The historical legacy of Nagayo Sensai and the Japanese hygienic practice and mentality of “eisei” illustrates the importance of non-pharmaceutical interventions and the necessity of establishing a strong local public health infrastructure for managing COVID-19.  This article was originally published in Pandemic Discourses. 

Over the past year, many observers have referred to the relative success in the Asia-Pacific region in controlling the COVID-19 pandemic, keeping “their economies afloat and avoid longer, harsh lockdown measures”, attributing it largely to “the urgent action taken by many Asia–Pacific jurisdictions to eliminate community transmission through a series of non-pharmaceutical interventions”. Up until the availability of vaccines, the only means of protecting one’s self from infection was non-pharmaceutical interventions, i.e., hand-washing, disinfecting, social distancing, ensuring good ventilation, wearing face-masks, and such.  Japan, and other East Asian societies, whose social norms were more receptive to such measures of self-regulation, came out well in holding down infections. Conversely, societies that had come to rely almost exclusively on pharmaceutical solutions to medical problems had greater difficulties in convincing their citizens to practice such measures, thus taking longer to control the rapid spread, and experiencing repeated peaks.

In this context, Nagayo Sensai (1838-1902), often referred to as the “father of public health” in Japan, frequently came to mind, and I shall explain the link.

Nagayo Sensai was an early Meiji Era (1868-1912) statesman, doctor and educator, born into a family of physicians of the samurai class which had for generations been practicing traditional Chinese medicine. Living close to Nagasaki, the only port open to foreign trade, culture and sciences during Japan’s lengthy isolation, his grandfather, Nagayo Shuntatsu, encountered Western medicine and became convinced of its superiority. Shuntatsu was also one of the pioneers in practicing community-wide smallpox inoculation, using imported cowpox vaccines.  Smallpox was the most dreaded of diseases at that time. Shuntatsu groomed young Sensai as his successor, ensuring him the best classic education and medical training possible, and the latter imbibed Shuntatsu’s thirst for Western medicine, his humanitarian attitude towards serving the community, and the appreciation for preventing diseases where possible.

Sensai came of age during a period of great turmoil in Japan, when the Meiji Restoration (1868) ended some 250 hundred years of isolation and feudal rule by the Tokugawa Shogunate, and a centralized, unified state was established in the new capital, Tokyo.  He joined thousands of other bright and ambitious youths converging on Tokyo, aspiring to serve the country and contribute to nation building.

These were his “eureka moments,” which enabled Sensai to grasp the concept of public hygiene/health, namely, that modern societies established governance structures and systems, at central and local levels, which strove to ensure better health outcomes of the entire population by protecting and improving lives. Measures included not only medicine, but water supply and sewerage, treatment of waste, control of foodstuffs, and improving the living conditions of the poor. Underpinning all efforts was the recording of statistics on birth and deaths.

Once in Tokyo, Sensai benefitted from two early opportunities to observe what was happening in the wider world. Firstly as a member of the Iwakura mission of 1871, the “Mother of All Study Tours,” in which over a hundred of the senior-most politicians, bureaucrats, nobles, and experts toured the United States and Europe for 18 months in order to absorb whatever was critical for the establishment of a wealthy and powerful modern state.  Sensai’s role was to learn about medical systems. His second exposure was a visit to the United State’s in 1876 for the Great Exhibition of Philadelphia that was combined with a tour of several cities. These were his “eureka moments,” which enabled Sensai to grasp the concept of public hygiene/health, namely, that modern societies established governance structures and systems, at central and local levels, which strove to ensure better health outcomes of the entire population by protecting and improving lives. Measures included not only medicine, but water supply and sewerage, treatment of waste, control of foodstuffs, and improving the living conditions of the poor. Underpinning all efforts was the recording of statistics on birth and deaths. This realization was revolutionary in early Meiji Japan.

To encapsulate his new understanding, he applied a term taken from classic Taoism, “eisei”(衛生 hygiene, or more literally,  to protect life).  Sensai perceived eisei as a key element of modernizing Japan and becoming a wealthy and powerful nation. Accordingly, he established the Eisei Kyoku (Public Health Bureau) in the Ministry of Home Affairs, becoming its director-general.

One of the first acts of the Eisei Bureau was the issuance of a Vaccination Proclamation for Smallpox (1875) which made Jennerian vaccination the only legal way of protection against smallpox, to be given free to all infants, requiring all prefectures to report twice yearly on numbers vaccinated. Though visionary, in practice, given the weak infrastructure, lack of vaccines and need to establish an entirely new reporting system where none existed, progress was only gradual, with smallpox persisting into the 20th century. However, the smallpox vaccination system was the first preventive health activity targeted towards total outreach, with a recording and reporting system that became a prototype for all reporting of epidemics.

Sensai considered it critical for the citizenry to understand and internalize the concept of eisei, so that they are persuaded to practice hygienic measures. For this purpose, he promoted the establishment of private/public Eisei Associations, which gradually reached out to the general public promoting eisei thinking and practice.

Sensai recognized the need to involve local governments to tailor activities according to local circumstances and to bring services as close to the community as possible, therefore appointing eisei officials at the local levels (patchily).  Furthermore, Sensai considered it critical for the citizenry to understand and internalize the concept of eisei, so that they are persuaded to practice hygienic measures. For this purpose, he promoted the establishment of private/public Eisei Associations, which gradually reached out to the general public promoting eisei thinking and practice.

