Japan began offering fourth coronavirus vaccine shots Wednesday to older people, and those with underlying medical conditions.

People eligible for fourth inoculations are those aged 60 and older as well as individuals between 18 and 59 with chronic health conditions, such as respiratory illnesses or heart conditions, or at high risk of developing severe COVID-19 symptoms if infected with the coronavirus, according to the health ministry.

The ministry suggests people receive the booster shots at least five months after receiving their third inoculation. The majority of seniors began getting third shots in January, meaning that the fourth round of shots is expected to be in full swing from June onward.

Photo taken on May 25, 2022, shows a COVID-19 booster shot at a facility in Tokyo, as administration of fourth vaccine doses began in the capital for people aged 60 or older and those with chronic illnesses. (Kyodo)

Procedures for receiving vaccine tickets differ depending on residents' local governments, with some tickets being sent directly to eligible individuals, while others need to be applied for.

To confirm eligibility and avoid confusion, the Ministry of Health, Labor and Welfare is asking people to check with local governments and to pay attention to public announcements.

Overseas studies have shown that fourth vaccine shots can prevent severe COVID-19 symptoms from developing in people over 60 for a certain period of time.

The studies, however, did not show sufficient data for effectiveness for those under that age.

A government official touched on the possibility of expanding the scope of those eligible, saying, "We will make considerations while continuing to collect a range of information."

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