U.S. Funds Projects to Fight Vector-borne Diseases in South Asia

Malaria, Japanese encephalitis, kala-azar all targeted with new methods

Story by Erin Block, Washington File Writer

Washington -- Across South Asia, vector-borne diseases have caused mortality and disease rates to soar. For the past five years a regional health program has led to more effective diagnosis and treatment, prevention and control of environmentally linked diseases.

"We were able to come up with very specific recommendations for prevention and control, and new techniques for diagnosis and treatment," said Dr. Panduka Wijeyaratne, resident advisor for the Environmental Health Project in Nepal.

The Environmental Health Project, a $107 million global mission funded by U.S. Agency for International Development (USAID), worked on vector-borne diseases primarily in Bangladesh, Bhutan, India and Nepal and focused on three vector-borne diseases: malaria, Japanese encephalitis and kala-azar.

"These countries have had so much experience with these diseases. They are recurrent, draining a country's resources year after year," said Nihal Goonewardene, president of the International Science and Technology Institute, which works for USAID on the Environmental Health Project.

Wijeyaratne added that archaic medical practices, poverty and inaccessibility to health care have allowed vector-borne diseases to gain a strong grip on the region and move across national borders.

One of the project's initiatives involved cross-border plans for tackling the vector-borne diseases in a more comprehensive way.

"For lesser developed countries we have helped them to take advantage of their more developed neighbors," said Wijeyaratne. "Sharing methodology and information helps stop the spread of disease."

Malaria and Japanese encephalitis, carried by infected mosquitoes, cause approximately 50,000 deaths annually in South Asia. Malaria is a parasite infection of the blood and can lead to kidney failure, coma or death. Insecticide sprays have been used to fight malaria in the past, but this proved to be too costly for developing countries such as Nepal.

"We are training the community to administer preventative measures to their own land," said Wijeyaratne. "By treating the areas with locally made materials, such as lime, we have been able to cut down on cost and made prevention more accessible to people in rural areas."

Japanese encephalitis is a severe viral disease of the central nervous system that can cause paralysis and seizures, and if left untreated, death. There is a vaccine for Japanese encephalitis, but it has been difficult for developing countries to make the vaccine available to the public.

"They did not know how many cases existed in the country, and without knowing that information it is difficult to introduce a vaccination program," said Wijeyaratne. "We helped the country develop a database for how many people have the disease.

Another problematic disease, kala-azar, is a parasite transmitted by sand flies, and damages internal organs. The disease leads to liver and spleen enlargement and is fatal nearly 100 percent of the time if left untreated. Kala-azar affects 500,000 people annually, and approximately 90 percent of these cases occur in Bangladesh, India, Nepal and Sudan.

Previously, diagnosis for Kala-azar was very difficult, involving biopsy of the liver or spleen or puncture of the bone marrow or a lymph gland. But EHP has introduced a new diagnostic technique that requires only a finger-prick of blood.

Treatment programs have also changed from an injection drug to an oral medication. This has led to more people being treated and fewer people dying.

"People had been injected with drugs and it was very painful for them. They didn't like it, which meant people stopped having the treatment, which meant they died. The death rates have been significant," said Wijeyaratne.

The injection also proved too costly because patients had to be hospitalized. The oral drug will be less painful and more accessible to people out in very rural areas because the drug won't have to be administered in hospitals, said Wijeyaratne.

"Things have started to happen, and it's very possible that South Asia can control these diseases," said Wijeyaratne.