I’ve spent more time than I can count on calls about COVID-19. Lots of questions about animal aspects come up and there are few good answers. Too often, there’s a desire to come up with definitive statements, despite the lack of evidence. That’s been done by some groups, and then they’ve had to walk those back (e.g. “there’s no evidence pets can be infected” changed to “there’s no evidence that pets can get sick or infect people”).
I’ve ranted about the “absence of evidence” vs “evidence of absence” concept here a bit (and a lot more on calls). I appreciate the desire to reassure people. We don’t want them freaking out and we want to emphasize that the risk posed by pets is minimal, if there even is a risk. However, we have to be honest about what we know and what we don’t know. I try to be clear about that because I want my opinion to be understood and for people to have confidence in what I say. I realize what I say might change, but I want to make sure that when I say something definitively, that there’s little chance I’ll have to walk it back. We need to accept a degree of uncertainty – that’s easier said than done, but we can’t let uncertainty scare us or stop us from acting. If we wait for definitive information, we’re bound to miss important opportunities.
Okay… enough ranting (or whining). Let’s go over some of our areas of uncertainty. Remember that uncertainty doesn’t mean we can’t do anything – we still have to act. It means we have to make our best informed guess (based on our knowledge of the basic principles of disease control) and realize that things might change.
Can animals be infected with the COVID-19 virus?
I think we can say “yes” for dogs. I’d say “probably” for cats. Few cats have been tested but since dogs can be infected, and cats are thought to be better hosts than dogs, it’s likely cats can be infected too.
Can infected animals infect people with the COVID-19 virus?
That’s the big question, and we really don’t know. The risk is probably low, but we can’t say it’s zero. If an animal is infected, it might have such a low level infection that it doesn’t pose a risk for transmission. An example of this is human influenza in dogs. We can pass human influenza virus to dogs (it’s rare but it happens), but we consider them “dead end hosts” – they are infected, but since it’s not their flu virus, they don’t produce enough virus to pass it along to others. Hopefully, that’s the case with this virus. I’m not too concerned about dogs. I still have concerns about cats, based on what we know about SARS.
What should we do with dogs/cats from households with infected people?
Keep them in the house. If we keep them away from other people and animals, we don’t need to worry about whether they are infectious (because the people in the house are by far the greater risk).
If we have to move a pet from an infected household (e.g. to take them to a vet if they are sick) we run into a lot of questions focused on two issues: 1) whether they can be truly infected (see above), and 2) whether their haircoat can be contaminated (see below).
Can a pet’s haircoat be contaminated withe the COVID-19 virus and then infect people?
It’s a reasonable concern. The contamination part could certainly happen, and I wrote about environment survival of COVID-19 virus the other day, but we don’t know how long the virus might survive on a haircoat. Presumably, it could survive for a few hours, maybe a bit more. So, if an animal comes into a clinic or shelter directly from a household with an infected person, it’s prudent to assume there’s some virus on the haircoat. The question is, is it enough to infect a person handling to pet. That’s what we really don’t know.
What should be done about a pet with a potentially contaminated haircoat?
I get this questions countless times a day. I wish I had a great answer.
Since it’s a reasonable concern, we should take precautions, while still trying to be prudent about our use of personal protective equipment, as supplies are running low. Some have suggested just using hand hygiene, but I’m not comfortable with that. In shelters in particular, people with limited infection control training are the first line handlers in some situations, and limited precautions with limited training isn’t a good combination.
At the moment, I recommend a gown, gloves, mask and eye protection. I think we can probably get by without the mask and eye protection if there’s limited contact (e.g. just taking an animal and moving it to a kennel) and if we’re careful about what we do. A mask and eye protection help prevent hand-to-mouth/eye contact as much as anything else. Decreasing the amount of protective equipment is reasonable in some situations but it’s dependent on a good understanding of what can and can’t be safely done, and good compliance with those guidelines. The less experience and training the person has, the less I’m comfortable decreasing the level of precautions.
Ideally, an animal from a high risk house is quickly and safely transferred to a cage and left alone as much as possible for a few days, at which point there’s pretty much no risk of viable virus remaining on the haircoat. We can’t always do that, though, especially with sick animals in vet clinics.
What about bathing the animal or using something else to kill the virus on the haircoat?
Bathing, topical application of chlorhexidine mousse, topical chlorhexidine (or other biocide) rinses or wiping with a disinfectant wipe would probably help, but can’t be used in all situations. For example, you shouldn’t try to bathe a dog with an unstable pelvic fracture. However, some form a topical treatment can probably be used. It’s easy, cheap, safe and might help, though remember it is no guarantee the animal’s coat will then be completely virus-free. If nothing else, a quick wipe of common human hand contact surfaces on the pet (e.g. the top of the head) with a disinfectant (e.g. accelerated hydrogen peroxide) wipe would be reasonable (and safe).
What is the risk from pets from other households?
Relax! The odds of a pet from a household without known or presumed human case of COVID-19 being infected are exceedingly low. Don’t waste precious protective equipment. Wash your hands. Business as usual.
What should shelters do if someone wants to surrender a dog/cat because of COVID-19 fears?
Step 1 is to talk to the owners about their concerns. In many cases we can address fear and panic with the information we have, even if we still don’t have all the answers. The risk of infection from someone’s own pet is very limited. If my dog Merlin had this virus, he would have gotten it from me or someone else in my family. So, I’m either already infected or am more likely to get it from my biohazardous wife or kids. If we can’t talk the owner into keeping the pet, then shelters need to think about whether they can handle the animal safely or whether it’s better off going somewhere else where it can be more safely handled and isolated from others. Ideally, we want to work hard to keep these animals out of shelters. If we can’t, individual shelters need to have a plan. If it’s a healthy animal, it’s easier to say “chuck the animal in a kennel and keep it there until a few days have passed,” at which point the haircoat contamination risk has presumably passed (see above). This doesn’t account for the risk if the animal is truly infected, which is another reason we really need to test more exposed animals to help determine what the risk is.
A test for COVID-19 in animals has been developed and thousands of animals have been negative. So, there’s no concern, right?
This is an issue of poor messaging. As I’ve said before, it’s great to have a test. However, the report from that says thousands of animals have been tested and they’ve all been negative needs to be properly qualified, because none of those animals were from known infected households. Testing animals that have not been exposed to people with COVID-19 tells us nothing about the risk of human-pet contamination or infection, it only tells us that the test doesn’t cross react with normal pet coronaviruses (which is important to know as well). We need samples from pets in households with infected people, but these have been difficult to obtain because of the need for social distancing.
This is just a subset of the important questions I’ve been getting daily. I’ll pause because Maureen will already say “it’s way too long!” (She’s probably right). More questions, and hopefully some answers, in future posts.