Daily COVID-19 new cases have fallen from an August peak of almost 6,000 in Tokyo. Caseloads in densely populated areas are now below 100, an eleven-month low.
The bars are full, the trains crowded and the mood is celebratory, despite general confusion over the cause of the sharp drop.
Japan has not experienced a lockdown like other countries in Europe or Asia. It has only experienced a few relatively unimportant states of emergency.
Japan's success could be due to a late but very rapid vaccination campaign, the emptying of many nightlife areas because of fears that spread during the recent surge of cases, and a widespread practice of wearing masks in August, long before the pandemic.
Experts worry that Japan may face another wave of cases like the one in which Japan experienced a severe spike in deaths and hospital overcrowding this summer. However, vaccine efficacy is slowly declining and winter is approaching.
Many people credit the vaccination campaign for reducing infections, particularly among young people. Nearly 70% of the population has been fully vaccinated.
Dr. Kazuhiro Tatta, a professor of virology at Toho University, said that "rapid and intense vaccinations in Japan for those under 64 may have created a temporary condition comparable to herd-immunity."
Tateda observed that vaccination rates rose in July and September as the more dangerous delta variant spread fast.
However, he cautioned that the U.S., Britain, and other countries where inoculations started months earlier than in Japan showed that vaccines are not perfect and that efficacy slowly wears off.
Japan began its vaccinations in February, with elderly and health workers being the first to receive them. Despite the shortage of vaccines imported, progress was slow until May when supplies stabilized. Daily inoculation targets were increased to more than 1 million to ensure protection against the July 23-August 8 Olympics.
The daily doses of vaccines rose to 1.5 million in July. This pushed vaccination rates up from 15% in early juillet to 65% in October. It was higher than the 57% in the United States.
Just weeks before the Olympics, daily new cases rose dramatically. Japan was forced to host the Games with more than 5,000 cases in Tokyo each day and around 20,000 across the country in the early part of August. Tokyo had 40 cases on Sunday. This is below 100 cases for the ninth consecutive day, and it was also the lowest number this year. Japan reported 429 cases Sunday, a nation-wide total of approximately 1.71 million cases and 18,000 deaths since last year's pandemic.