An outbreak of a pneumonia-like illness that started in the city of Wuhan has put health authorities on high alert in China and around the world. The new coronavirus — named 2019-nCoV — is thought to have originated in the food market of the central China metropolis and has since infected more than 4,500 people. Deaths and cases are likely to rise until the outbreak is contained. • China first reported the outbreak on Dec. 30. Most of the deaths have been in Hubei province, where Wuhan is the capital. Chinese authorities have restricted some travel to try and stop the illness’s spread during the Lunar New Year, which started on Jan. 25. China’s financial markets will remain closed until next Monday Feb. 3 after authorities extended the holiday break by three days. • In Wuhan, public transportation and ride-hailing services have been suspended, trains and flights from the city have been stopped and people have been told to leave only for essential reasons. Similar travel restrictions were announced in at least 11 other Chinese cities, impacting more than 40 million people.