A novel coronavirus, referred to as SARS-Cov2 (Severe Acute Respiratory Syndrome Coronavirus 2) was first identified in Wuhan, Hubei Province in China in December 2019. SARS-Cov2 infection causes Coronavirus disease 2019 (COVID-19).

Coronaviruses are a group of related viruses that cause disease in several animal species. In humans, coronaviruses cause respiratory tract infections that are typically mild, such as some cases of the common cold. Rarer forms, such as SARS-Cov1 (which was first identified in 2003) and the virus that causes Middle East Respiratory Syndrome (MERS, identified in 2012) are more lethal.

Exactly where COVID-19 sits on the spectrum of mild to lethal is dependent on additional data being collected and analysed. Present estimates suggest that it is more lethal than the coronavirus responsible for the common cold but less lethal than those which cause SARS or MERS.