Serosurvey of peste des petits ruminants in small ruminants in the hilly terrain north-eastern state of Sikkim in India.

Abstract

This cross-sectional serosurvey outlines the seroprevalence of peste des petits ruminants (PPR) in small ruminants in the hilly terrain north-eastern state of Sikkim in India. A total of 776 small ruminants’ (sheep [n = 99] and goats [n = 677]) serum samples were collected from 62 epidemiological units (epi-units) of the state using a two-stage sampling method from September 2017 to February 2018. The collected sera were screened for the small ruminant morbillivirus (SRMV) antibodies using a PPR-competitive enzyme-linked immunosorbent assay (cELISA). The results showed 1.16% (95% confidence interval [CI]: 0.61-2.19%) apparent prevalence with almost zero calculated true prevalence, which implies the insignificant prevalence of SRMV antibodies in the small ruminants population. Further, only a few samples from <5 % epi-units have shown positive for SRMV antibodies with an overall seropositive of <30% in the surveyed epi-units in Sikkim. This report is first of its kind on the seroprevalence of PPR in a unique niche of hilly terrain settings and it implies that SRMV has not yet become established in the small ruminants in Sikkim, despite the enzootic nature of the disease in the rest of India. This necessitates the imposing of strict quarantine measures and restrictions in the small ruminants trade along with the implementation of the intensive active surveillance programme to make a PPR free state.