Yuen, a leading microbiologist and infectious-diseases expert at the University of Hong Kong, said
many of the21 patients found to be infected in the city had not visited the mainland recently.
He said he was convinced a local outbreak had started, and human-to-human transmission was taking place within the city. Yuen said every measure should be taken to minimise the spread, including further border closures.
Six people in the city have been diagnosed with the coronavirus over the past two days, five of whom had not left the city recently. Of the 21 cases in total, eight were believed to have no travel history relevant to the coronavirus.
“The local transmission chain has begun, and if we do nothing to control it, Hong Kong will become like some mainland city that has suffered lots of cases,” Yuen said.