In 2019, the Centers for Disease Control and Prevention (CDC) started monitoring the outbreak of a new coronavirus, SARS-CoV-2, which causes the respiratory illness now known as COVID-19. Authorities first identified the virus in Wuhan, China.
More than 78,191 people have contracted the virus in China. Health authorities have identified many other people with COVID-19 around the world, including in the United States. On January 31, 2020, the virus passed from one person to another in the U.S.
Since then, this strain has been diagnosed in several U.S. residents. The CDC have advised that it is likely to spread to more people. COVID-19 has started causing disruption in at least 25 other countries.