Potential zoonotic sources of SARS‐CoV‐2 infections

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.

SARS-CoV-2 Seroprevalence in Household Domestic Ferrets (Mustela putorius furo)

“…Reports showed that humans can become a source of infection for minks, which has resulted in a disease outbreak [ 12 , 13 ]. Equally, epidemiologic evidence supported by genomic sequencing corroborated mink-to-human transmission events in farms [ 14 ].…”

The Case for S2: The Potential Benefits of the S2 Subunit of the SARS-CoV-2 Spike Protein as an Immunogen in Fighting the COVID-19 Pandemic

“…While many mutations have been discovered, there is focus on the Y453F mutant in the RBD, as a preliminary report shows that this mutation increases the affinity of the RBD for the human ACE2 receptor ( 37 , 38 ). The mink is now a well-known animal reservoir for SARS-CoV-2, and transmission to humans has been demonstrated ( 39 ). While further investigation is needed to determine whether the mutations in this mink outbreak could epidemiologically worsen the COVID-19 pandemic, the principle remains that mutations in the RBD may yield more transmissible variants.…”

Host Diversity and Potential Transmission Pathways of SARS-CoV-2 at the Human-Animal Interface

“…It is hypothesized that a virus-tolerant phenotype in bats has facilitated the co-evolution of bat hosts with viral pathogens [ 148 ]. Molecular epidemiological studies of the origins of CoVs have linked SARS-CoV-like CoVs in bats as the reservoirs to SARS-CoV, MERS-CoV, and endemic HCoV-NL63 and HCoV-229E [ 16 , 149 ]. Recent research suggests that bats are the evolutionary reservoir to SARS-CoV-2 [ 105 , 141 , 150 ].…”