Six waves of COVID-19 were conducted in Japan. The number of deaths and cases per capita was significantly lower than other G7 countries. This is despite Japan having the oldest population in the world and densely populated. Japan is known for its high rates of vaccination, particularly among older people. Masking is also a common practice. However, neither of these are a complete explanation. Even before the advent of vaccines, deaths were low in Asia. Masks are widespread throughout Asia.

Japan sought to understand the spread of the disease, and how to minimize deaths and hospitalizations. It also tried to maintain social and economic activities. Uneasy trade-offs between these factors can occur. Social pressure was likely to have boosted protective measures like mask wearing and reduced risky behaviors. The government provided its citizens with the information they needed to take preventive action, and did not give any rigid prescriptions.

When the severe acute respiratory syndrome (SARS), which was a result of a coronavirus infection in China, broke out, I was the WHO’s Western Pacific regional officer for emerging diseases. It was contained in eight months and there were less than 1,000 people who died. When I was first informed that a coronavirus similar to SARS-CoV-2 had been identified in China among people suffering from pneumonia, I assumed the outbreak would follow a similar pattern.

It was then that I realized the truth. SARS was a severe illness that affected most people. COVID-19 is milder and asymptomatic. People can also spread the disease, which is unlike SARS. COVID-19, on the other hand, is much less visible and therefore harder to control.

Japan’s constitution forbids tight lockdowns. Therefore, another strategy was required to stop transmission. Japan had over 8,000 public-health nurses in 400 public-health centers. They were conducting retrospective contact tracing for diseases such as tuberculosis to determine how people became infected. This system was quickly modified to COVID-19.

Scientists had discovered many transmission clusters by February 2020. They realized that the majority of infected persons did not infect others, but that a few people infected many. My previous work has shown me that respiratory viruses are transmitted mainly by aerosols. To create a better public-health message, my colleagues and I searched for common risk factors in superspreading events. This message included early signs that SARS-CoV-2 could spread via aerosols.

We were prompted to warn about the “3Cs” (sanmitsu), which are closed environments, crowded areas and close-contact settings. Japan encouraged this concept heavily, even though other countries were focusing on disinfection. It asked people to avoid high-risk activities like nightclubs, karaoke bars and indoor dining. The majority of people complied. An international panel of journalists, academics, and artists named sanmitsu Japan the buzzword for 2020.

We have been tracking the evolution of superspreading events since the outbreak of the pandemic. Others around the globe have tried to ‘go back to normal’ and lifted all restrictions. However, cases continue to rise, leading to significant deaths. While simple solutions can be used to benefit the wealthy and the immunocompetent, vulnerable people are still being impacted by such policies. According to current data, Japanese citizens are adapting. Japan celebrated its Golden Week holidays in late April and early mai. There were no restrictions this year on the hours restaurants could close and whether alcohol was allowed in them. Although crowds were higher than usual, they were still smaller than the years prior to the pandemic. Therefore, precautions such as the need for ventilated areas and closing restaurants at specific times were important. People would often relax when the cases receded, which led to a subsequent wave. Despite no restrictions, the behavior after the surge this year is quite different.

This situation is getting more complex. Because Omicron fatality rates and vaccine coverage are low, people are reluctant to take strict measures, even when there is an increase in cases. In Japan, a country with high income, there are many interventions that can be used, including booster vaccinations, antivirals and better clinical care. There are also public-health measures such as CO2 monitors for monitoring ventilation in public buildings.

There is no single solution that will eliminate the virus. Japan’s response to the virus has been criticized for not being perfect. Although the initial testing capabilities of Japan were limited, extensive testing was not sufficient to stop transmission.

Scientists and government advisors must accept the fact that the ideal balance is not yet known. They need to understand that both the behavior of the virus and the people it infects is susceptible to change, and adapt their recommendations accordingly.

People long for the days before this virus. We are far from normal. The best balance must be found between transmission suppression and maintaining economic and social activities. How? To minimize suffering around the world, we must use all of the tools available to us, as they relate to our cultures, traditions, legal frameworks, and current practices.