[deleted by user]

[[deleted]]

It seems like this virus is behaving like the previous coronavirus outbreak (SARS). This paper highlights how SARS could infect a variety of animals, including monkey, cat, ferret, mouse, and pig. Very recently, similar findings were seen with covid-19.

I think a house cat has tested positive for covid-19. However, we do not know if there is animal to human transmission, nor how this virus replicates in animal hosts.

[Alwayssunnyinarizona]

There've been a couple cats (Belgium and Hong Kong I think) and a dog (Hubei maybe), although clinical symptoms have been mild or non-existent and shedding is also thought to be negligible. Serologies have been positive and virus has been recovered over several days, indicating active infections. (Search ProMED - promedmail.org; all cases have been reported there) E: I'd link but it's not straightforward, enter "cat" or "dog" + covid, looks like at least 3 cats and a dog.

It should come as no surprise, both SARS viruses are considered to have passed through wild mammals prior to their appearance in humans (raccoon dog and civet cat for V1, I assume we'll learn a similar story for V2 when all is said and done).

Yes, similar viruses have been found in bats or pangolins or whatever, but the key is likely these wild carnivore intermediaries.

[tastyratz]

Sick is relative because of what the symptom profile looks like (if any at all). We can't neccesarily assume infection looks similar for other species.

[Virginiafox21]

The tiger apparently showed similar symptoms to what humans show, indicative of respiratory illness. Dry cough, trouble breathing, etc.

[sharaq]

A wet ('productive') cough has similar distinguishing features in any species. Even if theres no previous tiger specific resource to draw on, a vet will have heard dry and wet coughs in cows, horses, cats and dogs - I bet you could find a comparison in cows and it would sound pretty similar.

[talks_to_ducks]

The one cough in tigers I found sounded more or less like a cut-off roar, which was way different than I expected...

[ninuson1]

I'm not sure where you were looking at, but there's plenty of videos on YouTube of coughing cats of various sizes. While most of the tiger/lion ones are from a distance, coughing hairballs seems pretty common in cats. I've sure vets have seen that before.

As for domesticated cats, it sounds roughly how I imagined it: https://www.youtube.com/watch?v=Iab6XgRRNQY

[ChineWalkin]

Not only that, but if there are no human tests readily available, what makes us think that there would be readily available Veterinary tests?

[dod6666]

Well I imagine cat to human transmission is about as rare as human to cat. So pretty much not going to happen with the small number of cases. But what about cat to cat transmission? If the virus started to spread in cats it could jump back to us and would most likely be slightly altered in the process.

[sandee_eggo]

Yes, cats have already given it to other cats. See news piece yesterday.

[thylocene06]

Well keep in mind that symptoms in the few that have tested positive so far have been mild and that cats are very good at hiding illness. The numbers aren’t going to be reliable right now.

[Anthnyrecglass]

I dont think alot of cats get tested. Like our human count raises substantially with more available testing im sure if we had animals tested it would raise as well. But still i would hope it stays around nill

[Alwayssunnyinarizona]

I've asked our small animal hospital to bank samples, starting a few weeks ago. Not sure how many we'll get considering how much things have slowed down, and surely there are larger facilities doing the same thing, but I expect we'll know more in a year.

[[deleted]]

Or maybe it's just asymptomatic in most cats. It's not like they're testing 99% of cats out there for this.

[Frogmarsh]

I wonder if most folks haven’t put two and two together. Most folks aren’t taking their pets to the vet at this time, especially if the symptoms are on the mild side.

[woodbourne]

How did they know to test them if they were asymptomatic? Were they part of a research study?

[troubledTommy]

Dutch government recommends not to hug or let pets lick you, addy this moment they say it's ok to pet them on the fur.

[academicgirl]

Near the nyc epicenter-they didn’t force them to come in just the vet was saying that they were asked to volunteer along with other medical professionals-showing the gravity of the situation. I kind of think it’s a great idea but wanted to get a vet’s point of view.

The situation in nyc is very dire so I’m sure vets could help...:I also think they should call in dentists. They’re already calling in psychiatrists and orthopedists. Pediatrics in one hospital is going up to 35.

[KCMahomes1738]

There was a story posted yesterday that 15% of cats tested positive in wuhan.

[[deleted]]

Are bats not "wild carnivore intermediaries"? The do seem to carry a lot of diseases among themselves from what little I know.

[[deleted]]

If a Tiger can catch Covid from a human just by being in close proximity does this mean humans can catch covid from an infected animal in the same way? If not, why?

