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Preparation for a booster
Japan's health ministry is planning to provide COVID-19 vaccine booster shots from December and has asked local authorities to prepare venues and reservation systems. The shots will be offered to anyone who has received two shots of the Pfizer-BioNTech, Moderna, or AstraZeneca vaccines.
The ministry says 65 percent of the population has now had two shots. But the duration of the vaccines' efficacy is still unclear and "breakthrough" infections, which occur two weeks or more after the second dose, are being reported in Japan and overseas.
Countries such as Israel, the U.S., the U.K., France, Germany, and Singapore are already offering boosters. Eligibilities vary by nation.
Eligibility
In Japan, medical workers were the first to receive the initial shots and will be at the head of the line again. They should be able to receive boosters from December. The elderly and anyone who completed their two shots in May will be the next.
The ministry says people will need to have waited at least eight months since their second shot, and will receive the same brand vaccine as their first and second shots.
Efficacy
Pfizer says the level of neutralizing antibodies detected one month after the booster was far higher than one month after the second shot. For people aged 55 or younger it was five times higher, and for those aged 65-85 it was up 11-fold. Moderna and AstraZeneca also both reported spikes in the number of antibodies after a booster.
Pushback from experts
The booster plan has generated controversy in Japan, where some immunology experts argue the government should be focusing instead on raising the rate of initial doses.
"Completing the two-dose regimen is a higher priority," says Okada Kenji, president of the Japanese Society for Vaccinology. "We should carefully weigh the infection situation before rushing to offer the third shots."
But Okada acknowledges that it is important to lay the groundwork for booster shots in light of the breakthrough cases being reported and the gaps in our knowledge about the virus.
The World Health Organization is also calling on governments to refrain from offering booster shots before the end of the year. The organization says the priority should be getting vaccines to developing countries where they are in short supply.
This information is accurate as of October 14, 2021.