COVID-19 cannot be transmitted by either farm animals or domestic animals
The emergence in China in late 2019 of a new coronavirus disease, COVID-19, and its rapid spread around the world have led researchers and health authorities to take prompt and widespread action to better understand the virus involved and how we can protect ourselves from it.
It soon emerged that this virus, named SARS-CoV-2, is transmitted from person to person. In France, ANSES was asked to review the available scientific knowledge and assess the possibility of COVID-19 being transmitted via domestic animals or contaminated food. ANSES published its report on 11 March 2020. On the basis of the scientific knowledge available at the time, it concluded that there was no evidence that pets or farmed animals played any role in the spread of the disease. Furthermore, there is nothing to suggest that consumption of contaminated food can lead to infection via the digestive tract.
In order to limit the spread of the virus, it is essential to follow the recommendations and mechanisms put in place by the authorities. Find out more:
> The government's web page (in French)
> The Ministry of Health's web page (in French)
No transmission by domestic animals
Because the virus's genetic structure indicates that it probably originated in animals, ANSES was consulted, and set up an Emergency Collective Expert Appraisal Group to examine the potential role of domestic animals and food in virus transmission.
With regard to possible transmission of the virus by livestock and domestic animals, the conclusions of the expert group indicate that:
- the genetic structure of the SARS-CoV-2 virus does indeed suggest that an animal was its initial source. It probably comes from a species of bat, and an intermediate host may or may not have been involved. However, as things stand today and in light of the published information available, the passage of SARS-CoV-2 from humans to another animal species currently seems unlikely ;
- the SARS-CoV-2 virus binds to a specific cellular receptor, which allows it to gain access to cells. Although this receptor has been identified in domestic animal species and appears to be capable of interacting with the human virus – and further studies on this subject are needed – the experts reiterate that the receptor's presence is not a sufficient condition for infection in these animals. This is because the virus uses not only the receptor, but also other cell components that allow it to replicate.
The virus can survive several hours on an animal’s fur. Therefore, to avoid contamination,
- separate the animal from any people who are ill or are presumed to be ill;
- do not allow the animal to lick your face;
- wash your hands before and after petting any animals.
No evidence of possible contamination via the digestive tract
Since contamination of animals by the virus is unlikely, the possibility of direct transmission to humans through food derived from a contaminated animal was ruled out by the experts. Only the hypothesis of contamination of food by a person who is sick, or is an asymptomatic carrier of the SARS-CoV-2 virus, was investigated.
This could occur through respiratory droplets from a contaminated patient. However, the question of the faecal-oral route was also raised, as viral particles have been detected in the faeces of some patients.
After examining the available data, the expert group reached the following conclusions:
- based on the current state of knowledge, transmission of the SARS-CoV-2 virus directly via the digestive tract can be ruled out. Indeed, while the virus has been observed in patients' faeces, it was probably due to circulation of the virus in blood following respiratory infection rather than through the digestive tract. However, the possibility of the respiratory tract becoming infected during chewing cannot be completely ruled out;
- as with other known coronaviruses, this virus is sensitive to cooking temperatures. Heat treatment at 63°C for 4 minutes (temperature used when preparing hot food in mass catering) can therefore reduce contamination of a food product by a factor of 10,000;
- an infected person can contaminate food by preparing or handling it with dirty hands, or via infectious droplets produced when coughing or sneezing. Good hygiene practices, when properly applied, are an effective way to prevent food from being contaminated with the SARS-CoV-2 virus.