“I was wondering if you or anyone else may know,” the email began. Of course the questions that followed were about the novel coronavirus that causes COVID-19. Are dogs and cats susceptible? Could the pet food she usually buys, which is manufactured in Italy, transport the disease? “It occurred to me, “ she wrote, “that if someone at the dry food plant went to work, and didn’t know that they were infected with the virus, and they sneezed or coughed, perhaps the food could infect the pets who eat it?” An interesting question. Later that evening, when I arrived at a social gathering, COVID-19 continued to be the topic of conversation. Rumors flying. Wasn’t there a case in Chilmark? (No, just healthy people self-quarantining after travel to Italy.) Wasn’t there an infected dog in Hong Kong? Well, sort of … but don’t freak out, at least not any more than you already have.
Let’s talk about COVID-19 and pets. First we’ll define our terms. The organism in question is a brand-new variant of coronavirus, technically called SARS-CoV-2. For simplicity we will just call it “coronavirus” today, remembering that there are many other variants of coronavirus in the world unrelated to the current situation. The disease caused by SARS-CoV-2 is COVID-19 (short for coronavirus disease 2019).
The pet food question breaks down into two parts. The first part is whether coronavirus could be physically transported via bags of pet food from a factory in Italy to a home in West Tisbury. The bigger question is whether (and how long) coronavirus can survive on objects. Think of all the packages containing all the products made in China, or Italy, or the State of Washington, being shipped around the world every day. Preliminary studies suggest the virus may persist on surfaces for a few hours or up to several days, depending on conditions such as type of surface, and environmental temperature or humidity. According to the World Health Organization, “The likelihood of an infected person contaminating commercial goods is low, and the risk of catching the virus that causes COVID-19 from a package that has been moved, traveled, and exposed to different conditions and temperature, is also low.”
The second part of the question is whether Pandy, the puppy, can be infected and/or transmit the virus to his owner. Here is the evidence to date at the time this column went to press. A single dog in China was placed in quarantine after its owner was confirmed sick with COVID-19. According to Hong Kong’s Agriculture, Fisheries and Conservation Department, the dog was repeatedly tested over five days. Three of these tests showed a “weak positive,” indicating “a low level of infection with the virus.” The dog has shown no signs of illness.
Initially the specialists stated, “The implications of a ‘weak positive’ test result are unclear, and it’s unknown if the presence of the virus is due to infection, environmental contamination, cross-reactivity, or even potential issues with the test itself.” Later statements from experts from the School of Public Health of the University of Hong Kong, the College of Veterinary Medicine and Life Sciences of the City University of Hong Kong, and the World Organization for Animal Health “unanimously agreed that these results suggest that the dog has a low level of infection, and it is likely to be a case of human-to-animal transmission.” In other words, the owner infected the dog, not the other way round. And the dog did not get sick.
So could that dog then pass the virus on to another person? The current thinking is that dogs are not likely to be “important epidemiologically in the spread of COVID-19.” There is no evidence at this time of pet-to-person transmission. If dogs had been an important source of transmission to humans, there would almost certainly already be significant evidence of this in mainland China. Sadly, in some parts of the world, people are actually abandoning or euthanizing their pets despite these facts.
Of course, Pandy the puppy could theoretically carry virus on his fur, just like any object can, be it a doorknob or a bannister. This could occur only from direct contact with an infected human, such as a sick person petting Pandy with a contaminated hand. Thus, current recommendations are that if you are sick, avoid contact with your pets. No petting and snuggling. No doggie kisses. No face licks. No sharing food. If you can, let someone else who isn’t sick take care of the pets. If you have to interact with Pandy while ill, use the same precautions against passing on the virus as you would with humans, such as wearing masks and washing hands.
There is also misinformation being spread about veterinary vaccines. The canine coronavirus vaccine and the bovine coronavirus vaccine are for completely different variants than SARS-CoV-19, and are species-specific. Neither vaccine will protect any animal — dog, cow, or human — against COVID-19, no matter what you read on Facebook. Neither are these vaccines safe to use in people.
“I was wondering if you or anyone else may know,” my client wrote. We are all wondering that these days. This is still an emerging disease, with rapidly evolving information. As far as veterinary advice, I advise that you simply follow the Center for Disease Control (CDC) recommendations. If you are sick, minimize contact with your pets as well as with people. In the unlikely case your pet develops an unexplained illness after contact with a person with a confirmed case of COVID-19, keep your pet and yourself at home. Contact your local public health official and your veterinarian. Talk to them before actually bringing your pet into a veterinary clinic, so they can advise you as to how to handle the situation based on the most current knowledge. Include your pets in any emergency preparedness planning, including having a two-week supply of their food and essential medications on hand. Take care of yourselves. Take care of each other. Take care of your pets. And wash your hands.