SARS-CoV-2 infection and transmission in the North American deer mouse

Widespread circulation of SARS-CoV-2 in humans raises the theoretical risk of reverse zoonosis events with wildlife, reintroductions of SARS-CoV-2 into permissive nondomesticated animals. Here we report that North American deer mice (Peromyscus maniculatus) are susceptible to SARS-CoV-2 infection following intranasal exposure to a human isolate, resulting in viral replication in the upper and lower respiratory tract with little or no signs of disease. Further, shed infectious virus is detectable in nasal washes, oropharyngeal and rectal swabs, and viral RNA is detectable in feces and occasionally urine. We further show that deer mice are capable of transmitting SARS-CoV-2 to naïve deer mice through direct contact. The extent to which these observations may translate to wild deer mouse populations remains unclear, and the risk of reverse zoonosis and/or the potential for the establishment of Peromyscus rodents as a North American reservoir for SARS-CoV-2 remains unknown.
Deer mice are natural hosts for a number of human pathogens. Here, Griffin et al. report that intranasal exposure of the North American deer mouse to SARS-CoV-2 results in virus replication and shedding, despite causing only mild or asymptomatic illness. Additionally, infected deer mice can transmit SARS-CoV-2 to naïve deer mice.