More than a quarter of Covid-19 patients in Hong Kong this month had been vaccinated, most of them imported cases according to a Post review, raising concerns over the government’s scheme of halving quarantine periods for most arrivals from around the world.
But the Hospital Authority has refused to say how many of those ended up in a severe, serious or stable condition.
Since the start of the pandemic, there have been 20 confirmed imported cases involving people who had been fully vaccinated, meaning they had completed their Covid-19 vaccination for at least 14 days, the Department of Health also revealed on Tuesday.
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Two independent health experts believed the data was particularly alarming given that the United States and most of Europe were easing lockdowns on the back of their vaccination programmes at a time when the Delta variant was spreading quickly and gaining dominance.
Hong Kong’s relaxed travel arrangement, in place since June 30, allowed fully vaccinated residents to take an antibody test in the city, travel overseas to high and medium-risk countries, test negative for the virus upon arrival, and do seven days of hotel quarantine, plus three more tests afterwards, on their return.
One expert, Dr Leung Chi-chiu, believes the next phase of the scheme, slated to come into effect later this month, which involves the same shortened quarantine for those travellers who only need to clear an antibody test on arrival at the city’s airport, should now be scrapped.
“It’s like keeping the goal at only one side of the net. We have left our right flank completely open with this loophole in our quarantine system,” said Leung, a respiratory medicine specialist who was a former chairman of the Medical Association’s advisory committee on communicable diseases.
“If the policy is not scrapped, we will be bracing ourselves for more fully vaccinated imported infections.”
Hong Kong has confirmed 42 Covid-19 infections so far this month, 40 of which were classified as imported or import related. A Post review of the official data shows that in at least 11 cases, people had been vaccinated, and 10 of those were imported or import-related.
In nine cases, the people had been fully vaccinated, most of them with the German-made BioNTech vaccine, except one who had taken the Sinopharm jabs made in mainland China, while another had received the Russian-made Sputnik V doses.
The residents had arrived in the city from the United States, France, United Arab Emirates, Namibia, Cyprus, Greece and South Korea, all of which are on the Hong Kong government’s list of high-risk or medium-risk countries, meaning they could have taken a seven-day quarantine if they had tested positive for Covid-19 antibodies before they left the city.
On Tuesday alone, three of the seven new infections involved fully vaccinated travellers. One of them, arriving from France, received two doses of the BioNTech vaccine on April 6 and 27 in Hong Kong, and his blood specimen tested positive for the anti-spike protein antibody on June 23.
Leung said the spate of cases meant Hong Kong should return to its 14-day isolation regime for arrivals from high and medium-risk countries, adding Singapore was facing a similar problem, with some 190 patients found to have been fully vaccinated in the past 28 days. That compares with about 240 patients who had not been vaccinated in the same period.
Leung suggested one reason was that current vaccines were first-generation ones modelled on the original strain of the virus first detected in Wuhan, making them less successful in protecting against the new variants.
Dr Joseph Tsang Kay-yan, another respiratory medicine specialist, said that even though data on the vaccines’ effectiveness against new variants was lacking, research in Britain did find the BioNTech vaccine was 88 per cent effective against symptomatic disease, meaning severity and hospitalisation rates would still be down.
He believed Hong Kong could still keep the policy framework of the shortened quarantine, but had to be agile and respond quickly to the evolving pandemic in other countries, so it could take those virus hotspots out of the programme, and put them back in the top tiers of extremely or very high-risk groups. People from those countries would either face an entire entry ban or a tougher 21-day quarantine.
Government pandemic adviser Professor David Hui Shu-cheong, however, struck a more conservative note, saying he believed the current arrangements could stay.
“For those who have been vaccinated and tested positive for antibodies, there is still some sort of protection. Also, they do not go back home immediately upon arrival and are still subject to tests,” Hui said.
While the coronavirus variants had reduced the efficacy of Covid-19 vaccines, the viral loads for those who had been inoculated and their chances of developing symptoms were still lower after getting infected, he said.
Additional reporting by Rachel Yeo
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This article Coronavirus: more than a quarter of patients in Hong Kong this month were fully vaccinated, and with most imported, experts question plan to halve quarantine times first appeared on South China Morning Post