The receptivity to SARS-CoV-2 is the ability of an animal species to harbor the virus without necessarily developing symptoms. There sensitivity is the ability of the animal species to express clinical signs and/or lesions due to the virus.
The data available to define whether an animal species is receptive or sensitive to the SARS-CoV-2 virus come either from experimental infections or from natural infections observed in the field.
Chicken, turkeys, ducks, cattle and pigs: receptivity and sensitivity to SARS-CoV-2 not established or yet to be confirmed
No experimental infection has yet shown that the chickens, turkeys and ducks were susceptible or susceptible to SARS-CoV-2. Furthermore, no natural infection data has been recorded to date.
Re cattle and pigs, additional studies are necessary to confirm or invalidate their susceptibility to SARS-CoV-2, but published studies show that these animals are not sensitive to it.
Dogs and rabbits: species susceptible to SARS-CoV-2 but whose susceptibility remains to be confirmed
And THE rabbits and the dogs are susceptible to SARS-CoV-2, their sensitivity remains to be confirmed.
Very few dogs have developed clinical signs in natural conditions given the very high levels of exposure to the virus (thousands of people infected with COVID-19 have been in close contact with their dog). Moreover, the tests carried out on contact dogs have not made it possible to demonstrate transmission of the virus between them. Finally, there is currently no scientific data demonstrating transmission of SARS-CoV-2 from dogs to another species.
As for the rabbit, the experimental infections tend to show the presence of lesions due to the virus, but these need to be confirmed.
Cat, ferrets, hamsters, mink…: established receptivity and sensitivity to SARS-CoV-2
Among the best-known animal species:
- THE chats are receptive and sensitive to SARS-CoV-2 with proven intra-species transmission, i.e. between individuals of the same species. On the other hand, to date there is no scientific data demonstrating transmission of SARS-CoV-2 from cats to another species. As with dogs, the occurrence of natural infections in cats with SARS-CoV-2 occurs in a context of high viral pressure, through close contact with their owners affected by COVID-19;
- THE ferrets et hamsters are receptive and susceptible to the SARS-CoV-2 virus, with proven intra-species transmission. However, at this stage there is no scientific data showing transmission of SARS-CoV-2 from these animals to other species, nor of natural infection;
- concerning mink, data from natural infections reported in the Netherlands, Denmark, Spain and the United States show that this species is receptive and susceptible to SARS-CoV-2, with proven intra-species and presumed inter-species transmission . The events that occurred in the Netherlands and more recently in Denmark, are in favor of a transmission and return of the virus from infected mink to humans. The Agency emphasizes that the occurrence of these transmission events from infected mink to humans is likely to be linked to the context of high viral pressure due to a high density of the animal population within these farms;
- THE tigers, lions et puma in captivity in zoos are species receptive and susceptible to SARS-CoV-2.
The receptivity and sensitivity of other lesser-known species such as toupaye or fruit bat were also assessed by ANSES. The results are detailed in the full review.
Domestic and wild animals do not play an active role in the Covid-19 epidemic to date.
To date and in the light of the scientific elements currently available, the Agency confirms that the domestic and wild animals do not play an epidemiological role in the maintenance and spread of SARS-CoV-2. At this stage, this spread is the result of human-to-human transmission by the respiratory route.
However, the susceptibility of certain animal species to SARS-CoV-2 having now been established, the there is a risk of an animal reservoir forming. In this respect, ANSES recommends being particularly vigilant with regard to situations involving contact between humans and receptive species (cats, mink, etc.), in conditions of high animal density, and animal-human promiscuity, particularly in closed or confined environments. Thus, during any contact with a receptive animal, strict hygiene measures must be applied: wash your hands with soap after touching an animal or after cleaning its litter, avoid close contact on the face, wear a mask in case of manipulation of a receptive animal, etc. THE people with COVID-19 should avoid close contact with animals, without compromising their well-being. When contact cannot be avoided (eg animal care), it is recommended that they wear a mask and wash their hands before and after contact with animals.
Likewise, a vigilance is necessary towards receptive wild animals held in captivity (minks, lions, pumas, etc.). In a context of high viral pressure, the Agency therefore reiterates the need to implement the adequate security measures in breeding susceptible species to prevent the introduction and spread of the virus.