LEISHMANIA DONOVANI AND WUCHERERIA BANCROFTI CO-INFECTION IN AN ASYMPTOMATIC POPULATION OF VISCERAL LEISHMANIASIS

Abstract

Intro: Co-infection with Leishmaniasis and filariasis can occur in an endemic population. The immunological modulation triggered by filaria infection could influence the clinical manifestations and progression of both disorders. The aims of the study were to assess the prevalence of filarial infection in asymptomatic Leishmania donovani infected individuals and their correlation of filarial co- infection with progression to Visceral Leishmaniasis (VL) illness. Methods: TaqMan-based quantitative polymerase chain reaction (qPCR) assays were used to detect filarial species, Wuchereria banchrofti and Leishmanial species, L. donovani in 1265 individuals of serologically positive [serologically negative in 1st serosurvey (DAT 14PP with an increase of at least 2 titres in DAT and 3 PP in ELISA from the 1st Serosurvey)] and serologicaly negative [serologically negative (both DAT (titre <1:1600) and rk39 ELISA PP less than cut-off PP i.e. 14 PP in both serosurvey 1st and 2nd] Leishmania infected healthy individuals (Asymptomatic,) living in endemic region Muzaffarpur district Bihar, India. Findings: 465 (36.75%) Individuals were infected with L. donovani and 99 (7.82%) had Wuchereria banchrofti infection in which 33 were co-infected. After fallow up Seventeen individuals progress to symptomatic VL in which 6 (18.0%) from co-infected, 3 (0.07%) from L. donovani DNA positive individuals and 8 (1.1%) from non-infected individuals. Conclusion: This study shows the high probability in progression of asymptomatic subjects that are already infested with Filariasis to clinical VL condition due the increased severity of VL-filarial co-infection. As an important consequence, Filarial disease exposure through mass drug administration (MDA) may be an important way to reduce the transmissibility of Filarial and progression of clinical VL infection to people.