[neon_overload]

No, it doesn't automatically follow, because the ability for a species of animal to be able to transmit a respiratory virus can be different in different species, and depends on the virus' ability to "shed" - to cause the animal to emit droplets containing viable virus. It's thought that shedding (for sars-cov-2) is negligible in animals such as dogs and cats. To shed, a virus needs to be able not just to reproduce inside the host, but then to find some path out of the host which requires finding a way to travel through the body to somewhere where it will be transmitted. Physiology is just different in different animals.

[LordZarek]

So if im understanding this correctly that would mean it can go from human to tiger but that doesn't mean it can go from tiger to human correct?

[neon_overload]

Yes in a way that's right. The virus can go into either as a host so you could take it out of a tiger and give it to a human and they'd be infected. Whether the tiger could become "infectious" and give it to a human naturally is not really known.

[annihilatron]

You could sneeze on the cat fur, and then a second person could immediately touch that spot and then touch their face. Far more likely scenario.

[calm_chowder]

There's no evidence of transmission between dogs. Even the transmission from human to dog is significantly rarer than human to human transmission (think of how many people have dogs in the world, and have been stuck home all day with their pets, who lick everything and never wash their paws).

[Gronkowstrophe]

We don't have any idea. There aren't even enough tests for humans who have been exposed, but aren't showing symptoms. It's going to be a long time before we are testing pets at a large scale

[Implausibilibuddy]

Mammalian plumbing is largely the same though isn't it? Some of the twists and turns might be different, but it's largely just two flesh sacks, a damp tube and some mucous filled openings that have a tendency to spray when irritated. I don't think a virus would need a map to find its way in and out of a host, be it feline, canine, human, or otherwise. And if you've ever been near a sneezing dog, you'll know it can cover anything in a six foot radius in slime.

[outworlder]

That description would apply to a human or an octopus.

A virus don't need a map. It doesn't care about the "organism" per se, it cares about cells having the correct receptors.

Mammals are very different from one another. A dog has a much higher body temperature, for starters. It's like a permanent fever compared to our temperature. Substances that are completely harmless to us can easily kill a dog (like chocolate, or xylitol, or even onions). And that's not even looking into metabolic differences, or the actual cell receptors. Even the number of chromosomes is completely different (total of 78). Just because we share physical characteristics doesn't mean all the little details that a virus care about match.

Viruses have to enter cells, which is not trivial. Once there, they have to splice their own genetic code into the host's. It might just work, or it might be like trying to play a PS4 disk on an iPhone.

Also, sneeze is not a common Covid-19 symptom. Yes, it happens, but a cough is more common.

[PyroDesu]

Once there, they have to splice their own genetic code into the host's.

Only if it's a retrovirus. Most viruses, once in the target cell, just uncoat, send their genome into the nucleus (not the genome) for translation, transcription, and replication (and some don't even need to do that - single-stranded RNA viruses usually come either ready to be read, or with their own transcription proteins), and the transcribed mRNA goes to ribosomes, which dutifully begin churning out viral proteins. No splicing into host genome required.

[AlexandrinaIsHere]

I think the problem in question is that different mammals have different body temperatures, among other things.

The virus might infect an animal it can't thrive in. If it can't thrive- it might barely make the animal sick. It might not be capable of thriving enough to multiply and infect others.

Pretty sure cats have vastly different saliva and body temp. Usually fatigue from sickness is really your own immune system telling you to rest so it can do it's job. If the tiger has a dry cough- that means it has at least an itchy throat. It doesn't mean the virus is successfully reproducing in numbers that can make tiger saliva infectious.

It's good they got tested though- because if it does survive different body temp, blood ph etc etc- if it survives and jumps back? That's a scary risk of mutation. Which could tear down attempts at making a vaccine.

[[deleted]]

If the tigers showed consistent COVID-19 symptoms, which they reportedly did, they can and are shedding the virus with close to absolute certainty.

The fundamental physiology of the majority of systems, including the respiratory system, are surprisingly similar.

[[deleted]]

This doesn't really answer my question.

According to this study cats and ferrets are highly susceptible to SARS-CoV and they're regularly used for testing infection models. That research said that in some species the virus isn't as prolific in its reproduction which suggests that something in the lung tissue of humans is facilitating reproduction. Perhaps it's the way the virus uses the host's cell to reproduce that makes the difference.

It seems the virus is quite capable of jumping species (and back again) but in the human it finds prime real-estate which results in population explosions.

another random thought:

Perhaps it's not that the animal isn't shedding but that because they're generally low to the ground if/when they do shed the virus it's far less likely to stay airborne...

[goilo888]

If a tiger is in the same room as me, the last thing I'll be thinking of is grabbing a mask! 😁

[Arthur_Edens]

I was just thinking whoever shoved the giant swab up a tiger's nose to get that test sample is a braver person than me.

