Applicability of direct agglutination test (DAT) at a rural health setting in Bangladesh and feasibility of local antigen production

Arch Inst Pasteur Tunis. Jul-Oct 1993;70(3-4):333-44.

Abstract

As part of a large-scale sero-epidemiological survey on visceral leishmaniasis (VL) carried out in Mymensingh district of Bangladesh, applicability of DAT was assessed at the level of a rural health setting in Trishal (upazila) subdistrict. Despite the relatively less optimal conditions encountered, 5854 inhabitants from 7 villages appendant to Trishal were assessed for VL. The demographic distribution for sero-positivity obtained at the rural setting was comparable to that found by DAT as executed at the central laboratory (IEDC&R, Dhaka) on 9619 inhabitants from the same upazila. The overall sero-prevalence rate was 4.4% compared to 3.7% obtained in the population assessed at the central laboratory. In either study, similar VL prevalence rates of 2.1% were obtained in the male populations. Irrespective of sex, younger population (< 20 years) in both studies appeared to have higher VL incidence rate (2.3% and 2.6%) than others of 21- > or = 90 years (1.4% and 1.8%). Local production of DAT antigen employing an authochtonus L. donovani isolate was attempted at the central laboratory (IEDC&R) in Dhaka. By comparison with the reference antigen, titres obtained in all 33 VL sera tested were equally higher (1:6400- > or =: 51200) than in 35 out of 38 negative controls (< or = 1:400-1:1600). A comparable level of reactivity was also obtained in 53 VL and 52 negative control sera using a well characterized L. donovani strain (MHOM/IN/80/D88) from India. However, unlike the reference strain, titres obtained in 7 endemic controls were significantly higher with the authochtonous and homologous antigen (1:3200 - 1:6400) than with the reference (1:100 - 1:1600). The results signify the advantage of employing indigenous L. donovani isolates to further improve DAT sensitivity for detection of early and sub-clinical VL.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Agglutination Tests / methods*
  • Animals
  • Antigens, Protozoan / blood*
  • Bangladesh / epidemiology
  • Case-Control Studies
  • Child
  • Child, Preschool
  • Feasibility Studies
  • Female
  • Humans
  • Infant
  • Leishmania donovani / immunology*
  • Leishmaniasis, Visceral / blood*
  • Leishmaniasis, Visceral / epidemiology*
  • Male
  • Middle Aged
  • Population Surveillance / methods*
  • Prevalence
  • Rural Health*
  • Sensitivity and Specificity
  • Seroepidemiologic Studies

Substances

  • Antigens, Protozoan