Visceral Leishmaniasis Eradication is a Reality: Data from a Community-based Active Surveillance in Bangladesh

More than 20 million people in Bangladesh are considered at risk of developing visceral leishmaniasis (VL). A community-based active surveillance was conducted in eight randomly selected villages in a highly endemic area of Bangladesh from 2006 to 2008. A total of 6,761 individuals living in 1,550 mud-walled houses were included in the active surveillance. Rapid rK39 dipstick tests were conducted throughout the study period to facilitate the case diagnosis. Individuals with previous or current clinical leishmaniasis were identified on the basis of the case definition of the VL elimination program. Untreated cases of suspected VL were referred to the hospital for treatment. Socioeconomic and environmental information including bed net use was also collected. In 2006, the annual incidence of clinical leishmaniasis in the study area was 141.9 cases per 10,000 population, which was significantly increased by the following year owing to community-based active surveillance for case detection and reporting. However, early case detection and early referral for treatment led to a significant decrease in incidence in 2008. This study suggests that community-based active surveillance using a simple diagnostic tool might play a role in achieving the goal of the VL elimination program.

rK39 enzyme-linked immunosorbent assay for the diagnosis of Kala-Azar in an endemic zone of

The diagnostic role of rK39 enzyme linked immunosorbent assay [ELISA] was compared with the buffy-coat Leishmania nested polymerase chain reaction [Ln-PCR] for kala-azar in an endemic zone of Bangladesh. This evaluation study included 100 cases comprising of 60 clinically suspected patients of kala-azar and 40 healthy controls. Anti-rK39 antibody was estimated in plasma by ELISA and buffy coat was utilized to detect Leishmania DMA by Ln-PCR from both patients and controls. The diagnostic role of rK39 ELISA was then compared with Ln-PCR positive cases which were considered as confirmed cases of kala-azar. Out of 60 suspected patients of kala-azar, 58 [96.67%] were found positive in ELISA against 56 [93.33%] of Ln-PCR-positive cases. Further, 55 [98.21%] of ELISA-positive patients were also found positive in Ln-PCR. Voluntary healthy controls [40] included 20 persons from the endemic zone and 20 from non-endemic zone of kala-azar, were all found negative in both Ln-PCR and rK39-ELISA. The sensitivity and specificity of ELISA were found to be 98.21% and 95.65% respectively. rK39-ELISA is a non-invasive serodiagnostic tool for visceral leishmamasis with very high sensitivity and specificity