Enteric coronavirus infection in adult horses

Abstract

A new enteric virus of adult horses, equine coronavirus (ECoV), has recently been recognized. It is associated with fever, lethargy, anorexia, and less frequently, colic and diarrhea. This enteric virus is transmitted via the feco-oral route and horses become infected by ingesting fecally contaminated feed and water. Various outbreaks have been reported since 2010 from Japan, Europe and the USA. While the clinical signs are fairly non-specific, lymphopenia and neutropenia are often seen. Specific diagnosis is made by the detection of ECoV in feces by either quantitative real-time PCR, electron microscopy or antigen-capture ELISA. Supportive treatment is usually required, as most infections are self-limiting. However, rare complications, such as endotoxemia, septicemia and hyperammonemia-associated encephalopathy, have been reported, and have been related to the loss of barrier function at the intestinal mucosa. This review article will focus on the latest information pertaining to the virus, epidemiology, clinical signs, diagnosis, pathology, treatment and prevention of ECoV infection in adult horses.

Clinical presentation, diagnostic findings, and outcome of adult horses with equine coronavirus infection at a veterinary teaching hospital: 33 cases (2012–2018)

“…A recent seroprevalence study showed an increased proportion of ECoV infection in draft horses (17.6%), which was not apparent in the current study and likely reflects a difference in populations (Kooijman et al, 2017). Similar to other studies, ECoV infection rates were increased in the cooler months of the year, with peak prevalences in January through March likely related to husbandry changes and possible decreased viability of the virus in hot, dry temperatures (Kooijman et al, 2017;Pusterla et al, 2018).…”

“…Equine coronavirus (ECoV) is recognised as a cause of fever, anorexia, lethargy, leukopenia, and gastrointestinal disease in adult horses . Disease outbreaks have been reported in adult horses in boarding stables or competitive facilities across the United States, Europe, and Japan (Oue et al, 2013;Pusterla et al, 2013;Miszczak et al, 2014;Pusterla et al, 2018). The recent increase in positive cases likely reflects increased awareness of the virus, and increased availability and timeliness of testing through fecal real-time quantitative polymerase chain reaction (qPCR) (Pusterla et al, 2013).…”

Equine Coronavirus-Associated Colitis in Horses: A Retrospective Study

“…The breeds of the affected horses reflect those breeds seen at the WSU-VTH [14]. While most reports for this infection occur during winter [3], 3 of 5 horses in our study were admitted during the spring-summer. This is not surprising and reflects the sporadic nature of this infection [14].…”

“…The most common clinical signs observed in our study included anorexia, lethargy, and fever, all characteristic of this infection [2,3]. Changes in manure consistency (diarrhea and soft feces) were observed in all of the positive horses; interestingly, this is higher than previously reported [2e4,6].…”

“…This study describes the clinical presentation of horses that presented with clinical ECoV infection to a tertiary care facility, but were not associated with a known ECoV outbreak. This retrospective study only dates back to 2010 as this was the time when ECoV testing was included in routine fecal panels in laboratories around the country [3,7].…”