What causes COVID-19?
Coronaviruses (CoV) are a family of RNA (ribonucleic acid) viruses. They are called coronaviruses because the virus particle exhibits a characteristic ‘corona’ (crown) of spike proteins around its lipid envelope. CoV infections are common in animals and humans. Some strains of CoV are zoonotic, meaning they can be transmitted between animals and humans, but many strains are not zoonotic.
In humans, CoV can cause illness ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (caused by MERS-CoV), and Severe Acute Respiratory Syndrome (caused by SARS-CoV). Detailed investigations have demonstrated that SARS-CoV was transmitted from civets to humans, and MERS-CoV from dromedary camels to humans.
In December 2019, human cases of pneumonia of unknown origin were reported in Wuhan City, Hubei Province of China (People’s Rep. of). A new CoV was identified as the causative agent by Chinese Authorities. Since then, human cases have been reported by the vast majority of countries around the world and the COVID-19 event has been declared by the World Health Organization (WHO) to be a pandemic. For up to date information please consult the WHO website.
The CoV which causes COVID-19 has been named as SARS-CoV-2 by the International Committee on Taxonomy of Viruses (ICTV); this is the scientific name. The virus may also be referred to as “the COVID-19 virus” or “the virus responsible for COVID-19”. COVID19 refers to the disease caused by the virus.
Are animals responsible for COVID-19 in people?
The predominant route of transmission of COVID-19 is from human to human.
Current evidence suggests that the COVID-19 virus emerged from an animal source. Investigations are underway to find that source (including species involved) and establish the potential role of an animal reservoir in this disease. However, to date, there is not enough scientific evidence to identify the source or to explain the original route of transmission from an animal source to humans.
Genetic sequence data reveals that the COVID-19 virus is a close relative of other CoV found circulating in Rhinolophus bat (Horseshoe Bat) populations. There is the possibility that transmission to humans involved an intermediate host.
Priorities for research to investigate the animal source were discussed by the OIE informal advisory group on COVID-19, now the OIE ad hoc Group on COVID-19 and the human-animal Interface, and were presented at the WHO Global Research and Innovation Forum (11-12 February 2020) by the President of the OIE Wildlife Working Group. For more information on the OIE ad hoc Group on COVID-19 and the human-animal Interface and the WHO R and D roadmap please see the links under ‘more information’ at the bottom of this page.
Can humans transmit COVID-19 virus to animals?
Now that COVID-19 virus infections are widely distributed in the human population there is a possibility for some animals to become infected through close contact with infected humans.
Several dogs and cats have tested positive to COVID-19 virus following close contact with infected humans. Further information reported to the OIE can be found below in the ‘more information’ section.
Studies are underway to better understand the susceptibility of different animal species to the COVID-19 virus and to assess infection dynamics in susceptible animal species.
Currently, there is no evidence to suggest that animals infected by humans are playing a role in the spread of COVID-19. Human outbreaks are driven by person to person contact.
What do we know about COVID-19 virus and companion animals?
The current spread of COVID-19 is a result of human to human transmission. To date, there is no evidence that companion animals have spread the disease. Therefore, there is no justification in taking measures against companion animals which may compromise their welfare.
Some examples of animal infections have been reported to the OIE. Further details on these events can be found in the ‘more information’ section. So far, these appear to be isolated cases, and there is no evidence that dogs or cats are playing a role in the spread of this human disease. Further studies are underway to understand if and how different animals could be affected by COVID-19 virus. The OIE will continue to provide updates as new information becomes available.
What precautionary measures should be taken when companion or other animals have close contact with humans sick or suspected with COVID-19?
Currently, there is no evidence that companion animals are playing a significant epidemiological role in this human disease. However, because animals and people can sometimes share diseases (known as zoonotic diseases), it is still recommended that people who are sick with COVID-19 limit contact with companion and other animals until more information is known about the virus..
When handling and caring for animals, basic hygiene measures should always be implemented. This includes hand washing before and after being around or handling animals, their food, or supplies, as well as avoiding kissing, licking or sharing food.
When possible, people who are sick or under medical attention for COVID-19 should avoid close contact with their pets and have another member of their household care for their animals. If they must look after their pet, they should maintain good hygiene practices and wear a face mask if possible. Animals belonging to owners infected with COVID-19 should be kept indoors as much as possible and contact with those pets should be avoided as much as possible.