The novel coronavirus 2019-nCoV is thought to have made the jump to humans in a Wuhan seafood market, where live, wild animals are kept in close proximity with food. This month, the spread of the virus has prompted an unprecendented quarantine in China that has ground rail, bus and airplane travel to a halt. Outside of China, the outbreak has spread to several countries across multiple continents.
You can track its progress through this interactive map created and updated by the Johns Hopkins University Center for Systems Science and Engineering using data provided by the World Health Organization, the Centre for Disease Control and Prevention (CDC) in the U.S., the National Health Commission of the People's Republic of China, and Dingxiangyuan, a social networking site for health care professionals that provides real-time information on cases.
(Note: You can toggle between desktop and mobile versions of the map from the dropdown menu in the upper right-hand corner.)