Hong Kong is experiencing a renewed rise in Covid-19 cases, driven by evolving virus strains and declining population immunity, according to an infectious diseases expert.

Speaking on a Commercial Radio programme on Saturday, Lau Yu-lung, chairman of the scientific committee on vaccine preventable diseases at the Centre for Health Protection, said that while the current toll of severe cases and fatalities remains below levels seen during last year’s peak, public complacency should not set in.

"The transmission rate has been relatively low over the past six months," he said.

"During this time, most people in Hong Kong have not been infected with the virus, resulting in lower levels of antibodies in their blood.

"With the emergence of a variant known as KP.3, a certain number of residents became infected, leading to more extensive transmission of the virus once it entered the community."

Lau stressed that vaccines continue to offer robust protection against severe outcomes, urging high-risk groups – including the elderly and immunocompromised – to stay up to date in their vaccinations.

For his part, Dr Mike Kwan, president of the Asian Society for Pediatric Infectious Diseases, encouraged children to get their vaccinations if they have not yet completed their primary series.

He warned of the danger from multisystem inflammatory syndrome, a rare but serious condition affecting some minors weeks after recovery.

"After recovering from a Covid-19 infection, children may experience high fevers lasting about two to six weeks, potentially reaching 39 degrees," he said.

"Additionally, other symptoms can include rashes on the body, with some appearing as red spots.

"Inflammation may also occur in various organs, such as the liver and heart."

The Centre for Health Protection has expressed these concerns, urging residents to bolster hygiene practices and ensure timely vaccinations as key Covid indicators reach one-year highs.