Latest on SARS CoV-2 and COVID-19 and Pets
If we can figure out how cats do it, we may learn. It appears cats are surprisingly susceptible to the SARS Corona Virus-2 infection (SARS CoV-2), which causes COVID-19. Don’t worry. This fact doesn’t appear to be bad for cats, and it may benefit us.
Once infected with SARS CoV-2, their immune systems kick into high gear, nearly instantly effectively knocking out the virus according to a study published in the journal Emerging Microbes & Infections (published September 1, 2020). Various studies suggest double digit numbers when given positive test results using antibody testing – indicating lots of cats have built up an antibody response following exposure.
So, the evidence appears to be mounting that while cats are susceptible to SARS Co-V-2, they usually don’t get sick. But sometimes they might.
Increasingly over the past few months, there have been anecdotal reports of indoor cats with respiratory disease around the same time a family member (or more)is sick with COVID-19. Signs of illness almost always quickly dissipate without veterinary intervention. A study from Hong Kong identified SARS-CoV-2 by PCR in 12% of cats from COVID-19-positive households.
A big question from public health officials – can cats transmit SARS CoV-2 back to people, or even to other cats?
Thus far there is concern about cat to cat transmission, and while it appears plausible to have occurred (for example, even among big cats at the Bronx Zoo), it’s apparently a rare event. And thus far, no known confirmed reports among feral cat colonies.
As for cats transmitting the novel corona virus back to humans, so far, it hardly, it pretty much never occurs, even if it is theoretically possible. Clearly, SARS CoV-2 is a human virus which is nearly always spread among humans.
According to a study, SARS CoV-2 in Domestic Cats published August 6 in the New England Journal of Medicine, “With reports of transmission of SARS-CoV-2 from humans to domestic cats and to tigers and lions at the Bronx Zoo, coupled with our data showing the ease of transmission between domestic cats, there is a public health need to recognize and further investigate the potential chain of human–cat–human transmission. This is of particular importance given the potential for SARS-CoV-2 transmission between family members in households with cats while living under ‘shelter-in-place’ orders.”
Now for the Dogs
The Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) has been notified of the first confirmed Canadian SARS CoV-2 infected dog, happening in the Niagara region. The animal was tested as part of a research study, following diagnosis of COVID-19 in several people in the same household. This dog had no clinical signs of disease. A second dog in the same home had a borderline positive result on its rectal swab.
While veterinarians world-wide have treated a handful of cats with SARS CoV-2, even fewer dogs have been identified to be ill with the virus. In Hong Kong, early in the pandemic, they quarantined pets of COVID-19 patients who could not care for them (e.g. owner lived alone and had to be hospitalized), and all pets were tested at the quarantine facility. Hong Kong authorities identified SARS-CoV-2 in nasal, oral and/or rectal swabs from 2/15 dogs that were quarantined following exposure to their infected owners. Neither of the positive dogs had signs of infection, both developed antibodies to the virus, and gene sequencing of showed that the virus from the dogs was the same as that of their respective owners.
There is one report of an elderly Pomeranian dying as a result of a COVID-19 infection back in March. But there was no necropsy (animal autopsy) conducted, and the 17-year old dog also apparently suffered from heart disease which may have contributed to or even cause death, combined with advanced age.
Consider This Overview
Few people in Western nations relinquished pets because they’re worried about getting COVID-19 from their furry friend (which makes sense). Conversely, in many nations, including the U.S., pet adoption has been at an apparent all-time high.
Diagnostic labs Antech and IDEXX have now tested thousands of dogs and cats with only (according to my count) two cats in New York State testing positive for COVID-19 in the U.S. Add to this, a team of Tufts University researchers testing hundreds more animals looking for clues on whether they can get the virus and pass it along to humans, or vice versa – and no positives had been identified.
Absolutely, the number of pets tested is still relatively small, particularly among homes with people who have COVID-19. Now, doing some basic math: According to the Centers for Disease Control and Prevention, U. S. positives for COVID-19 are 8,617,022 and over 43.6 million positives for COVID-19 worldwide. Deaths around the globe due to COVID-19 are at over 1.1 million with nearly 225,000 from the U.S. and with all that only less than a handful of companion animals have succumbed to COVID-19, and most of those even uncertain. Even the positively identified companion animals remains absolutely minuscule compared to the impact on human numbers.
It seems clear this is a human problem.
Having said that, the American Veterinary Medical Association and World Small Animal Veterinary Association are among those that strongly suggest, out of an abundance of caution, if someone in your home is positive for COVID-19, ideally isolate that person from the pets, allowing other family members to take over interacting and caring for furry family members. Or consider sending the pets (many dogs may actually enjoy this) off to a friend or neighbor’s house for a mini-vacation.