SARS-CoV-2 (COVID-19): Fomites, Pets, & Transmission

Coronaviruses are enveloped viruses that typically cause respiratory and enteric disease in humans and animals,¹ notably camels, bats, masked palm civets, mice, swine, cattle, horses, chickens, turkeys, dogs, and cats.^2-4 Five coronaviruses are known to circulate in humans: four that cause the common cold, and Middle East respiratory syndrome coronavirus (MERS-CoV), which appeared in Saudi Arabia in 2012.¹ A sixth coronavirus, severe acute respiratory syndrome coronavirus (SARS-CoV-1), emerged in 2002 from China and has not been seen since 2003. A seventh severe acute respiratory syndrome coronavirus (SARS-CoV-2), which causes coronavirus disease (COVID-19), emerged in Wuhan, China, in late 2019 with some exposures linked to the Huanan Seafood Wholesale Market; it is currently circulating at pandemic levels.⁵ Evidence suggests that bats serve as the ultimate reservoir for at least two of the human common-cold associated coronaviruses as well as for MERS-CoV, SARS-CoV-1, and SARS-CoV-2, which infect humans through intermediate animal hosts.^1,6-8

SARS-CoV-2 is transmitted person-to-person via droplets generated from talking, coughing, and sneezing that fall off after approximately six feet and can also be transmitted via fomites (ie, contaminated surfaces and objects).^9,10 There is some evidence that aerosol transmission may be possible.^11-13

SARS-CoV-2 can survive on some surfaces to a limited extent.^11,13 One experimental study examined the survival of SARS-CoV-2 on plastic, stainless steel, copper, and cardboard.¹¹ No viable virus was detected on copper after 4 hours or on cardboard after 24 hours, but virus was viable up to 72 hours on plastic and stainless steel. SARS-CoV-2 genetic material was also detected on environmental surfaces in Huanan Seafood Wholesale Market in China.^6,9,14 Studies of other human coronaviruses have demonstrated survival of up to 9 days on certain surface types, with length of persistence correlated to inoculum dose and ambient temperatures.¹⁵

There is no evidence that domestic animals, or any animal within the United States, can serve as a source for human infection with SARS-CoV-2.^16-19 Although dogs and cats have tested positive for SARS-CoV-2 on PCR and/or serology, there is no evidence that dogs develop clinical signs and limited evidence that cats do.^20-25 There are concerns that companion animals could serve as fomites for transmission of SARS-CoV-2, particularly if the pet belongs to someone ill with COVID-19. 

Although pet skin and fur are recognized sources for human infection for some parasites and microorganisms, there is no evidence that pets can serve as fomites for SARS-CoV-2.^16,26-29 There is also no evidence that inanimate objects associated with pets such as collars, leashes, food or water dishes, can be fomites for SARS-CoV-2. Information and risk messaging regarding pet-to-human transmission may change as more information is collected.