Omicron cases are appearing worldwide, as the antibody produced from COVID-19 vaccine will be decreased, many nations have started their COVID-19 vaccine boosters campaign. The HKSAR government announced the 3rd dose COVID-19 vaccination arrangements in November 2021. As of 22 February 2022, there are 1.5 million people in Hong Kong who received their 3rd dose. The vaccination rate (Total number of people who received at least 1 dose) is 88.6%. And there are 100,000 aged 3 -11 who have received their 1st dose of the COVID-19 vaccine.
Booster shot for vaccination priority groups
The HKSAR government refers to the suggestions from the Scientific Committees under CHP and the Chief Executive's expert advisory panel (EAP), announced the suggestion to receive the 3rd dose of booster shot as below:
- Immunocompromised individuals (Aged 12 or above): Including cancer patients, recipients of solid organ transplants, patients with advanced HIV disease, people on active immunosuppressive drugs, and those who are on chronic dialysis. If they want to receive the booster shot, they have to wait at least 28 days after the second dose, and bring the relevant medical certificate to the designated vaccination venue on the day of the booster shot. The official suggested the group above receive Comirnaty (BioNTech) vaccine.
- For those who received CoronaVac (Sinovac) or Comirnaty (BioNTech) vaccine and aged above 18, the official suggested this group could receive the booster shot 180 days after the 2nd dose. Comirnaty (BioNTech) vaccine was recommended.
- Individuals with personal needs, including travel across borders or at higher risk of COVID-19 exposure and those who have a higher risk of the virus. This group of individuals could receive their booster shot after 90 days of the second vaccination dose.
- For pregnant women and lactating mothers can be treated as adults, and Comirnaty (BioNTech) vaccine is also recommended.
For those who recovered from COVID-19, the officials suggested receiving their first Comirnaty (BioNTech) vaccine at least 90 days after they are discharged from the hospital and at least 180 days for CoronaVac (Sinovac) vaccine. These individuals can receive the second dose after 180 days of the first dose. Comirnaty (BioNTech) vaccine is also recommended.
Booking for the third dose vaccination
You can book for the booster shot via the “COVID-19 Vaccination Programme” website, available venues including Community Vaccination Centers across Hong Kong, 3 Pop-up Community Vaccination Centers and some of the general out-patient clinics, designated clinics of Hospital Authority, Hospital COVID-19 Vaccination Stations, some private clinics and Mobile Vaccination Stations. You can receive the booster shot in all venues above.
Citizens above 60 are eligible for the same-day tickets and receive the vaccination; their family members are authorized to get tickets on the senior citizen’s behalf. The authorized family member needs to present a copy of the authorizer's HKID card; the same-day tickets are distributed daily from 7:45 am on a first-come, first-served basis.
COVID-19 Vaccination for Children and Teenagers
Parents can now make a vaccination booking on behalf of their children aged 3 -11. For the CoronaVac (Sinovac) vaccine, venues like Community Vaccination Centers, Student Health Service Center, Hong Kong Central Library and general out-patient clinics are available. And for the Comirnaty (BioNTech) vaccine, 3 Children Community Vaccination Centers in Hong Kong Children's Hospital, Gleneagles Hospital Hong Kong, and Yuen Chau Kok Sports Centre are available for children aged above 5 years old.
Prof Hung Fan-Ngai Ivan, the co-conveners of the Expert Committee on Clinical Events Assessment Following COVID-19 Immunization, said that according to phase III clinical data, the side effects of teenagers aged 12-15 are mild; most of them experienced tiredness, fever, and sorenesses. The side effects are lesser than adults, while he reminded teenagers not to engage in strenuous activities like sprinting and soccer after the first week of vaccination. And the Center for Health Protection listed pericarditis and myocarditis as known adverse effects, mostly happening to teenagers who receive the second dose. Teenagers and youngsters should avoid strenuous activities after the first week of vaccination.
The Society of Hospital Pharmacists of Hong Kong said that some teenagers have autoimmune diseases like Asthma or multiple sclerosis, and they may undergo biologic therapy that will inhibit the immune system and the reaction to the vaccine decreased,The Society of Hospital Pharmacists of Hong Kong recommended that they should seek for doctor's advice for the best time for vaccination.
For the children and teeangers aged 3 -17 receiving CoronaVac (Sinovac) vaccine, they will encounter side effects like soreness, induration wound, coughing, rhinorrhea, fever, losing appetite, headache, tiredness and sore throat. Reactions like itchiness over the injected part, erythrose, diarrhea, and muscle soreness are rare among those who receive vaccines.
The joint study found the Booster shot of Comirnaty (BioNTech) could provide better protection against the Omicron Variant
A joint study conducted by the LKS Faculty of Medicine, The University of Hong Kong, and the Faculty of Medicine, The Chinese University of Hong Kong found that the third dose of Comirnaty (BioNTech) vaccine provides protective levels of protective antibody against the Omicron variant. The study found that only two doses of vaccination provide little antibody responses against the Omicron variant, which means it could not provide protection against the Omicron variant.
The study shows the third dose of the Comirnaty (BioNTech) vaccine provides protective levels of the antibody against the Omicron variant. All 23 individuals with three doses of the Comirnaty (BioNTech) vaccine have a high level of antibodies that can protect them against the Omicron variant. For 10 individuals who had CoronaVac (Sinovac) vaccine for the first two doses, the third dose of Comirnaty (BioNTech) also provided enough antibodies to 9 of them. For the 10 individuals who chose CoronaVac (Sinovac) vaccine as their third dose, their antibody level is not enough to protect themselves from the Omicron variant. Professor David Hui Shu-Cheong, who is one of the leaders of the study, claimed that no matter which vaccine people choose, the third dose should be Comirnaty (BioNTech) vaccine, but he will respect individuals’ choices.
Another Study Found the Protection from Covid-19 Vaccine Will Be Decreased As Time Passes
A study from University of Oxford found that the antibody produced by Pfizer-BioNTech and the Oxford-AstraZeneca COVID-19 vaccine will decrease significantly 90 days after, making it less effective against the Delta variant.
The researchers analyzed over 3 million nose and throat swabs between December 2020 to August 2021 and found results as below:
| Protection Rate | Pfizer-BioNTech | Oxford-AstraZeneca |
| 14 Days After Vaccination | 85% | 68% |
| 90 Days After Vaccination | 75% | 61% |
The decrease is more significant in people aged above 35 which is a concern. The research team believes that the vaccine provides similar protection after 4-5 months of injection, the vaccine performed well against the Delta variant but it is less effective against Alpha variant (Another variation of COVID-19). The study also found that the vaccinated carried Delta variant viruses as much as unvaccinated people, which means both groups of people would have the same risk of spreading the virus but the vaccinated would have better protection against it. The researcher believes that the study showed that a booster shot is necessary for the vaccinated.
USA is considering making the fourth dose available
The US government had approved the booster shot for US citizens. The Centers for Disease Control and Prevention (CDC) released a report in mid-February 2022, and it claims that the antibody level of the third dose vaccine by Pfizer and Moderna will significantly decrease after the fourth month of injection, which means they need the fourth dose soon.
The Vaccine Administration Protocols were updated in October 2021. The protocols recommended Pfizer and Moderna as the fourth dose to the targeted groups, including immunocompromised individuals. Around 9 million will need to receive the fourth dose, as 2% of the US population. CDC also updated the definition of doses. For immunocompromised individuals, the third dose is the “Additional dose,” while the fourth dose is the “Booster” for them, and the fourth dose should be half of the previous doses. As of February 2022, 93 million across the US had their third dose of the vaccine.