This is an exploratory question.

If a COVID-19 infected person (person is unaware that he is infected) milks the cow for couple of days, is there a possibility of him infecting the cow thereby infecting the milk?

Similarly, if a dog licks the face of COVID-19 infected person, is it possible that the virus may spread through its saliva to another person in the vicinity.

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    Have you googled something? You might want to include a previous research. – I likeThatMeow Mar 31 '20 at 17:00
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    I have not come across any information related to the question. Since there is so much discussion about the spread of COVID-19, I was curious to know if this way of transmission is possible. – Suddhasattwa Ghosh Mar 31 '20 at 17:37

Covid-19 is the result of a zoonotic outbreak from bats to an intermediate ( and unidentified host ) thence to humans. It is thought that bats don't suffer the disease themselves as they carry low levels of virus but the intermediate host modifies the virus, and amplifies it so that it vastly increases the amount of virus that can shed into the environment infecting humans. One possible scenario is that bat coronavirus combined with a fish coronavirus inside the intermediate host. This is based on the observation that the SARS-CoV-2 spike gene shares a 39-base insertion with a type of soldierfish that swims in the South China Sea.

The SARS-CoV-2 infects humans via the ACE2 surface receptor, but this receptor is not only found in humans. Other animals have similar but not exactly the same ACE2 receptors and several dogs and one cat have returned positive swabs for SARS-CoV-2. The cat developed covid-19 symptoms. The first dog died two days after being released back to its owner but that might have been from the stress of quarantine in a 17 year old Pomeranian. Ferrets also have an ACE2 receptor which also binds strongly to the SARS virus so presumably are also at risk. Mice appear to be less at risk.



The Hong Kong Govt is now asking that pets of infected patients must now be quarantined for 14 days.

The CDC gives the following advice (which is out of date based on the above):



We don't have information on cows but presume that they may also be susceptible.

EDIT: Experimental data suggests cats are more susceptible to the virus than dogs

The team, led by virologist Bu Zhigao, infected five domestic cats with SARS-CoV-2 through the nose. When two of the cats were euthanized six days later, the researchers found viral RNA, as well as infectious virus particles, in their upper respiratory tracts.

The other three infected cats were put in cages next to three uninfected felines. The team later detected viral RNA in one of the non-infected cats, which suggests that they contracted the virus from the infected cats through respiratory droplets. All four cats also produced antibodies against SARS-CoV-2. Surveillance for SARS-CoV-2 in cats should be considered as part of efforts to eliminate COVID-19 in humans, the authors note in the preprint, which has not been peer reviewed.

6 April 2020

7 lions and tigers reported infected by a zoo keeper at NY's Bronx zoo. A Malayan Tiger first fell ill.


Dogs, however, were less susceptible to the virus. The researchers infected five young dogs and found that two excreted viral RNA in faeces, but none contained infectious virus.

Similar investigations in pigs, chickens and ducks identified no viral RNA in animals deliberately infected with the virus, or those exposed to the infected animals

Edit 21 May 2020

A paper from April 2020 shows a high affinity for bovidae ACE2 for the COVID-19 binding region which suggests that cows can be easily infected.

In conclusion, we found that Bovidae/Cricetidae ACE2 but not turtle/snake ACE2 could recognize SARS‐CoV‐2 RBD. More attention should be paid to Bovidae and Cricetidae in hunting the potential intermediate host for SARS‐CoV‐2.








SARS‐CoV‐2 spike protein favors ACE2 from Bovidae and Cricetidae https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7228376/

  • Possibly worth calling out ferrets specifically, as they're so similar to humans regarding coronaviruses that they're one of the core animal models; they're known to easily catch the common cold. – chrylis -cautiouslyoptimistic- Apr 1 '20 at 4:37
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    Ok, added ferrets and mice – Graham Chiu Apr 1 '20 at 5:22
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    The Belgian cat case was later on dismissed: all the fluids and dejections of the cat were taken by the COVID-19-infected owner in non-sanitary conditions. The cat was not examined by anyone but her owner. lalibre.be/belgique/societe/… (Sorry, it's in French) – Olivier Grégoire Apr 1 '20 at 11:19
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    Can you respond to the question whether the milk may transmit the disease if we presume that the cow is infected? – Toivo Säwén Apr 1 '20 at 11:33
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    @OlivierGrégoire Experimentally infecting cats show that they appear to pass the disease on to other cats. – Graham Chiu Apr 1 '20 at 22:17

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