A strain of the coronavirus spreading through Hong Kong has mutated to become 30 per cent more infectious than at the start of the outbreak, a top health expert has warned.
Professor Gabriel Leung, dean of the University of Hong Kong’s medical school, said that DNA mutation — first highlighted last month by researchers at the Scripps Research Institute in Florida — meant that each infected person could transmit the coronavirus to four others.
He claimed that another local study had confirmed the trend. The number of people expected to be infected by each case in the city increased in March from two-and-a-half to three, and had now risen to four.
Professor Leung's warning came as Hong Kong faces a potential third wave of coronavirus infections, following a recent spike in cases in the financial hub.
Local officials recorded 52 new cases of Covid-19 on Monday, including 41 that were locally transmitted. Since late January, the city has reported more than 1,500 cases and seven deaths.
Health experts in the territory have warned the recent rise in cases represents the most serious outbreak since the first Covid-19 infection was recorded there on January 22.
Professor Leung, for his part, said he believed there were at least 50 to 60 hidden cases in the community and highlighted Kowloon East and Sha Tin as two local areas most at risk of an outbreak.
“This is the start of a sustained massive local outbreak the likes of which we have never seen before,” the South China Morning Post quoted Professor Leung as saying on a local radio programme on Sunday.
He added: “Hong Kong is currently facing a real and continuous local outbreak.
"The situation has gone back to almost the same level when we had not placed any surveillance measures on the disease at all."
In response to the rise in cases, Hong Kong Chief Executive Carrie Lam said on Monday that the territory would reimpose stricter restrictions on public gatherings from Wednesday onwards.
The government will reduce the number of people allowed to meet from 50 to fourt, a measure last seen during a second wave in March.
Some establishments, such as gyms and gaming centres, will have to shut down for a week, while restaurants will only be allowed to give out takeaway after 6pm. Schools have also been shut.