Much has been reported about the 17-year-old Pomeranian in Hong Kong that was the first dog to test positive for SARS-CoV-2, the virus that causes COVID-19. It was positive on a series of PCR tests on nasal and oral swabs over the first week it was in quarantine. They also collected blood samples to test for antibodies against the virus. The blood first tests were negative, which wasn’t too surprising, but was taken by some to mean the dog wasn’t infected (just “contaminated” with virus such that there was no immune response). However, subsequent testing of a sample taken back on March 3 showed that the dog did indeed produce antibodies against the virus, and therefore was definitely infected at some level. Unfortunately, as previously mentioned, the dog died a few days after being released from quarantine (it’s not suspected that its death had anything to do with its infection with SARS-CoV-2).
The update from the Hong Kong Agriculture, Fisheries and Conservation Department also provides some more information about other testing they’ve done to date. They have tested 17 dogs and 8 cats from households with human COVID-19 infections, and two of the dogs tested positive. It’s interesting (and encouraging) that no cats have tested positive so far, since I’ve had more concerns about the susceptibility of cats, but finding positive results in 2 out of 17 dogs definitely tells me we need to study this more.
This report doesn’t tell us whether dogs and cats are a source of infection, because being infected doesn’t necessarily mean an individual is infectious (i.e. able to pass the virus on). We need to test more animals to see how common infection is and whether live virus can be recovered from infected animals. Unfortunately getting samples from households of infected people with pets has been a challenge due to the social distancing and human-to-human transmission concerns (which are clearly paramount).