The Hong Kong SAR government announced on the 21st that people aged 18 to 59 who have not been infected can choose to receive the fourth dose of neocoronavirus vaccine from the same day if they have high exposure risk or personal needs. It is reported that from May 21 to 25, citizens eligible for the fourth dose of Xinguan vaccine can go to community vaccination centers or Xinguan vaccination stations in public hospitals to receive "on-the-spot" vaccination; From 8 a.m. on May 26, citizens can make an appointment for vaccination services through the website of the new crown vaccination plan. Experts suggest that the time between the fourth dose and the third dose should be at least 6 months. Rehabilitated persons in this age group can also receive the third dose of vaccine after completing the second dose of vaccine or 6 months after rehabilitation (whichever is the later). A spokesman for the SAR government said experts believe that the fourth dose of the new coronavirus vaccine may provide temporary additional protection for younger adults to prevent infection and symptoms. (Xinhua News Agency)