case study
The well-studied risk factors for VL are: • Poverty. • Living in a mud/thatched house. • Current or recent VL patients living in the household or around. • Poor environmental conditions and sanitation. • Poor knowledge about VL and its vector control. • Low use of bednets. Favorable factors for controlling the disease in the Indian sub-continent are: • Humans are the only reservoir of the parasite. • The sand fly P. argentipes is the only vector of the disease. • The disease can be diagnosed at the household level among suspected VL patients. • Oral medicine “Miltefosine” can cure the disease with a success rate of 90% and above. • Availability of other effective drugs such as Liposomal Amphotericin B, Paromomycin, and Amphotericin Deoxycholate.
Integrated vector control management One of the main pillars of national VL elimination strategies is to control sand flies to interrupt transmission of visceral leishmaniasis. The Regional Technical Advisory Group for elimination of visceral leishmaniasis in the Indian sub-continent suggested integrated vector control management (IVM) as the main tool to control the sand fly vector of VL. IVM includes indoor residual spraying with insecticides (IRS), use of insecticide-treated materials (ITM), environmental management, and social mobilization for vector control.
Unfortunately, experiences with IRS using DDT in India is frustrating due to emerging sand fly resistance to DDT, and complete lack of funding, logistics, and human resources for vector control in Bangladesh and to some extent in Nepal. All these make IRS a hard to Miltefosine resistant VL cases can reach vector control tool in these be treated with Liposomal countries. Furthermore, an operation Amphotericin B at an affordable like IRS is expensive, labor-intensive, cost thanks to WHO special and requires sustainable infrastructures, arrangements for VL cases in the supplies of insecticide, spraying Indian sub-continent. The unique equipment, trained personnel, and epidemiological features, easy funding over a long-term period. These diagnosis, and availability of create doubts about the sustainability effective treatment created hope for of IRS in poor resource settings like eliminating the disease from the The author: Bangladesh. Moreover, resurgence of Indian sub-continent if an adequate DINESH MONDAL VL in the Indian sub-continent after and sustainable vector control ICDDR,B ceasing IRS with DDT in the early method could be discovered and Bangladesh 1990s, and recently demonstrated implemented properly. lower acceptance of IRS in India In 2005 the Governments of Bangladesh, India indicate that IRS may not be a sustainable vector and Nepal signed a Memorandum of Understand control method. Thus as an alternative to IRS, ing, and committed to eliminating visceral other effective vector control tools with high leishmaniasis from this sub-continent. The acceptance by the community are highly desired. elimination target is to reduce the incidence of VL to less than 1 per 10,000 people by 2015 at the Seeking a sustainable vector control tool district level in India and Nepal, and sub-district A sustainable vector control tool for controlling (upazila) level in Bangladesh. vector-borne diseases like VL has to be highly effective in reducing vector density, which will lead to reduced transmission of the disease. It 32
PUBLIC HEALTH JOURNAL 23/2012