Scientists have found that several viruses which belong to the Coronaviridae family can infect a wide range of hosts, including birds, humans, and other mammals. These viruses are single-stranded, positive-sense, RNA viruses whose size ranges between 27-32 kb. They are divided into four categories, namely, alpha, beta, delta, and gamma.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causal agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic, and was first identified in the Wuhan province of China in December 2019. Owing to its high infectivity and mortality rate, the World Health Organization announced COVID-19 to be a pandemic on 11th March 2020.
