SARS-CoV-2 Secondary Spillover: From Doubt to Evidence

Abstract

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the culprit behind the coronavirus disease 2019 (COVID-19) and it is believed that bats may have been the source. SARS-CoV-2 can naturally infect humans and various animal species, including pets, farm animals, zoo animals, and wild animals that might serve as potential reservoirs for the viral transmission to humans. Most infected animals with SARS-CoV-2 are associated with exposure to infected humans; therefore, SARS-CoV-2 is characterized by zoonosis and reverse zoonosis. It is critical to quickly detect and classify variants of concern of SARS-CoV-2 in both domestic and wild animals. In addition, it’s possible that novel variants emerging due to viral mutation, making the infection of incidental animal hosts worrying. Here, we discuss the most recent information on the spreading of SARS-CoV-2 among animals and humans, the importance of genomic research, and active surveillance of these animals that may help us to understand the spread of viruses and the emergence of variants.