Are Animals a Neglected Transmission Route of SARS-CoV-2?

Abstract

Little information on the SARS-CoV-2 virus in animals is available to date. Whereas no one husbandry animal case has been reported to date, which would have significant implications in food safety, companion animals play a role in COVID-19 epidemiology that opens up new questions. There is evidence that SARS-CoV-2 can infect felines, dogs and minks, and there is evidence of human-to-animal infection. Likewise, the S protein nucleotide sequence of the SARS-CoV-2 virus isolated in domestic animals and humans is identical, and the replication of the SARS-CoV-2 in cats is efficient. Besides, the epidemiological evidence for this current pandemic indicates that the spillover to humans was associated with close contact between man and exotic animals, very probably in Chinese wet markets, thus there is a growing general consensus that the exotic animal markets, should be strictly regulated. The examination of these findings and the particular role of animals in COVID-19 should be carefully analyzed in order to establish preparation and containment measures. Animal management and epidemiological surveillance must be also considered for COVID-19 control, and it can open up new questions regarding COVID-19 epidemiology and the role that animals play in it.

Keywords: COVID-19; Food Safety; One Health; SARS-CoV-2; epidemiology; neglected route.

Figure 1

Phylogenetic analysis of amino acid sequences of the angiotensin-converting enzyme 2 (ACE2) receptor in different animals and humans. The ACE2 orthologous amino acid sequences were downloaded from NCBI (https://www.ncbi.nlm.nih.gov/gene/59272/ortholog/?scope=33554) and aligned with COBALT (https://www.ncbi.nlm.nih.gov/tools/cobalt/re_cobalt.cgi). The tree was generated using a maximum likelihood estimate with FastTree, under a JTT model. The graphic representation was made with the ggtree package in R, and each color in the multiple sequence aligment (msa) corresponds to an amino acid.

Figure 2

Nucleotide comparison of SARS-CoV2 spike protein from viruses isolated from animals (pangolin, bat, cat, tiger, mink, and dog) and the reference human virus isolated in Wuhan. In green, the consensus with the human SARS-CoV-2 virus sequence. Red box signs, the 6 binding sites of the receptor-binding domain (RBD) of SARS-CoV-2 to ACE receptor.