Seroprevalence of Bluetongue and Schmallenberg viruses in ruminants in Al-Batinah Governorates, Oman

Abstract

Bluetongue (BTV) and Schmallenberg viruses (SBV) are the causative agents of Bluetongue and Schmallenberg dis-eases, respectively. Both BTV and SBV are vector-borne viruses that are transmitted mainly by Culicoides (Diptera; Ceratopogo-nidae) and infect do-mestic, wild ruminants, and camelid species. Bluetongue virus be-longs to the genus Orbi-virus, family Reoviridae, whereas Schmallenberg virus belongs to the ge-nus Orthobunyavirus, family Bunyaviridae. In this study, we used en-zyme-linked immuno-sorbent assay (ELISA) to determine the sero-prevalence of both vi-ruses in ruminants in Al-Batinah Gover-norates, Sultanate of Oman. A total of 529 serum samples were randomly collected from 207 sheep, 265 goats, and 57 cattle from five wilayat of Al-Batinah North and Al-Batinah South Governorates. The serum samples were screened for the presence of BTV-specific antibodies against the BTV VP7 protein using ID Screen® Bluetongue Competition (cELISA) and screened for the presence of SBV-specific antibodies against the recombinant SBV nucleoprotein anti-gen using ID Screen® Schmallenberg virus Indirect Mult (iELISA). The overall seropreva-lence of BTV and SBV infections was 69.8% and 44.8%. In cattle, the prevalence of BTV and SBV antibodies was comparatively higher (94.7% and 82.5%) than in goats (83% and 43%) and sheep (45.9% and 36.7%). The high-est BTV seroprevalence was recorded in Nakhal (85.5%), followed by Wadi Al-Maawil (81%), and was lowest in Bar-ka (59.6%). However, the highest seropreva-lence of SBV was ob-served in Wadi Al-Maawil (50%), followed by Barka (48.7%), and lowest in Sohar (34.2%). Overall, the seroprevalence of BTV and SBV in domesticat-ed ruminants was high-er in adults than in young animals. Females showed a higher sero-prevalence of BTV and SBV compared to males. The study pro-vides an update on the epidemiological status of BTV, and to our knowledge, this is the first study on the sero-prevalence of SBV in ruminants in Oman. Future studies are re-quired for the isolation and identification of BTV and SBV along with other potential bio-logical vectors in Oman.