Equine Coronavirus (ECoV) is circulating in Ireland’s horses and foals, researchers report.
It is the first detection of the virus in the country, with Ireland becoming the third European country with a significant horse industry where the virus has been detected, based on testing in horses with intestinal disease.
ECoV infection can cause fever, loss of appetite, lethagy and diarrhoea. It can also cause respiratory problems.
Scientists believe it spreads through horse’s mouths coming into contact with the dung of infected horses.
The infection has been identified in horses in 48 American states. In central Kentucky, it was found that about 30% of both healthy and diarrheic Thoroughbred foals were infected.
For their study, Manabu Nemoto, Warren Schofield and Ann Cullinane tested 424 clinical samples – faecal samples and rectal swabs – from equids with gut-related disease. The samples, collected from 2011 to 2015, were spread across 24 Irish counties.
Molecular-based testing revealed that five samples (1.2%) collected in 2011 and 2013 tested positive for ECoV.
The positive samples were collected from adult horses, Thoroughbred foals and a donkey foal, the trio reported in the journal Viruses.
“This is the first report of ECoV detected in both foals and adult horses in Ireland,” they said.
However, the researchers stressed that detection of ECoV in faecal samples from horses with intestinal disease did not prove causation.
“In this study, 424 samples collected between 2011 and 2015 from equids with enteric disease were tested, and only five samples (1.2%) were positive for ECoV.” This low prevalence is similar to that identified in France and among Thoroughbred foals in Japan, they noted.
The researchers noted genetic changes that indicated that the Irish viruses were distinguishable from those circulating in other countries, and were genetically closely related to the Japanese viruses.
The authors say many questions remain over the clinical significance of ECoV
“It has been suggested that ECoV is a co-infecting agent in foals with diarrhoea and clinical infections have predominantly been reported in adult horses with a mono-infection with EcoV.”
However, there was no indication from the results of this study that coronavirus was a major cause of diarrhoea in Irish horses, they said.
They suggest that adult horses with a loss of appetite, lethargy, fever and changes in faecal character should be tested for the virus, as a significant association has been shown between this clinical status and molecular detection of ECoV in faeces.
The First Detection of Equine Coronavirus in Adult Horses and Foals in Ireland
Manabu Nemoto, Warren Schofield and Ann Cullinane.
Viruses 2019, 11(10), 946; https://doi.org/10.3390/v11100946