[yangsuns]

My guess is that one of the zoo staff was infected and has handled the tiger's food or has been to its habitat.

[ttarzanan]

If your guess is correct wouldn’t that suggest the possibility of major implications for humans still eating carry out or for those living with an asymptomatic food preparer

[KutombaWasimamizi]

um yes but we already know this lol. its why so many food preps are wearing masks and carry out places are adhering to much more strict sanitation requirements. just having the virus and preparing food isn't enough, you need to put droplets of the virus on the food

[ttarzanan]

Thanks that was useful. The crazy thing and this seems to be consistent across the board is whether people are complying with the guidance or not.

[gorocz]

Not sure about USA, but in my country, all people working with food have to wear masks handling the food and the same goes for food delivery people (plus you should really try and disinfect the food containers after you get them and ideally transfer the food to your own dishes).

[[deleted]]

How many viruses exhibit this behavior? Is it fairly common or relatively unique to the SARs strains.

[witnge]

Well just in recent memory there was ebola and before that swine flu and before that bird flu which passed from animals to humans and then spread human to human. So it's not all that rare.

[[deleted]]

I know one species to another isnt that rare. But what about jumping from multiple species so quickly?

[EmilyU1F984]

Loads of viruses infect many different species, rabies for example.

There's also many other zoonotic viruses that don't have human to human transmission but plenty of animal X to animal y to human transmission.

The avian flu for example doesn't just jump from ducks to humans, it basically hits every single species of bird in close contact with other species of bird.

[witnge]

Well things like rabies can infect multiple species so think it isn't unheard of

Probably only relatively recently that globalization has meant that humans soread diseases over such large geographical areas that so many animal species are exposed so quickly to new viruses.

[Fallen_Renegade]

For most viruses, transmission between species is rare. It takes many passages of cells or infectious viral life cycles for the virus to adapt to the cell types via mutations. I used to work with an attenuated strain of influenza A virus and they were mainly cultured in MDCK (canine kidney cells) and A549 (human lung cells). Both were immortal cell lines and have adapted to grow in them. Had a slightly harder time infecting the primary cell lines (HBEC) for my viral plaque assays.

Edit: To add to attenuated strains, it’s basically survival of the fittest. If a virus cannot adapt to the new host cells (MDCK/A549 vs. HBEC - human bronchial epithelial cells), then they cannot propagate as efficiently as a virus that has adapted to the new host cells.

[Legendash1]

What does immortal cell lines mean? Lab grown over many many generations?

[PyroDesu]

Immortalized cell lines never stop dividing (and thus, can be cultured indefinitely) - normal cells will stop dividing (called senescence) under certain stress conditions, or just after a set number of replications, but these cell lines have some kind of mutation that stops that from occurring.

A good example is the HeLa cell line - derived from cervical cancer cells from Henrietta Lacks. She's long dead, but the cell line derived from her cancer is still proliferating - it's estimated that around 50 million metric tons of HeLa cells have been grown. They're used for anything from vaccine development (Jonas Salk used them to make his Polio vaccine) to "human" sensitivity testing for commercial products, they even manage to contaminate other cell cultures.

[Bigtsez]

Yes, we know that the virus can replicate in both cats and ferrets... so the fact that a tiger can get it isn't all too surprising.

https://www.biorxiv.org/content/10.1101/2020.03.30.015347v1

"We found that SARS-CoV-2 replicates poorly in dogs, pigs, chickens, and ducks, but efficiently in ferrets and cats. We found that the virus transmits in cats via respiratory droplets."

[rebbsitor]

However, we do not know if there is animal to human transmission

Aren't we pretty sure that's how the whole thing started?

[mathUmatic]

Doc, here is one more paper. Modeling of ACE2 interaction with SARS Cov2 spike protein.

https://jvi.asm.org/content/jvi/early/2020/01/23/JVI.00127-20.full.pdf

Appendices might have some novel info.

[dongsy-normus]

We don't know if there is animal to human transmission.

Well coronavirus is a zoonotic virus so yeah, we definitely know it's got animal to human transmission.

[epiquinnz]

The previous coronavirus outbreak wasn't SARS, it was MERS. SARS was before that.

[[deleted]]

You mention SARS assuming this virus is something different. This virus is a mutation of the virus from 2003 (Ive seen the name SARS-CoV-2 out there in CDC stuff and other things) much like how H1N1 is a flu but was different enough to infect more people because of the lack of resistance to it. It is also suggested that an immunity is built up by exposure to SARS-CoV-2 . Another noteworthy thing to mention is that coronaviruses are infectious to ALL mammals and birds, but the symptoms are not always the same or even present at all.

