SERO-PREVALENCE OF BLUE TONGUE VIRUS IN SMALL RUMINANTS OF THE STATE OF ASSAMN.N. BARMAN, D.P. BORA, T.K. DAS, S.K. BISWAS, S.M. GOGOI, P. PATHAK AND S.A. ARIF
Bluetongue (BT) is an economically devastating viral disease transmitted to domestic and wild ruminants by certain species of Culicoides midges. In the recent years, BT has spread beyond the historically recognized geographical limits and there has been emergence of novel genotypes. Changes in the vector epidemiology and the potential for emergence of new vector species raises concerns of further spread. This study, therefore, was conducted to assess the seroprevalence of Bluetongue virus (BTV) in goats and sheep of Assam. A total of 671 sera samples were collected from goats and sheep belonging to different agroclimatic zones of Assam irrespective of age, sex and breed. The samples were screened for presence of BTV specific antibodies using indirect Enzyme Linked Immuno Sorbent Assay (iELISA). The locations of the study sites were marked using a GPS device and GIS facilities were used to correlate the disease prevalence with geo-climatic conditions. Out of 671 sera samples, 304 (45.31%) were found to be positive for the presence of BTV antibody out of which 295 (46.97%) samples were from goats and 9 (20.93%) from sheep. Among the six agro-climatic zones of Assam, the highest prevalence was detected in the Hills region (91.00%) and the lowest in the Central Brahmaputra Valley (25.00%). The seropositivity observed in this study herein calls for extensive surveillance for detecting the virus incursion in the entire susceptible host range and also for studying the vector population in order to implement comprehensive strategies to predict and control BTV occurrence.