Equine Review

The arrival of this novel coronavirus and the subsequent pandemic is a public health emergency. In order to understand how the virus infects a patient one needs to understand its genome. This virus is designated severe acute respiratory syndrome coronavirus 2 (SARS)-CoV-2 by the International Committee on Taxonomy of Viruses. This virus is the seventh coronavirus causing human diseases; coronaviruses are proven to cross the species barrier affecting human (zoonosis), and SARS-CoV-2 has been isolated in animals. However, despite all the studies being carried out on this virus the transmission path, the natural host and intermediate adaptive species if any, remain unidentified. The study by Wang and co-workers (2020) demonstrated that SARS-CoV-2 uses the ACE2 receptor to enter human cells (Wang et al. Cell. 2020; doi: 10.1016/j.cell.2020.03.045). This finding has generated some discussion about whether ACE inhibitors and/or angiotensin-receptor blockers could be a potential treatment for COVID-19 or, conversely, worsen the disease. Among the seven coronaviruses discovered, only three of them are shown to use this receptor for cell entry in humans. The structural information of the SARS-CoV-2 obtained in this study should help to identify inter-species transmission route(s) by characterising the interactions of SARS-CoV-2 with receptors of different species.