Bookings for COVID-19 vaccinations in Hong Kong were up roughly eight fold this week, days after the Pfizer vaccine was made available in the city and eligibility restrictions were lifted to include another 5.5 million residents.

Until now, many residents expressed concern about potential side-effects, especially in the Chinese-developed Sinovac jab that has been linked to seven deaths in elderly and sick individuals so far.

On Tuesday, the first day bookings could be made among people aged 30 and up, appointments to get the vaccine soared to 144,000 from 18,600 Monday.

Asides from those aged 30 to 59, people eligible to receive their first dose of the vaccine include those working in the tourism industry, helpers for the elderly, people with pre-existing conditions, foreign domestic workers and students studying overseas.

Despite the recent uptick in vaccinations, stringent social distancing measures which were supposed to expire Wednesday, including dining-in restrictions after 10 pm and a 4 person limit to public gathering, were extended until March 31.

"Taking into account the latest public health risk assessment, there is still no room for further relaxation of measures at this stage," a spokesperson for the food and health bureau said.

Hong Kong reported 18 new cases Tuesday, including five linked to the Ursus Fitness center cluster that has grown to 127 infections and seen nearly 900 people sent to government quarantine facilities.

"A very large group of infections have emerged again and the SAR government is ready to strengthen our relevant measures," city leader Carrie Lam said Tuesday.

Health authorities in Hong Kong expect to record at least 10 cases Wednesday, as they trace new infections among workers at HSBC and the American Consulate in Central.

Three employees at the bank and two consulate workers tested positive for the virus this week, forcing both locations to close their doors indefinitely as the buildings undergo deep cleaning.