15 Mar 2021
After 12 months of epidemiological detective work, Small Animal Veterinary Surveillance Network researchers identify variant of canine enteric coronavirus as the probable cause of acute onset prolific vomiting.
James Westgate
Job Title
Canine coronavirus has been identified as the probable cause of a nationwide outbreak of prolific vomiting in dogs.
In January 2020 the Small Animal Veterinary Surveillance Network (SAVSNET) at the University of Liverpool asked the profession for help to collect data on a suspected outbreak after vets across the country began reporting cases of acute onset prolific vomiting (five or more episodes in a short 12-hour period).
Vomiting was more frequent than is typical for canine gastroenteritis and affected patients were so similar in presentation – diarrhoea and prolonged lethargy were also being reported – that vets began to suspect an infectious cause.
In just a month, researchers at SAVSNET received 1,258 case questionnaires from vets and owners while 95 clinical samples from 71 animals were also collected and – after 12 months of epidemiological detective work – a variant of canine enteric coronavirus (CeCoV) has been identified as the probable cause.
Dogs with prolific vomiting were found to be significantly more likely to test positive for CeCoV, while genetic testing on samples showed the CeCoV sequences from 14 of 16 dogs tested were identical, suggesting a single strain or variant geographically distributed across England.
Alan Radford, professor of veterinary health informatics at Liverpool and a member of the SAVSNET team, said: “We have known about canine enteric coronavirus for some time. However, it is generally associated with mild disease. Where it has been associated with severe disease it is usually sporadic, usually in younger animals and usually associated with other enteric pathogens.
“What was unusual in these cases was the severity of disease, in a wide range of ages and distributed widely across the UK. Although this type of science can’t prove this variant caused the outbreak, it does suggest an association between the two.”
SAVSNET began the investigation by using a system of collecting data from collaborating practices that features a unique main-presenting-complaint (MPC) window, which asks veterinary practitioners to select a syndrome (for example, gastroenteric, respiratory, pruritus) that best describes the animal’s reason for presentation.
Using this MPC, researchers found a specific and significant increase in the number of dogs recorded as exhibiting gastroenteric signs between late December 2019 and March 2020.
As well as reusing health records, SAVSNET also collected questionnaire data from vets and owners caring for affected animals, as well as healthy controls. This showed male dogs were more at risk than females.
Gina Pinchbeck, reader in veterinary epidemiology at Liverpool, said: “Analysis of case control data revealed male dogs, both neutered and entire, were at significantly increased odds of being a case, compared to neutered females.
“We were suspicious of either transmission between dogs or a common environmental source, as dogs in the same household as another dog that had also been vomiting were at significantly increased odds of being a case.”
