Accessibility links

Treatment to Fight Parasitic Disease Successful

Researchers have found that a new treatment being used around the world to fight a common parasitic disease is working well.

Lymphatic filariasis causes grotesque swelling of the arms and legs as well as the area around the testicles in men. It is a leading cause of disability in the Third World, affecting nearly 90 million people in 80 poor countries.

The disease is spread to humans through the bite of a mosquito infected with the filariasis parasite. As with all parasitic diseases, there's a vicious cycle between humans and mosquitos in the transmission of the parasite. Humans and mosquitos go back and forth in giving each other the disease-causing parasite.

Several years ago, researchers realized they might be able to break the cycle if they killed the female parasite with antibiotics so she could not reproduce offspring in either the mosquito or in humans. The therapy amounts to a single shot of antibiotics once a year for four to six years.

Jim Kazura of Case Western Reserve University in Cleveland, Ohio, was one of the people who led the research. It helped launch a global effort sponsored by the World Health Organization and fueled by private sector donations to eradicate filariasis.

Now, a study of antibiotic therapy in remote villages of Papua, New Guinea, by Dr. Kazura and his colleagues confirms the earlier research that antibiotic therapy to kill the adult female parasite is safe and highly effective.

"The remarkable finding was we were actually able to reduce the level of transmission by over 90 percent," Dr. Kazura said. "Even in areas of the world that has among the highest transmission levels of any place that can be found."

Another surprising finding, the grotesque swelling of the arms and legs, and swelling of the testicles, goes away with treatment. Doctors once thought the swelling was a permanent condition.

Eric Otteson, who is with the School of Public Health at Emory University in Atlanta, Georgia, says studies like Dr. Kazura's are an important test of the eradication program in places like Papua, which has among the highest rate of infection in the world.

"It was a particularly difficult challenge to the strategy," he said. "But after four years, things are working just the way they ought to work. So, we need that kind of research to make sure we're on the right track."

The study by Dr. Kazura and colleagues, and an accompanying editorial by Dr. Otteson, are published in the New England Journal of Medicine.