A Hong Kong health expert has said that those who are at higher risk of contracting Covid-19, such as people with chronic illnesses and healthcare workers, should receive a fourth dose of a Covid-19 vaccine.
Last Friday, the government said that adults aged 18 to 59 “may choose” to be quadruple jabbed if they were “at a higher risk of Covid-19 exposure or with personal needs,” but advised waiting for at least six months from the third dose.

The fourth shot became available to all adults on Saturday. Same-day tickets for both BioNTech or Sinovac shots are available at community vaccination centres and hospital vaccination stations.
Online booking for the fourth jab will begin on Thursday morning.
The government made the fourth jab available to people aged 60 or above last month.
High-risk groups
While Siddharth Sridhar, a microbiologist at the University of Hong Kong, told HKFP on Monday that it “doesn’t make that much sense” for healthy individuals to get a fourth jab, he recommended younger people with chronic illnesses – but who may not fall under the category of immunocompromised individuals allowed to get the fourth dose earlier – to receive the booster.
“There are always people in their 40s or 50s who have chronic diseases such as heart, lung or kidney issues. These are people at risk of severe Covid,” he said.

“I think the important thing is just to realise that this is an avenue for some high risk individuals below 60 to get some protection against Covid, especially if they have not been infected in the fifth wave.”
Sridhar also said groups with higher risk of coming into contact with Covid-19 patients, such as healthcare workers, could consider getting a fourth jab.
“If we’re talking about a young, healthy individual, you’re basically reducing already a very low risk of [contracting] severe Covid to an even lower risk,” Siddharth Sridhar, a microbiologist at the University of Hong Kong, told HKFP on Monday.
“You’re already in the zone of diminishing returns from each additional jab,” he said, adding that three doses already puts one in a “very good position.”

“What we should in no circumstances do is make this mandatory,” Sridhar said, adding that he did not wish to see a fourth jab being mandated under the Vaccine Pass. The third phase of the Vaccine Pass scheme will come into effect on May 31, by which time people must have received three Covid-19 vaccine doses to enter restaurants, gyms and other businesses under the scheme, unless they have certain exemptions.
Focus on vaccinating the elderly
Speaking on an RTHK radio show on Monday, Lau Yu-lung, chair professor at the Department of Paediatrics and Adolescent Medicine in the University of Hong Kong said the protection from the fourth Covid-19 jab would only last one or two months.
Lau said the city should instead prioritise promoting the third jab among those over the age of 80. Just 20 per cent of that age group were triple jabbed, he added.
According to Sunday night data on the government’s Covid-19 vaccination dashboard, 53.3 per cent of the population have received three vaccine doses. Just over 86 per cent have received two.
Hong Kong’s Covid-19 outbreak has eased significantly in recent weeks. Authorities confirmed 237 new infections on Sunday, 25 of which were imported.
In total, the city has recorded 1,210,396 Covid-19 cases and 9,370 deaths since the epidemic began.
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