Coronaviruses and Animals

Coronaviruses are a large family of viruses that have been found in a wide range of animal species, including cats, dogs, cattle, pigs, horses, rodents, camels, ferrets, bats, wild birds, and poultry. The different coronaviruses can cause a variety of illnesses in animals ranging from mild diarrhea or respiratory signs to severe disease and occasionally death.  Nearly all of the coronaviruses that infect animals do not cause illness in humans.

There are only a small number of coronaviruses that can infect humans. Four coronaviruses normally circulate among humans and cause relatively mild illnesses such as the "common cold". Three other coronaviruses discovered within the last 20 years can cause severe and potentially fatal disease in humans. These include Middle East Respiratory Syndrome Coronavirus (MERS-CoV), Severe Acute Respiratory Syndrome Coronavirus 1 (SARS-CoV-1), and Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).

Middle East Respiratory Syndrome Coronavirus (MERS-CoV)

Middle East Respiratory Syndrome Coronavirus is a novel coronavirus first identified in Saudi Arabia in 2012 that causes severe acute respiratory illness and death in humans. This virus also causes respiratory disease in camels. Humans become infected through direct or indirect contact with camels. MERS-CoV is not transmitted easily between humans. This virus is confined mainly to the Arabian Peninsula and has not spread to other parts of the world. The only known cases of MERS-CoV in the U.S. were in people who had returned from travel to Saudi Arabia.

Severe Acute Respiratory Syndrome (SARS) Coronaviruses (CoV)

• SARS-CoV-1

SARS-CoV-1 (or SARS-CoV) is the cause of the human disease Severe Acute Respiratory Syndrome (SARS). This virus is closely related to SARS-CoV-2, which is the virus that causes COVID-19 in humans. SARS symptoms include fever, cough, sore throat, muscle pain, shortness of breath, and pneumonia. SARS-CoV-1 can cause severe disease that requires hospitalization and intensive care. SARS was first reported in China in 2002 and continued to be reported from Asia until May 2004. Most of the cases were in China and Hong Kong, with some cases reported in people returning from travel to these areas. There have been no reports of human infection with SARS-CoV-1 since 2004.

The origin of the SARS-CoV-1 virus is unknown. Genetic analysis showed the virus to be closely related to a coronavirus found in Horseshoe bats native to China. The virus was also found in palm civets — a wild, weasel-like animal native to Asia that is often sold as food at Chinese live animal markets. It is thought that the initial transmission of SARS-CoV-1 to humans was through contact with bats or civets at these markets.

Research studies suggest that dogs are not susceptible or at risk for infection with SARS-CoV-1, but that pigs, cats, and ferrets can become infected with this virus. There have been no reports of cats or ferrets spreading this virus to humans.

• SARS-CoV-2 (this is the virus that causes human COVID-19 — click for more details)