Countries that are considering, or have decided to adopt, the mixed-vaccine solution for their second doses or booster shots:
Bhutan’s Prime Minister Lotay Tshering said on June 24 he was comfortable about mixing and matching Covid-19 vaccine doses to immunise the country’s population of about 760,000 people.
The National Advisory Committee on Immunisation said on June 17 that the provinces should offer recipients of a first dose of the AstraZeneca vaccine a different shot – the Pfizer-BioNTech or Moderna mRNA vaccines – for their second dose.
Researchers are running a trial using one dose of CanSinoBIO’s viral vector-based shot as a booster for those who have received one or two doses of an inactivated vaccine, clinical trial registration records in June show.
Indonesia started giving a Moderna booster shot to its healthcare workers immunised with the Sinovac vaccine, as thousands of them tested positive for Covid-19 in July. On July 27, the Indonesian government said it is mulling booster shots for the rest of the population.
Italy’s medicines agency, Aifa, said on June 14 that people under the age of 60 who were inoculated with a first dose of the AstraZeneca shot can receive a different second shot.
On July 26, Russia approved clinical trials combining an AstraZeneca shot with its Sputnik V vaccine, according to the country’s state drug register.
A study from South Korea found in July that a mixed vaccination of an AstraZeneca shot first and then a Pfizer-BioNTech one boosted neutralising antibody levels six times more than two AstraZeneca doses.
Thailand said on July 12 it would use an AstraZeneca shot as a second dose for people first inoculated with Sinovac in an attempt to increase protection.
UNITED ARAB EMIRATES
The UAE, which initially used the Sinopharm shot, started making the Pfizer-BioNTech vaccine available as a booster in July.
Vietnam said on July 13 it would offer the Pfizer-BioNTech mRNA vaccine as second dose option for those who received the AstraZeneca vaccine as their first dose.