Options for Active Case Detection of Visceral Leishmaniasis in Endemic Districts of India, Nepal and Bangladesh, Comparing Yield, Feasibility and Costs

Abstract

BackgroundThe VL elimination strategy requires cost-effective tools for case detection and management. This intervention study tests the yield, feasibility and cost of 4 different active case detection (ACD) strategies (camp, index case, incentive and blanket approach) in VL endemic districts of India, Nepal and Bangladesh.Methodology/Principal FindingsFirst, VL screening (fever more than 14 days, splenomegaly, rK39 test) was performed in camps. This was followed by house to house screening (blanket approach). An analysis of secondary VL cases in the neighborhood of index cases was simulated (index case approach). A second screening round was repeated 4–6 months later. In another sub-district in India and Nepal, health workers received incentives for detecting new VL cases over a 4 month period (incentive approach). This was followed by house screening for undetected cases. A total of 28 new VL cases were identified by blanket approach in the 1st screening round, and used as ACD gold standard. Of these, the camp approach identified 22 (sensitivity 78.6%), index case approach identified 12 (sensitivity – 42.9%), and incentive approach identified 23 new VL cases out of 29 cases detected by the house screening (sensitivity – 79.3%). The effort required to detect a new VL case varied (blanket approach – 1092 households, incentive approach – 978 households; index case approach – 788 households had to be screened). The cost per new case detected varied (camp approach $21 – $661; index case approach $149 – $200; incentive based approach $50 – $543; blanket screening $112 – $629). The 2nd screening round yielded 20 new VL cases. Sixty and nine new PKDL cases were detected in the first and second round respectively.Conclusions/SignificanceACD in the VL elimination campaign has a high yield of new cases at programme costs which vary according to the screening method chosen. Countries need the right mix of approaches according to the epidemiological profile, affordability and organizational feasibility.

DDT-based indoor residual spraying suboptimal for visceral leishmaniasis elimination in India

“…In addition to issues with vector control, there may be a lack of diagnostic facilities at peripheral levels of the health system, resulting in delay in the treatment of VL and PKDL, which may act as human reservoirs. Drug stock-outs or drug quality may also be an issue in effective treatment (16).…”

“…Older models also predict that IRS is capable of achieving VL elimination, provided that sand fly densities are reduced by 67% (15). Given that effective prevention through vector control and rapid diagnosis and treatment methodologies exist (7,16), elimination of VL in this region should therefore be technically feasible. However, in order for the predicted outcomes of IRS to become a reality, the IRS itself must be of sufficient quality to achieve an impact (17,18).…”

Economic and Financial Evaluation of Neglected Tropical Diseases

“…Four studies evaluated different interventions for visceral leishmaniasis in India, Nepal and Bangladesh (Das et al, 2008;Hirve et al, 2010;Huda et al, 2012;Singh et al, 2011). Three of the studies evaluated case detection and the other looked at three interventions (IRS, insecticide-treated nets and ecological vector management); all of them are observational studies.…”

Kala-azar (Visceral Leishmaniasis) Elimination in Bangladesh: Successes and Challenges

“…To improve the disease surveillance system, in 2011, the program initiated a camp approach for active detection of VL and PKDL cases in endemic villages. The camp approach has been found to be the most cost-effective intervention for active detection of cases with VL and PKDL [12]. One of the remarkable successes of the program is that for the first time, all VL endemic villages are mapped and stratified according to their VL endemicity (Fig.…”