Potential zoonotic sources of SARS-CoV-2 infections

Transbound Emerg Dis. 2021 Jul;68(4):1824-1834. doi: 10.1111/tbed.13872. Epub 2020 Oct 23.

Abstract

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causing coronavirus disease-2019 (COVID-19) likely has evolutionary origins in other animals than humans based on genetically related viruses existing in rhinolophid bats and pangolins. Similar to other animal coronaviruses, SARS-CoV-2 contains a functional furin cleavage site in its spike protein, which may broaden the SARS-CoV-2 host range and affect pathogenesis. Whether ongoing zoonotic infections are possible in addition to efficient human-to-human transmission remains unclear. In contrast, human-to-animal transmission can occur based on evidence provided from natural and experimental settings. Carnivores, including domestic cats, ferrets and minks, appear to be particularly susceptible to SARS-CoV-2 in contrast to poultry and other animals reared as livestock such as cattle and swine. Epidemiologic evidence supported by genomic sequencing corroborated mink-to-human transmission events in farm settings. Airborne transmission of SARS-CoV-2 between experimentally infected cats additionally substantiates the possibility of cat-to-human transmission. To evaluate the COVID-19 risk represented by domestic and farmed carnivores, experimental assessments should include surveillance and health assessment of domestic and farmed carnivores, characterization of the immune interplay between SARS-CoV-2 and carnivore coronaviruses, determination of the SARS-CoV-2 host range beyond carnivores and identification of human risk groups such as veterinarians and farm workers. Strategies to mitigate the risk of zoonotic SARS-CoV-2 infections may have to be developed in a One Health framework and non-pharmaceutical interventions may have to consider free-roaming animals and the animal farming industry.

Keywords: COVID-19; SARS-CoV-2; carnivore; coronavirus; domestic animal; farmed animal.

Publication types

  • Review

MeSH terms

  • Animals
  • COVID-19* / veterinary
  • Cattle
  • Cattle Diseases* / virology
  • Ferrets
  • Humans
  • Macaca mulatta
  • Phylogeny
  • Rabbits
  • SARS-CoV-2
  • Seroepidemiologic Studies
  • Swine
  • Swine Diseases* / virology