Japan has begun a study on whether it should administer third shots of the coronavirus vaccine next year, officials have said.

Spurred by the likelihood of waning vaccine efficacy over time and the need to respond to highly infectious virus variants, the government will proceed with the study while trying to secure the supply of at least 200 million doses next year, the officials said Friday.

Tokyo will reach a decision on the matter after taking into consideration the situation of virus infections and how other governments are dealing with COVID-19 booster shots.