Although we are dealing with a corona virus pandemic in humans, horses can also get sick with a different corona virus.  In horses, it is accomplished by testing the feces.  A PCR test is used similar to the onsite testing of sick people for COVID-19 but of course that test is usually performed on oral and nasal swabs.  It is believed the equine test is accurate in cases with a positive test result and clinical signs of equine corona virus, which include fever, decreased appetite, lethargy and diarrhea due to colitis.  However, these are common signs so other diseases must be ruled out.  The Horse publication indicates a recent study at Washington State tested 130 hospitalized horses for the corona virus at a teaching hospital and that half of the horses were at the hospital for a gastrointestinal illness while the other half had other diseases or were there for some elective surgery.  Results indicated only one horse was positive in the feces for corona virus, and that horse was admitted for a gastrointestinal disease.  This study indicates that corona virus is not commonly found in horse’s feces, and if it is found it is likely significant. 

Equine corona virus affects the intestinal tract of horses and causes colitis, diarrhea, fever, decreased appetite, and lethargy. It is contagious to other horses but not to people or other species.  And although this is a beta corona virus similar to COVID-19, it does not affect the respiratory system as COVID-19 does in people.  Bovine corona virus causes winter dysentery and respiratory disease in calves, so there are lots of corona viruses in animals and people, and testing for them is common.  It seems the fecal test for equine corona virus is a fairly accurate test if the horse has clinical symptoms.