Thailand’s Chulabhorn Royal Academy (CRA) is accepting registrations for AstraZeneca booster shots for those who have already had two doses of either the Sinovac or AstraZeneca vaccines, with jabs scheduled from October 20^th to March 10^th, 2022. Registrations for Moderna and Sinopharm booster shots will be open from October 29^th for organisations and hospitals.

For people who have received two doses of Sinovac at the CRA’s vaccination centre in June, July and August, the CRA will open registrations for third booster shots as follows:

• Those over 70 will receive booster shots from October 20^th to 29^th.
• Those aged 59-69 will receive them from November 1^st and 30^th.
• Those under 59 will receive the booster shots from November 15^th to December 24^th.
• Those of all ages with any of the underlying diseases can receive booster shots from October 20^th.

As for people who have received two doses of AstraZeneca at the CRA’s vaccination centre between July and September, the CRA will open registrations for third booster shots as follows:

• Those over 70 will receive booster shots from February 1s to 15^th, 2022.
• Those aged 59-69 will receive them from February 15^th to 28
• Those under 59 will receive the booster shots from March 1^st to 10^th.
• Those of all ages with any of the underlying diseases can receive booster shots from February 1^st.

The CRA also advised that AstraZeneca booster shots are NOT recommended for women under 40 years old, women under hormone-control medication or those who experience blood-clots.

It is also not advised to get vaccinated with booster shots too quickly, especially when the outbreak is not too severe, as data shows that, if the time frame between doses is longer, the immunity will be more effective.

Regarding the time frame between doses of each vaccine brand, inactivated virus vaccines, such as Sinovac and Sinopharm, should be used 3-6 months after the second dose. Other vaccine brands, such as AstraZeneca, Pfizer, Moderna, Johnson & Johnson and Sputnik-V, should be used 7-8 months after the second dose.

Those infected with COVID-19 after receiving their second dose should receive a booster shot 60 days after their infection.

The CRA also advises that using Sinovac or Sinopharm as booster shots may prevent infection and severe illnesses for 4-8 months, while other vaccines, such as AstraZeneca, Pfizer or Moderna, may prevent infection and severe illnesses for 8-10 months, depending which virus strain is dominant.

Therefore, people should still wear facemasks at all times, wash their hands frequently, maintain social distancing and avoid areas with limited air circulation.