The greatest challenge for Sensai and the Eisei Bureau was probably the waves of cholera epidemics that swept Japan. Given Japan’s isolationist policy before the Meiji era, Japan had been spared, in the main, of earlier epidemics of cholera, and thus the populace had limited immunity.  But being aware of the devastating consequences of cholera suffered by neighboring countries, in 1876, the Eisei Bureau issued the Cholera Act, requiring all personnel and goods on ships landing in Japan from countries with cholera epidemics to be inspected before being discharged.  Notwithstanding, in 1877 and in 1879, a British and then a German ship arrived with crew and cargo from China where cholera was rampant, and in both cases these imperial powers claimed extraterritoriality and broke the quarantine law, landing crew and cargo into Japanese ports without inspection. Japan had signed unequal treaties with both European imperials powers earlier and remained powerless. These incidents contributed significantly to the nationwide spread of cholera, resulting in 163,000 cases of cholera, with a high case fatality of 65% (1879/80).  Impressively detailed statistics remain, as Sensai had learnt from Snow and Chadwick in the UK and other pioneers of public health, the critical importance of statistics to convince decision makers.

Unfortunately, Sensai’s nascent public health infrastructure was near powerless to fight back the cholera epidemics. Thus, the police system increasingly took over, forcefully registering and quarantining the infected outside their communities under appalling conditions, publicly identifying (and shaming) families with patients, relentlessly disinfecting houses, severing transport links with affected communities and so forth, and the harsh measures resulted in negative backlash from the public. Even the term eisei began to be looked at with aversion. Sensai regarded this as his greatest setback.

In sum, Sensai’s contribution was in setting up a rudimentary public health infrastructure based on what he had absorbed in Europe and the United State’s, and linking it with the classic, samurai philosophy of self-regulation, namely, eisei. Despite challenges, the concept of eisei somehow prevailed, becoming well-established among Japanese, to the extent that googling “eisei X corona” in Japanese as of mid-February 2021 produced some 137 million hits.

I shall conclude with some possible lessons for the COVID-19 pandemic relating to Sensai’s eisei work and thinking.

Sensai had recognized and emphasized the critical need for public health administration at the local level. One key factor in effectively controlling the rapid spread of the pandemic in Japan early on was the key role played by ward-level health offices (lowest administrative level) in tracking, tracing and informing all possible contacts. This also resulted in huge administrative overload during the second epidemic in winter 2020/21. In contrast, while Denmark continues to rank among the leading countries in testing (nearly hundred thousand tests a day), the follow up to the tests, i.e., contact tracing and isolation,  has been less consistent, as it is the responsibility of the central Danish Patient Safety Authority. The involvement of administrative level closest to citizens, the communes, remaining arbitrary.  In addition, reflective of Danish social norms, much of the initiative in undergoing quarantine and informing contacts has been left to the infected individual. Much to the critique of observers and especially in light of the current spread of the English variant, this has resulted in 1.7 near contacts being contacted by infected individuals themselves, while only 0.8 are contacted by the Patient Authority (as of February 19th, 2021). Looking to the future, more analysis is needed to conclude which mix of strategies are most appropriate for varying administrative structures and social norms.

Sensai’s negative experience with cholera demonstrates the critical importance of quarantine at the national border in controlling epidemics.  In the current pandemic, successful countries instituted tough and effective early quarantine measures, preventing later waves of COVID-19.  Unfortunately, there are countless examples around the world of travelers ignoring guidelines and bringing in infections. The rapid spread of the new variants from UK, South Africa, and Brazil, point to continuing threats and the continued need for quarantine. As of mid-February, 2021, the UK is finally bringing in a much tougher quarantine regime requiring all travelers from COVID-19 hotspots to undergo a ten-day hotel quarantine at their own expense, after long and devastatingly high levels of infections with some 60,000 daily new infections at its peak.

Most importantly, Sensai’s legacy is about the need for internalizing eisei message and practice among citizenry, so they can protect themselves and their families.

Most importantly, Sensai’s legacy is about the need for internalizing eisei message and practice among citizenry, so they can protect themselves and their families. Sensai’s unfortunate experience with cholera where the damage caused by drastic police enforcement measures required decades to overcome and for eisei thinking and practice to take root. Currently, in Denmark, there is a raging debate about the government’s attempt to pass a new Epidemic Law which includes a list of enforcement measures and sanctions which many Danes with their more liberal individualist values have difficulty accepting.

The world simply cannot afford to repeatedly pay the price in lives and livelihoods, especially in the poorest countries. And in all future pandemics, the first line of defense will continue to be eisei.

Given the increasingly globalized world with porous borders that we live in, the inherent nature of viruses to mutate, and the longer term near-certainty of other zoonotic diseases emerging due to climate change and population pressures that lead to increased human/animals contacts, the current pandemic is demonstrating the need for far more effective and efficient means to fight future epidemics and pandemics. The world simply cannot afford to repeatedly pay the price in lives and livelihoods, especially in the poorest countries. And in all future pandemics, the first line of defense will continue to be eisei.

Eimi Watanabe has had a long career with UNICEF and UNDP, with her final post as Assistant Secretary General and Director, Bureau for Development Policy as well as serving as the Chair for the World Bank Inspection Panel.  She was born in Japan and received a PhD in Sociology from London School of Economics. She currently lives in Denmark.