A nurse holds her arm after receiving the Sinovac vaccine in Hong Kong. Photo: Peter Parks / AFP

More than 70,000 people in Hong Kong have registered to get the Sinovac vaccine from Friday, with indications many want to travel to the mainland without being quarantined.

On Tuesday at midnight, the government’s vaccination registration website started allowing people to make appointments. The booking system overloaded at about 12:40am but the problem soon resolved itself. Many people spent 40-60 minutes registering.

Due to an error in the booking system, about 110 people were mistakenly allowed to book slots on Tuesday. They were given the shots on the same day. Many of them said they had full confidence on the Hong Kong government and the mainland vaccine. They said they hoped to have quarantine-free travel to the mainland after the second shot 28 days later.

As of 4pm on Tuesday, all the time slots between February 26 and March 11 had been reserved, according to the government. About 1,500 private clinics will provide the vaccine from March 2 or 3.

“The registration opened at midnight. Most citizens were sleeping, but some of them couldn’t wait and booked their vaccination. The response is enthusiastic,” Chief Executive Carrie Lam said before the weekly Executive Council meeting.

Lam said she and top officials who received the Sinovac jabs on Monday had not experienced any side effects. She said she didn’t even feel any pain where the injection was administered.

She said the government would continue to educate the public about the benefits of getting vaccinated, and quickly clarify false claims about the vaccines.

“It’s expected that there would be unfounded reports aimed at smearing the vaccination program,” she said.

“Several hours after government officials and I received the vaccine, rumors circulated online saying the jabs we took were not produced by Sinovac as we didn’t have confidence in the vaccine. We clarified immediately.”

A production line of Sinovac vaccines in Beijing. Photo: Xinhua

On Monday, top government officials received the mainland vaccine taken out from bottles during a live broadcast. Netizens suspected that the Hong Kong officials could have received a vaccine other than the Sinovac one, which should be packaged in syringes, instead of bottles.

The government clarified that it bought the bottle version of the Sinovac vaccine and offered it to officials on Monday.

Ho Pak-leung, the head of the University of Hong Kong (HKU) Center for Infection, said the inoculated officials did not feel pain because mini needles were used. Ho said the needles of the syringe-version of the Sinovac vaccine were thicker.

According to local media, the first million doses of the BioNTech vaccine will arrive in Hong Kong from Germany on Thursday. They will be available at 24 community vaccination centers soon.

In his blog, Chief Secretary Matthew Cheung urged people to get the jabs to protect themselves and others. He said people didn’t want to see a fifth wave of Covid-19 infections. The chance of another outbreak would decrease if more people were inoculated.

While officials are actively promoting the Sinovac vaccine, medical experts tend to wait for the Western ones. The Sinovac vaccine has an overall efficacy rate of 50-60%, which is lower than the 95% efficacy of the BioNTech vaccine and the 81% of the AstraZeneca/Oxford one.

Hong Kong Police Commissioner Chris Tang gets his injection at a community vaccination center. Photo: Paul Yeung/ AFP

Gabriel Matthew Leung, Dean of Li Ka Shing Faculty of Medicine of the HKU and a member of an expert advisory group to provide public health advice to the government, said he would get the BioNTech vaccine, which would be available in a vaccination center operated by the HKU. He said he had a moral responsibility to be vaccinated there as he was the dean of the HKU’s medicine faculty.

Yuen Kwok-yung, a microbiologist at the HKU, said he preferred to get a nasal spray vaccine co-developed by HKU’s State Key Laboratory of Emerging Infectious Diseases, Xiamen University and Beijing Wantai Biological Pharmacy.

Last November, Yuen said the HKU had been given about HK$20 million (US$2.6) by the government to develop the world’s first nasal spray Covid-19 vaccine. He said the third phase of clinical trials would be carried out late this year.

David Hui Shu-cheong, chairman of the Department of Medicine and Therapeutics at The Chinese University of Hong Kong, said he would not say which vaccine he would get as he did not want to politicize the matter.

Benjamin Cowling, head of the Division of Epidemiology and Biostatistics at the HKU School of Public Health, told i-Cable it would be harder to achieve herd immunity with the Sinovac vaccine than others due to its low efficacy.

The immunity level in the population could reach 60-70% only if all people in Hong Kong were given a highly-effective vaccine like the BioNTech vaccine, Cowling said.

“Later this year we might look back and regret because we have not got the level of immunity in the population that we would like to have,” he said. “After people have received the Sinovac, I don’t know whether we can still go back to give them another vaccine to boost them up.”

“There is an urgency to get people vaccinated. But the urgency is not to get the first person in Hong Kong vaccinated. I don’t mind if we wait a bit now to get the right vaccine to line everything up in the right way. Let’s make sure we are doing the right things for Hong Kong,” he said.

Besides, Cowling said it was too early to have relaxed some of the social distancing rules last week as some local cases were recorded in the city every day. He said the government should only consider further relaxing the rules two weeks after no cases were reported.

The Center for Health Protection said 12 cases, one imported and 11 local, were recorded on Monday. Three local cases were untraceable. Ten more patients tested positive preliminarily.

Read: Tale of two cities as Beijing and HK differ on jabs

Read: Hong Kong counts down for Feb 26 vaccinations