Severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) is a
strain of coronavirus that causes COVID-19, the respiratory illness
responsible for the COVID-19 pandemic. The virus previously had the
provisional name 2019 novel coronavirus (2019-nCoV), and has also been
called human coronavirus 2019 (HCoV-19 or hCoV-19). First
identified in the city of Wuhan, Hubei, China, the World Health Organization
designated the outbreak a public health emergency of international concern
from January 30, 2020, to May 5, 2023. SARS‑CoV‑2 is a positive-sense single-
stranded RNA virus that is contagious in humans.