Visceral leishmaniasis in southeastern Nepal: A cross‐sectional survey on Leishmania donovani infection and its risk factors

Abstract

Summaryobjective To document the frequency of Leishmania donovani infection at community level in a highly endemic region in southeastern Nepal, and to assess socioeconomic and environmental risk factors.methods A random cross-sectional population survey was held in two visceral leishmaniasis (VL) foci in Morang District in April to May 2003, enrolling individuals 2 years or older and residing in the endemic area for at least 12 months. Leishmania infection was defined as a direct agglutination test (DAT) titre equal to or higher than 1:3200. Risk factors were identified by logistic regression.results The direct agglutination test was positive in 7.5% (95% CI: 5.1-10.8) and the leishmanin skin test (LST) in 13.2% (95% CI: 9.9-17.2) of the 373 study participants. No case of current kala-azar was found, but 5.1 % (95% CI: 3.1-7.8) reported having suffered from VL. Independent risk factors for Leishmania infection were proximity of the house to ponds [odds ratio (OR) 3.7, 95% CI: 1.6-8.5], family size (OR 4.4, 95% CI: 1.6-12.6), age P15 years (OR 5.5, 95% CI: 1.2-25.0) and house constructed in mud (OR 3.0, 95% CI: 1.1-7.6). Bednets, not impregnated and in poor condition, were used by 95.2% (95% CI: 92.3-97.0) of the population, but did not show any protective effect.conclusion This study shows that there is a serious problem of transmission of VL in this area of Nepal. The risk factors identified are linked with the socioeconomic level and the environment. The population would benefit from a community intervention to improve the environmental and housing conditions in the villages.keywords visceral leishmaniasis, Leishmania donovani, leishmanin skin test, environmental risk factors, Nepal

Reassessment of Immune Correlates in Human Visceral Leishmaniasis as Defined by Cytokine Release in Whole Blood

“…The IGRA results can be compared only to the imperfect standard of serology. As found in previous studies comparing the Leishmanin sensitization test (LST) with serology (3,27), we also found a higher positivity rate in the IGRA compared to DAT and rK39 ELISA. The greater sensitivity of IGRA to detect asymptomatic infection might be explained by the fact that antibodies are thought to wane earlier than cellular immunity.…”

Usefulness of the rK39-Immunochromatographic Test, Direct Agglutination Test, and Leishmanin Skin Test for Detecting Asymptomatic Leishmania Infection in Children in a New Visceral Leishmaniasis Focus in Amhara State, Ethiopia

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“…These methods have been based on the direct agglutination test (DAT), rK39-immunochromatographic test (rK39-ICT), enzymelinked immunosorbent assay, indirect immunofluorescent antibody test, or Western blot. [8][9][10][11][12] The LST is a useful method for detecting cell-mediated immunity against Leishmania. Results for this test become positive after subclinical infection and, in this case, persist much longer than antibodies against Leishmania.…”

The Relationship between Leishmaniasis and AIDS: the Second 10 Years

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