A woman takes medication as part of an attempt to control the spread of filariasis

WHO/TDR/Crump

Research in Ghana has shown that a single course of a cheap antibiotic can prevent and relieve symptoms of the disfiguring tropical disease lymphatic filariasis.

The disease, also known as elephantiasis, is caused by parasitic worms that are spread from person to person by mosquitoes.

Current treatments kill the worm larvae but have only a limited effect on adult worms, meaning they prevent the disease from spreading but do not cure the symptoms of those who already carry the parasite.

The worms infect about 120 million people in developing countries. In about four per cent of cases, the parasite makes patients' legs — and, in men, their scrotum — swell up greatly. This often renders patients unable to work.

The recent study was carried out in a region of Ghana where the disease is common. Fifty-one patients were given either a placebo or a six-week course of the antibiotic doxycycline, with the aim of targeting bacteria that live inside the worms.

In patients who received the drug, the adult worms were almost completely eradicated. In addition, those with swelling said it had been reduced.

Lead researcher Achim Hoerauf of the University of Bonn in Germany says there could be two explanations for this last result: the antibiotic may kill the bacteria that live inside the worms, and which are vital to them, or it may kill other bacteria that infect people through skin lesions on their swollen limbs.

Hoerauf told SciDev.Net that it might be possible to reverse the swelling entirely if it is detected and treated early enough, through surveillance programmes in schools, for example.

"The idea is to get more funding to pave the way for an integrated programme, alongside other vaccination efforts and education campaigns," he said.

According to Mark Taylor, another researcher on the study, doxycycline is readily and cheaply available to people with filariasis.