Speaking on a radio program on Friday, respiratory disease expert Leung Chi-chiu said getting a third shot with the same vaccine used for the second one will lower the chance of serious side effects and allergic reactions.

“The World Health Organization had earlier released guidelines saying that people who did not experience serious side effects should get the same vaccine for their third jab,” said Leung.

“From a safety point of view, getting the same vaccine lowers the chance of serious complications and the uncertainty of mix-and-matching the vaccines,” Leung added.

Meanwhile, the health expert pointed out that some overseas countries are looking into the possibility of a fourth jab.

He also suggested that people from groups vulnerable to Covid should continue their anti-pandemic practices and avoid traveling to high-risk areas to avoid getting infected.

Bookings for the third dose of the vaccine have been made available to immunocompromised persons by the HK govt from today (Nov 5), with the administering of the booster shot starting next week Thursday (Nov 11).