As someone who works in zoonotic diseases and One Health, I deal with the ever-present issue of trying to raise awareness while preventing people from over-reacting, panicking or doing something stupid. It can be tough, since we want people to realize that animal-to-human transmission of infections is an important issue, but don’t want them huddling in their bathrooms afraid that their pet is going to somehow kill them.

We’ve had repeated examples of both sides of this when it comes to SARS-CoV-2 in animals, while trying to get agencies to pay attention to potential zoonotic transmission risks and also trying to prevent them for over-reacting. There’s a sweet spot in between, but it often gets missed.

Today’s report of Hong Kong’s plan to kill thousands of small mammals is an example of a huge miss.  Hong Kong did a great job regarding animal aspects of SARS-CoV-2 at the start of the pandemic by proactively quarantining and testing pets of people with COVID-19, and that helped us understand a lot about the disease in dogs and cats. Their proactive approach decreased over time, logically based on evolving information, so this extreme reaction now is a bit surprising.

What triggered this response?  Infection of a person – the origin of most SARS-CoV-2 infections in animals.

Here’s how the story goes.  A pet shop worker was identified with COVID-19 caused by the delta variant. Another person with COVID-19 reported visiting the store around the same time, and her daughter had handled a hamster. In response to that, officials tested hundreds of animals at the workplace.

That’s fine.  Actually, that’s great, since it can provide us with more information about human-to-pet transmission risks.

  • 11 infected hamsters were identified
  • Other species all tested negative

However, the subsequent response to the test results was the problem.

  • ~2000 small mammals across 34 different pet stores and housing facilities will be euthanized.
  • Anyone who purchased a hamster after December 22 will be required to surrender the pet to authorities for euthanasia. (A “hamster hotline” has even been set up for this.)

Does this response make sense?

No. It’s good to pay attention to and evaluate risks, but too often “kill the animal” is the “easy” response to something that just needs some thought and effort.

What could feasibly be done instead?

Small mammals are very easy to isolate safely. If there’s concern, they could quarantine the animal facilities or stores, do some more testing and handle things with basic infection control measures. The risk wouldn’t be zero (there’s rarely a scenario with zero risk when it comes to infectious diseases) but the risk would be exceptionally low, animals wouldn’t be unnecessarily killed, and we’d get more important information about this virus in animal populations.

Hamsters, like other susceptible species, don’t shed the SARS-CoV-2 virus for long when they’re infected. So, short term isolation would allow the virus to be naturally eliminated in an individual hamster or group. Yes, it takes some time, effort and possibly money, but those would be pretty limited, and it would also spare animal owners having to give up their pets.  The risk, costs and time required to track down and euthanize all the animals might be greater than would be required to isolate them.