Japan's Rapid COVID Vaccine Campaign Partially Credited With Lowering Cases

Japan has seen a low in coronavirus cases recently which may be due to the success in its vaccination campaign after a summer wave that peaked at nearly 6,000 daily cases.

Weeks later, COVID-19 cases have plummeted below 100 in Tokyo marking an 11-month low.

While some are baffled as to the steep decline, others say possible factors in Japan's new numbers include a remarkably rapid COVID vaccination campaign.

Other reasons, some say, are Japan forcing many nightlife attractions to close down and the practice from Japanese of wearing masks during days of high pollution or when ill.

"Rapid and intensive vaccinations in Japan among those younger than 64 might have created a temporary condition similar to herd-immunity," said Dr. Kazuhiro Tateda, a Toho University professor of virology.

Nearly 70 percent of the population is fully vaccinated. Japan has never had a pandemic lockdown, instead the country has been in multiple states of emergency.

However, experts worry going into the colder months not knowing the exact cause as to why cases have dropped drastically.

Japan's sudden virus success leaves experts puzzled
Japan has become an almost overnight success with dramatic drop in virus cases. In this Oct. 12, 2021, file photo, people wearing protective masks are reflected in a puddle as they walk across a street in a shopping district, in Tokyo. Kiichiro Sato/AP Photo

For more reporting from the Associated Press, see below.

So why the drop?

"It's a tough question, and we have to consider the effect of the vaccinations progress, which is extremely big," said Disease Control and Prevention Center Director Norio Ohmagari. "At the same time, people who gather in high-risk environments, such as crowded and less-ventilated places, may have been already infected and acquired natural immunity by now."

Though some speculated that the drop in cases might be due to less testing, Tokyo metropolitan government data showed the positivity rate fell from 25 percent in late August to 1 percent in mid-October, while the number of tests fell by one-third. Masataka Inokuchi, the Tokyo Medical Association deputy chief, said falling positivity rates show infections have slowed.

Japan's state of emergency measures were not lockdowns but requests that focused mainly on bars and eateries, which were asked to close early and not serve alcohol. Many people continued to commute on crowded trains, and attended sports and cultural events at stadiums with some social distancing controls.

The emergency requests have ended and the government is gradually expanding social and economic activity while allowing athletic events and package tours on a trial basis using vaccination certificates and increased testing

To speed up inoculations, former Prime Minister who left office recently, expanded the number of health workers legally eligible to give shots, opened large-scale vaccination centers and promoted workplace vaccinations beginning in late June.

Kyoto University professor Hiroshi Nishiura told a recent government advisory board meeting that he estimates vaccinations helped some 650,000 people avoid infection and saved more than 7,200 lives between March and September.

Many experts initially blamed younger people, seen drinking on the streets and in parks when the bars were closed, for spreading the virus, but said data showed many in their 40s and 50s also frequented nightlife districts. Most serious cases and deaths were among unvaccinated people in their 50s or younger.

Takaji Wakita, director of the National Institute of Infectious Diseases, told reporters recently he is worried people have already resumed partying in nightlife districts, noting that the slowing of infections may have already hit bottom.

"Looking ahead, it is important to further push down the caseloads in case of a future resurgence of infections," Wakita said Thursday.

Public health experts want a comprehensive investigation into why infections have dropped off.