Please view the main text area of the page by skipping the main menu.

Shortage of COVID-19 vaccines in Japan prompts debate on spacing out 1st, 2nd doses

A nurse receives her second dose of the coronavirus vaccine at Osaka Toneyama Medical Center in the Osaka prefectural city of Toyonaka, on March 12, 2021. (Mainichi/Satoshi Kondo)

TOKYO -- In response to shortages in the Japanese government's supply of coronavirus vaccines to local governments, local bodies have started asking for permission to extend the interval between the two doses that people receive.

    At an online meeting of prefectural governors on July 11, Okayama Prefecture Gov. Ryuta Ibaragi pointed out that in the U.K., the second vaccination shot was given up to a maximum of 12 weeks after the first shot, and said to the Japanese government, "Amid the decrease in vaccine supplies, we request consideration be given to extending the interval between vaccination shots from the current three weeks."

    The disruption stems from the central government's misjudgment of the balance between vaccine supply and local governments' demand as it has surged forward with the vaccination rollout. The second dose of the Pfizer vaccine is meant to be received three weeks after the first dose. The government argues that municipalities have a certain "stock" of unused vaccines. But local governments counter that those vaccine doses are the second doses set aside for people who have already gotten their first shots, and are not extra "stock."

    Hidekiyo Tachiya, mayor of the Fukushima Prefecture city of Soma who is also a physician and president of the Japan Association of City Mayors, on July 15 submitted a recommendation regarding the period between vaccine shots to Minister in charge of Administrative Reform Taro Kono and the Ministry of Health, Labor and Welfare. It called for Kono and the health ministry to consider from a medical standpoint the period between the two doses, which is currently set at three weeks as a general rule.

    That raises the question: Would there be any problems with spacing the first and second doses of the vaccine further apart?

    The University of Birmingham in the U.K. and other institutions released research results on the Pfizer vaccine this past May. It showed that those aged 80 and over who had received their second dose of the vaccine 11 to 12 weeks after their first dose had an average concentration of antibodies that was 3.5 times higher than that of the same age group who received their second dose three weeks after their first.

    According to health ministry documents, in the U.S. and some European Union member countries, intervals between the two doses are said to be "possible up to six weeks." Furthermore, in June, the World Health Organization (WHO) changed its policy of recommending intervals of up to six weeks to a maximum of 12 weeks.

    It is known that receiving just one dose of the vaccine does not provide sufficient protection against the delta variant of the coronavirus. According to survey results released by Public Health England on July 21, while receiving two doses of the Pfizer vaccine could help prevent symptoms from developing at a rate of 88%, with one dose, the rate was just 36%. But in terms of preventing severe symptoms of COVID-19, one dose could do so at a rate of over 90%. Initially, the U.K. permitted people to receive their second doses of the vaccine up to 12 weeks after their first dose. But the government changed its policy in May in response to the delta variant, and set the maximum interval at eight weeks for people with underlying health conditions and others.

    Director of Navitas Clinic, Eiji Kusumi, who is well-versed in vaccines, told the Mainichi Shimbun, "If the delta variant gains prevalence while many people have only received one dose of the vaccine, the number of people infected with the coronavirus will not decrease in society at large, putting a lot of pressure on the health care system.

    "We shouldn't be delaying giving people their second dose, but if there aren't enough vaccine doses, there's not much we can do. Giving people even one dose can decrease the number of people who develop severe symptoms and those who die." Kusumi added that even if the second dose were delayed, ultimately, the effects anticipated by receiving two doses in preventing infections and the onset of symptoms would still stand.

    On a July 17 television program, Prime Minister Yoshihide Suga expressed his intention to aim to have all people who wish to be inoculated vaccinated by October or early November.

    (Japanese original by Naomi Hayashi, Lifestyle and Medical News Department)

    Also in The Mainichi

    The Mainichi on social media

    Trending