Authorities have set up a makeshift hospital in a sports dome near the city's Las Vegas style Cotai strip and have around 600 medical workers from the mainland assisting them.

Travelling to Hong Kong will still pose a challenge as the city holds on to its mandatory seven-day hotel quarantine for all arrivals.

The subvariants have now become the dominant coronavirus strains in several countries, with experts warning they could lead to more hospitalisations and deaths because they spread more quickly than other variants.

Chinese health authorities have reported more than 300 infections in the historic northern city of Xi'an – home to the Terracotta Army – with new clusters found in Shanghai, Beijing and elsewhere.

One Central shopping mall will be shut for one week, while more than a dozen other zones or buildings have also been ordered to close, authorities say.

The city is urging residents to get booster shots and is trying to persuade the elderly, a group with lower vaccination rate than younger adults, to be jabbed.

Shanghai, which lifted its two-month lockdown in early June, is testing all residents in nine of its 16 districts as well as those in parts of three other districts.

At least 16 other buildings across the special Chinese administrative region are also locked down with no one allowed to exit or enter.

The diversion of resources into what China calls its 'zero-Covid' approach to contain and eliminate the virus forced the hospital to suspend many services it relied upon for revenue, sealing its financial failure.

Over six million Israelis have received at least two Covid-19 vaccination shots, including 17% of the country's children aged five to 11.