Health: Rotaviral Diarrhoea

Rotaviral Diarrhoea

Rotaviral diarrhoea is caused by a double-stranded RNA, non-enveloped virus of the family Reoviridae, genus Rotavirus.  This virus is one of the most common causes of foal diarrhoea in horse breeding centers around the world.  Infectivity and severity of disease generally decline with increasing foal age.  It is not considered to be a cause of diarrhoea in horses over the age of six months.  Equine rotavirus is transmitted via the fecal-oral route and damages the small intestinal villi resulting in cellular destruction, maldigestion, malabsorption, and diarrhoea.Vaccination of mares results in a significant increase in foals’ rotavirus antibody titers. 

The only available vaccine is conditionally licensed and is indicated for administration to pregnant mares to provide passive transfer of antibodies to foals against equine rotavirus. 

Vaccination Schedules:

Pregnant mares (vaccinated or unvaccinated): Administer a 3dose series of intramuscular vaccinations at 8, 9, 10 months of gestation. **It is essential that the newborn foal receives an adequate amount of colostrum and absorbs sufficient anti-rotavirus antibodies from rotavirus-vaccinated mares. 

Newborn foals: There are no data to suggest that vaccination of the newborn foal with inactivated rotavirus 

Other adult horses: Vaccination is unnecessary