Visceral leishmaniasis: Research projects

Case finding/management

There are three specific areas of TDR research to help eliminate visceral leishmaniasis from India, Nepal and Bangladesh.

People living in remote areas who have visceral leishmaniasis can have no symptoms, and consequently remain in the community for weeks or months before seeking medical care from a qualified practitioner. As a result, they can die from an opportunistic co-infection, internal bleeding or severe anemia, and increase the potential for others to be infected. TDR is working with multiple partners to study new ways to reach into the community to find potential VL cases in India, Bangladesh and Nepal. A cost analysis of various strategies for kala azar case detection and treatment is also being done.

Vector control

There are three main projects investigating how to reduce the ability of the sandflies that transmit the disease to infect people.

1.Study of feasibility, cost and coverage of community-based VL vector control in Bangladesh through insecticide-treated bednets

Insecticide spraying on household walls to kill the sand flies that carry the parasite is expensive and dependent on sprayers; existing bednets in 98% of the households have been treated with slow release insecticides. This research is examining how the distribution and use of bednets can be managed and supervised by community volunteers and how much it reduces the sand fly densities.

2.Cost-effective integrated vector management (IVM) in Nepal

A pilot training of district health staff and vector control has shown that this education is beneficial. The long-term impact is now being evaluated.

3.Usefulness, feasibility and cost of vector control monitoring in kala azar-endemic districts of Bihar, India

A pilot monitoring and evaluation toolkit that was developed for vector control operations identified on-time delivery issues, which were then corrected. The effectiveness of this toolkit on a regular basis in normal, field conditions is now being studied.

Two publications have already come out of work with local researchers and national programme officers and are being integrated into the national VL elimination programs in India, Nepal and Bangladesh.

Therapy for VL

hese studies are looking at the effectiveness of two different drug treatments. The first regards liposomal amphotericin B (AmBisome). One study is determining the efficacy and safety of a dose of 3 mg/kg daily for 5 days. The second is looking at whether a single dose is feasible in primary health care centres, close to the endemic villages in Bihar, India and Bangladesh. If successful, the single intravenous drip that takes about 2 hours will be an important improvement over the current standard of miltefosine pills over a 28 day course. Many people do not finish this treatment because it requires such a long time period and there are toxic side effects.

The oral form of a different drug, miltefosine, is being assessed for its safety and efficacy in patients with PKDL, a complication of visceral leishmaniasis that causes a serious rash in a patient who has recovered and is otherwise well.