English abstract
Bluetongue (BTV) and Schmallenberg viruses (SBV) are non-contagious, non-zoonotic
and vector-borne diseases. Both viruses infect domestic and wild ruminants and camelid
species, and are transmitted mainly via Culicoides spp. Bluetongue virus belongs to the
genus Orbivirus, family Reoviridae, whereas Schmallenberg virus belongs to the genus
Orthobunyavirus, family Bunyaviridae. In Oman, only two studies were conducted in
1991 and they investigated the seroprevalence and detected different serotypes of BTV.
There is no available data about SBV seroprevalence in Oman. This study aims to
investigate the seroprevalence and associated potential risk factors of BTV, SBV and
cross infection in sheep, goats and cattle in Al-Batinah Governorates, Sultanate of Oman
using ELISA. A total of 529 serum samples were randomly collected from 207 sheep,
265 goats and 57 cattle from five wilayats of Al-Batinah north and Al-Batinah south. The
serum samples were screened for the presence of BTV specific antibodies against the
BTV VP7 protein using ID Screen® Bluetongue Competition enzyme-linked
immunosorbent assay (cELISA) and screened for the presence of SBV specific antibodies
against the recombinant SBV nucleoprotein antigen using ID Screen® Schmallenberg
virus Indirect Multi-species screening test (iELISA). The overall seroprevalence of BTV,
SBV and cross infection were 69.8% (369/529), 44.8% (237/529) and 36.9% (195/529),
respectively. In cattle, the prevalence of BTV and SBV antibodies was comparatively
higher (94.7% and 82.5%) than in goats (83.0% and 43.0%) and sheep (45.9% and
36.7%), respectively. The highest BTV seroprevalence was recorded in Nakhal (85.5%)
followed by Wadi Al-Maawil (81.0%) and lowest in Barka (59.6%). However, the
highest seroprevalence of SBV was observed in Wadi Al-Maawil (50.0%) followed by
Barka (48.7%), and lowest in Sohar (34.2%). Overall, the seroprevalence of BTV and
SBV in domesticated ruminants was higher in adult than young animals. Females showed
a higher seroprevalence of BTV and SBV compared to males. The study provides an
update on the epidemiological status of BTV and to our knowledge; this is the first study
on the seroprevalence of SBV in Oman. Future studies are required for the isolation and
identification of BTV and SBV along with other potential biological vectors in Oman.
