Volume 96, Issue 6
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



Several epidemiological studies have indicated the presence of asymptomatic infections with in the Indian subcontinent, where parasite transmission is considered anthroponotic. In India, such asymptomatic cases have been identified in the state of Bihar. We explored here, the presence of asymptomatic infection among healthy individuals living in two districts in the state of West Bengal, India, using serological and molecular tests. Blood samples of 246 healthy individuals were collected from nine villages of Malda and Murshidabad districts in West Bengal, considered endemic for visceral leishmaniasis (VL). Real-time quantitative polymerase chain reaction (qPCR) was performed for the quantification of parasite load in the blood. In addition, two serological tests were carried out to demonstrate anti- antibodies: rK39 strip test and anti-total soluble antigen IgG using enzyme-linked immunosorbent assay method. Nearly one-fifth (53/246) of the screened population was positive in qPCR as against 10.97% (27/246) positive in rK39 strip test. A range of parasite load was observed in the blood of identified asymptomatic cases with a median value of 7.7 parasites/mL (range = 1–65). There was poor agreement between qPCR and serological tests (κ = 0.089, = 0.13), and 29.62% and 20.54% of the population were qPCR positive in seropositive and seronegative groups, respectively. Combined molecular and serological tests enhanced the capacity to detect asymptomatic infection in healthy individuals residing in the endemic areas of VL. A significant proportion of asymptomatic individuals was detected in the examined endemic regions of West Bengal that might play a role in promoting VL transmission.


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  • Received : 20 Jul 2016
  • Accepted : 19 Dec 2016
  • Published online : 03 Apr 2017

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