Widespread exposure to SARS-CoV-2 in wildlife communities

Area of Science:

• Veterinary Medicine
• Wildlife Ecology
• Infectious Diseases

Background:

• Human infections with SARS-CoV-2 have resulted in animal transmissions.
• While SARS-CoV-2 can infect many animal species, documented cases are mainly in captive animals and white-tailed deer.
• The complete scope of SARS-CoV-2 exposure in wildlife and factors influencing transmission risk are not fully understood.

Purpose of the Study:

• To investigate the prevalence of SARS-CoV-2 in diverse wildlife populations.
• To assess the impact of urbanization and human activity on wildlife seropositivity.
• To identify wildlife species exposed to SARS-CoV-2 and analyze transmission dynamics.

Main Methods:

• Collected samples from 23 wildlife species across Virginia and Washington, D.C. (May 2022-September 2023).
• Tested for SARS-CoV-2 RNA and antibodies (seropositivity).
• Analyzed the correlation between human activity levels and seroprevalence.
• Performed genomic sequencing on positive samples to identify viral lineages.

Main Results:

• Detected SARS-CoV-2 RNA in six species: deer mouse, Virginia opossum, raccoon, groundhog, Eastern cottontail, and Eastern red bat.
• Wildlife populations in high human-use areas exhibited three times higher seroprevalence compared to low-use areas.
• Genomic sequencing revealed seven Pango lineages of the Omicron variant from nine individuals across six species.
• Identified at least seven recent human-to-animal SARS-CoV-2 transmission events.

Conclusions:

• SARS-CoV-2 exposure is widespread among wildlife communities.
• Areas with significant human activity act as hotspots for human-to-wildlife SARS-CoV-2 transmission.
• Continued surveillance of wildlife for SARS-CoV-2 is crucial, especially in human-dominated landscapes.