Health officials in Hong Kong and Singapore have issued warnings about a surge in Covid-19 cases as a new wave of infections spreads across Asia, Bloomberg reported on Friday.

In Hong Kong, the virus is now circulating at "quite high" levels, according to Albert Au, head of the Communicable Disease Branch at the city's Center for Health Protection, the report said. The proportion of respiratory samples testing positive for Covid-19 has recently reached its highest level in a year. Severe cases, including deaths, have also risen sharply, reaching 31 in the week ending May 3, the highest figure in nearly a year, according to the Center's data.

While the current resurgence has not yet matched the record infection spikes of the past two years, indicators such as rising viral loads in sewage water and an increase in Covid-related medical consultations and hospitalisations suggest active transmission in the city of more than 7 million people, the news agency reported.

Singapore, a rival financial hub, is similarly on high alert. The city's health ministry released its first infection update in nearly a year this month, revealing that the estimated number of Covid cases surged by 28% to 14,200 in the week ending May 3, compared to the previous week, reported Bloomberg. Hospitalisations also saw a 30% increase. Singapore now only provides case updates when there is a noticeable spike in infections.

Singapore, too, is seeing a surge in Covid-19 cases. The recent rise in Covid-19 cases may be linked to factors such as declining population immunity, but Singapore’s health ministry has emphasised that there’s no evidence suggesting the current variants are more contagious or cause more severe illness than those seen during the pandemic, the report noted.

The uptick in cases in two of Asia's largest cities comes as Covid has been making a comeback across the region over the past few months, with periodic waves of the now-endemic virus. Health officials have urged the public to keep their vaccinations up to date, especially reminding high-risk groups to get booster shots.

Unlike other respiratory diseases that tend to peak in colder months, Covid’s resurgence as much of the northern hemisphere enters summer demonstrates that the virus can still affect a significant portion of the population even in warmer weather.