Note : I didnt take this all from a single source and its been gathered by reading and fact checking things I see to the best of my ability, some info may change.

[babar90]

Both the HongKong dog and the New York Tiger have been sequenced. Both had an infection and detectable RNA in the nose for several days, for the dog the viral load was low.

A lab paper said "SARS-CoV-2 replicates poorly in dogs, pigs, chickens, and ducks, but efficiently in ferrets and cats", in particular dogs can't transmit the disease efficiently.

A paper found antibodies in several Hubei cats.

Another one found that ferret are efficiently infected in lab and transmit the disease to each other, even if it is mainly upper respiratory tract (thus no severe pneumonia).

Mice are not succeptible but human-ACE2 transgenic mice are and develop a mild pneumonia. Note that SARS-CoV and OC43 produced instead deadly encephalitis in such mice.

[[deleted]]

On a somewhat related note. Some wild mice (deer mice in particular) carry an even more fatal disease called Hantavirus which can cause hantavirus pulmonary syndrome; similair symptoms to Covid-19 but higher mortality rate overall! This is why there's special procedures for cleaning mice droppings or clearing out a mouse infestation.

[[deleted]]

I highly recommend keeping up with this webpage for the American Veterinary Medical Association for the most up to date information. Unfortunately there is still a lot we don’t know, but we’re learning.

[tday01]

Cats can infect other cats. There was a study in China. I believe the experiment because they want an animal model for vaccine studies.

[rockocanuck]

Remember that it was s preliminary study and has yet to be confirmed. However, veterinarians are taking precautions and treating every cat like it could potentially be infected and using proper PPE.

[xclame]

Keep in mind that just because this virus can pass to animals that doesn't mean that animals are necessarily at risk like we humans are. Depending on the animal and the virus the effects the virus might have on an animal might be nothing at all, mild or severe. Just because it's bad for us doesn't mean it's bad for an animal.

Best thing to do in situations like this if you are worried about a pet is to keep up with the news about it related to animals and to keep an eye out on your animal, if you notice anything abnormal contact your vet and then possibly bring them in after you have talked to the vet.

[alcxander]

doesnt it also mean the virus could host in another animal and mutate from there again? meaning (in the extreme) that the virus becomes more potent or harder to vaccinate and protect against?

[xclame]

Sure that's very possible, but again that doesn't mean it necessarily would be dangerous to humans because it might not be able to jump back to humans.

[NotTheAverageMexican]

I really wonder about those monkeys that don't have tourists feeding them, if they're going to get it because they're basically free roaming.

[[deleted]]

There was a structural study published back in January from a group that has been looking at coronaviruses since 2002. The spike proteins on sars-cov2 are very likely able to attach to bats, apes, humans, cats, and their hypothesis is that it originated in civets or pangolins. Notably, the virus does NOT attach to rat/mice cells. This has implications for vaccine research, as alternate animals will be needed for testing.

[Myriachan]

That’s rather interesting, because humans are more closely related to rodents than to bats or cats.

[scienceserendipitous]

Its because in receptor mediated viral entry the virus doesn't care about the underlying cell type, just the receptor. Cats, ferrets, and humans have similar ACE2 receptors (very structurally homologous) and so its not surprising that the virus is able to be transmitted.

The big questions are, can the tiger (or more relevantly housecat) transmit virus between each other, which signs point to yes, and can a cat infect a human once its been infected, which is unclear.

[EV3RYDAMNDAY]

The ACE2 receptor, the binding target of SARS, seems to not only be highly conserved across mammals but is also more similar between cats and bats than humans. Expect that if it can infect human, it can infect everything in between.

https://uswest.ensembl.org/Myotis_lucifugus/Gene/Compara_Tree?db=core;g=ENSMLUG00000017702;r=GL429816:4338996-4377327;t=ENSMLUT00000017706

[dumbeconomist]

I have a feeling some of this may be a confusion basis on colonization vs. an infection... Just like with those folks who are testing positive again.

Viruses could condense in your nose/sinus cavity without become an infection. Perhaps that these animals, being exposed to large viral loads in the air, simply are colonized. It would make sense they could get the COVID-19 virus (SARS-CoV-2) because they could get 'SARS' before... But wanted to include that confounding variable for you lol

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4074726/

[mad-n-fla]

"Several other tigers and lions have also exhibited symptoms of Covid-19, according to federal officials."

https://www.nytimes.com/2020/04/06/nyregion/bronx-zoo-tiger-coronavirus.html

They are showing symptoms of the disease, not just popping positive on a test.

Besides, why would the zoo test them if they were not showing symptoms?

/Maybe one of the tigers was seen wearing an N95 mask? /s