HONG KONG — The Covid-19 epidemic caused by the coronavirus will not end this year as the contagion has spread worldwide, a leading microbiologist from Hong Kong has said.

Professor Yuen Kwok-yung from the University of Hong Kong, who advised authorities on control measures against the disease, said although the situation in mainland China and Hong Kong might improve in summer, there could be more imported cases from the southern hemisphere in winter.

"We think the epidemic will probably not come to an end," Mr Yuen said on a pre-recorded television interview aired on Sunday (March 8). "There will be what we call reversed imported cases. In the beginning other countries feared us, now we fear them [for bringing in the virus]."

He elaborated further in a reply to the Post later on Sunday that in his view, the epidemic would not end until a cheap and effective antiviral or vaccine became available or the majority of the population had contracted the virus and got natural immunity.

Since late February, Covid-19 infections have jumped in South Korea, Italy and Iran, which are now the three countries with the highest number of cases outside China. On Sunday, it was reported that Italy would quarantine the entire Lombardy region with a population of some 10 million, after recording its biggest surge in daily cases, at 1,247, since the outbreak in the country began on Feb 21.

As of Sunday evening, Hong Kong had 114 confirmed cases and three related deaths.

Mr Yuen also urged people to avoid travelling at least until the end of the year. He pointed to two infections in Hong Kong that were linked to a recent tour group to India. Another woman in her 80s from the same group was also diagnosed with Covid-19 after returning to Vancouver, Canada.

"When the epidemic is serious, avoid travelling to other places unless necessary," Mr Yuen said.

He added that while the global spread of the virus had shifted the focus away from tightening border measures between Hong Kong and mainland China, it was too early to tell if the situation on the mainland would be "under control by April", as suggested by some experts there.

Mr Yuen also said the virus, like most strains, had been mutating, but assured that for now there was no evidence to suggest it had become more deadly or easily transmitted.

The key to fighting epidemics, Mr Yuen reiterated, started with personal hygiene.

"If everyone washes his or her hand, wears a mask all the time and maintains social distancing, the risk of infection will be lowered. It's a matter of compliance," Mr Yuen said.

"We cannot guard against the virus forever, but the longer we delay its spread, the higher the chances of getting a vaccine in time."

In a separate interview also published on Sunday by mainland Chinese online media Caixin, Mr Yuen said his team and other scientists were developing a vaccine. He revealed that tests on mice showed no side effects, and successfully produced antibodies, but further procedures were required.

"I believe it will be one year or 11/2 years until clinical applications," he was quoted as saying. SOUTH CHINA MORNING POST