New York | The panic generated by the new coronavirus, 2019-nCov, which originated in Wuhan, one of China’s largest cities and a major domestic transport hub, reminds many of the fear and uncertainty at the peak of the 2003 SARS crisis.

China’s sharemarket, after rising for months, has reversed itself in recent days, and global markets have followed suit, apparently reflecting concerns about the epidemic’s impact on the Chinese economy and global growth. Are these worries justified?