Feature article: Toward an exit strategy  – Booster vaccinations –
December 3, 2021
At present, the fifth wave has been brought under control in Japan and the infection situation is relatively stable. On the other hand, it is still necessary to consider measures that allow economic activity to recover and prevent infections spreading again in the medium to long term.
There are thought to have been multiple factors involved in bringing the fifth wave under control, including the thorough implementation of basic infection protection such as vaccinations, avoidance of risk behaviors, masks and avoidance of the “Three Cs,” as well as seasonal factors. At the same time, a fundamental difference with the previous phase of spread and control has been the rapid progress of vaccinations, which suppressed infections to a level far lower than during the previous phase of control. Although the start of vaccinations was slower than other countries, as a result of continuing vaccinations at more than one million a day for about three months from June, as of October 20, the rate of vaccinations administered to the total population has reached more than 76% for the first dose and more than 68% for the second dose. 1.
Meanwhile, there is continued debate on how far the rate of vaccination of the total population should be raised to prevent infections from spreading again, and when booster doses should be given in view of the reduction in vaccine efficacy over time.
※It should be noted that the following are the results of calculations and simulations by researchers, and not the official opinion of the national government.