Abstract:
A prospective study was undertaken during 2013 and 2014, to determine the prevalence
of African horse sickness virus (AHSV) in Culicoides midges and the incidence of infection
caused by the virus in 28 vaccinated resident horses on two equine establishments on the
East Rand, Gauteng Province, South Africa. Field caught Culicoides midges together with
whole blood samples from participating horses were collected every two weeks at each
establishment. Culicoides midges and blood samples were tested for the presence of
AHSV RNA by real-time quantitative reverse transcription polymerase chain reaction. Nine
immunised horses became infected with AHSV during the study period, although infections
were subclinical. African horse sickness virus was also identified from a field-collected
midge pool. The observations recapitulate previously published data in another setting,
where further investigation is warranted to determine what role subclinical infection plays
in the diseases epidemiology
