TOKYO -- The fifth wave of the coronavirus that has hit Japan has resulted in an increase in cases among those under the age of 20 -- an apparent effect of the spread of the highly infectious delta variant. Day care centers in particular have seen a spate of COVID-19 clusters, and the number of centers that have temporarily suspended operations has quadrupled over the course of a month.
According to the Ministry of Health, Labor and Welfare, a total of 22,175 people under the age of 20 were infected with the coronavirus across Japan from Aug. 11 to 17. Of these, 7,441 were aged 9 or under, and 14,734 were aged between 10 and 19. Particularly in Tokyo, where infections have been spreading, there have been over 100 people under the age of 20 infected daily since mid-July, with the figure reaching a record high of 904 on Aug. 21. The proportion of under-20s infected among the total stood at 11% on July 1, but climbed to 17% on Aug. 23.
Yuho Horikoshi, chief physician in the Department of Infectious Disease at Tokyo Metropolitan Children's Medical Center in the suburban Tokyo city of Fuchu, said that in April and May, the number of child patients infected with the coronavirus was in the single digits, but since June, 10 to 20 of the 28 beds available for coronavirus patients have been filled.
In most cases the infected children had mild or no symptoms, but they were hospitalized due to circumstances at home, such as both of their parents having the virus and being hospitalized. In some cases, symptoms have included fevers, coughing, vomiting and diarrhea. In rare cases, intravenous drips have been required to keep fluid levels up, while pneumonia cases have necessitated the administration of oxygen or use of an artificial respirator.
According to a health ministry research team, around 70% of coronavirus infections of people under the age of 20 are occurring at home, with the infections believed to have come through their father in about half of the cases. But it has been pointed out that during the fifth wave, infection routes may have become diverse.
Associate professor Tomohiro Katsuta at St. Marianna University Hospital in the city of Kawasaki in Kanagawa Prefecture, south of Tokyo, commented, "There's no change to the fact that there are many infections within households, but infections at day care centers and other such facilities are also occurring. People are starting to have to take care about catching the virus from children."
Infections among the parent generation also stand out. In the week between Aug. 11 and 17, 60% of coronavirus cases were among people aged between their 20s and 40s. Katsuta commented, "Children under the age of 12 aren't getting vaccinated, so I'd like their parents to get vaccinated to prevent infections. Another thing is that there are many cases in which the actions of one adult result in an entire family becoming infected, so I want people to refrain from nonessential and nonurgent outings."
(Japanese original by Naomi Hayashi and Yuki Nakagawa, Lifestyle and Medical News Department)