[custom_adv] At the end of the lunar new year, millions of Chinese workers who travel across the country to visit family return to manufacturing hubs like Shenzhen, Ningbo and Guangzhou. [custom_adv] The holiday is always disruptive. Every year, activity must be scaled back and production reduced as workers take time off. [custom_adv] But assembly lines can be rebooted as soon as the bullet trains and buses bring them back. [custom_adv] This year has been different. The coronavirus epidemic has already seen the new year, which was due to end on Thursday, extended until this Sunday, and Beijing has advised citizens to avoid travel. [custom_adv] 2019-nCoV joins the four coronaviruses now circulating in people. “I can imagine a scenario where this becomes a fifth endemic human coronavirus,” said Stephen Morse of Columbia University’s Mailman School of Public Health, an epidemiologist and expert on emerging infectious diseases. [custom_adv] “We don’t pay much attention to them because they’re so mundane,” especially compared to seasonal flu. [custom_adv] “We don’t pay much attention to them because they’re so mundane,” especially compared to seasonal flu.