patient to a laboratory culture, synchronize the life-stages of the parasites, and then apply the drug only to those that are three hours old or younger. According to the NIH, this test will likely be most useful in future studies designed to elucidate the molecular basis of artemisinin resistance and to screen new malaria drugs.

The studies were published recently in The Lancet Infectious Diseases journal.

According to the World Health Organization (WHO), there were around 219 million cases of malaria worldwide in 2010 and an estimated 660,000 deaths from the disease.