On February 17, 2022, Malawi declared the outbreak of a polio case of a three-year-old girl as the first case in five years in the “polio-free” African continent. In the middle of the COVID-19 pandemic, we tend to forget about other infectious diseases, including polio, but the significance of routine vaccination should not be forgotten even in the pandemic period. Poliomyelitis (polio) is an infectious disease that seriously affects children under five years old. The virus invades the nervous system and may cause eternal paralysis of arms and legs to children. Human beings have suffered from polio since ancient times as illustrated in Pharaonic inscriptions in Egypt.
It is widely known that polio is a “preventable” disease, but it is not necessarily widely recognized that polio is an “incurable” disease for human beings at this stage. According to the Japanese Ministry of Health, Labour and Welfare (MHLW), children (basically from three-month-old to twelve-month-old infants) in Japan are supposed to be vaccinated three times, and an additional fourth dose is available afterwards. Most Japanese people have taken the routine poliovirus vaccination for granted, but the Japanese people suffered from an outbreak of polio in the past, and the response and crisis management of the polio endemic has profound implications for the current coronavirus pandemic and Japan’s vaccine diplomacy.
Polio Outbreaks, Vaccine Imports, and Routine Vaccination in Japan
Historically, occasional polio outbreaks in Japan became discernible after the termination of its isolationist foreign policy, namely the national seclusion policy. The cycle of the outbreaks of polio occurred in the 1910s, the 1920s, and the 1930s. In postwar Japan, a serious spread of polio occurred in Aomori in 1948. The annual occurrence of polio cases between 1948 and 1959 was approximately 2,000 to 3,000 on average. In 1960, another outbreak of polio occurred in Hokkaido, and the number of polio cases mounted to 5,606, marking the worst record in Japan. Outraged mothers, who were concerned about the health condition of their children, protested on the streets and besieged the Health and Welfare Ministry which was reluctant to import poliovirus vaccines, especially due to the lack of sufficient clinical evidence of possible side-effects.
In June 1961, the Japanese government eventually decided to import oral poliovirus vaccines (OPV) mostly from the Soviet Union and partly from Canada, and mass vaccination was implemented in Japan despite the existence of concerns about side-effects. Notably, Health and Welfare Minister Furui Yoshimi stated that he would take all responsibilities for the decision on the emergency import and mass vaccination in Japan. It is estimated that 13 million doses from the Soviet Union saved over 20 million Japanese children. This was an unusual case of international cooperation between Tokyo and Moscow in the Cold War, but it was a result of the normalization of the bilateral diplomatic ties based on the Joint Declaration between Japan and the Soviet Union in 1956. During the 1960s, the number of polio patients drastically decreased owing to the mass vaccination. As a result of the poliovirus control based on OPV, wild-type polio cases have never been reported since 1980 in Japan.
Although routine vaccination of OPV was implemented and the elimination of wild poliovirus was achieved in Japan, polio cases among OPV recipients as vaccine-associated paralytic poliomyelitis (VAPP) continued to be reported every year, with the most in 2011. According to a survey in Kanagawa, most parents replied that they thought OPV was dangerous and desired their children to take inactivated poliovirus vaccine (IPV). The Japan Pediatric Society advised that children should take OPV until domestically produced IPV could be available. On the contrary, the World Health Organization (WHO) recommended that OPV should be replaced with IPV in countries that had achieved the poliovirus elimination. Japan was one of the few industrialized countries that used OPV even after the elimination of poliovirus in the country, and the Japanese public strongly demanded that the government replace OPV with IPV for domestic routine vaccination. This was finally done in 2012.
The Global Polio Eradication Initiative and Japan’s Contributions
In the meanwhile, Rotary International began its fight against polio by initiating a multi-year project to immunize six million children in the Philippines in 1979, and launched the first and largest internationally coordinated poliovirus eradication project, namely “PolioPlus” with an initial fundraising target of $120 million in 1985. In 1988, the World Health Assembly of the WHO adopted a resolution to launch a public-private partnership, the Global Polio Eradication Initiative (GPEI), with international support by the WHO, Rotary International, the U.S. Centers for Disease Control and Prevention (CDC), and the United Nations Children’s Fund (UNICEF). The Bill & Melinda Gates Foundation (the Gates Foundation) and Gavi, the Vaccine Alliance, later join the GPEI. The Japanese government made financial contributions toward polio eradication in cooperation with these international organizations and the civil society.
Being encouraged by the global polio eradication movement, a non-partisan parliamentary association, the Diet Task Force on Global Polio Eradication, was established in Japan in May 2011. In August of the year, the Japanese government decided to initiate a poliovirus vaccination project as part of its official development assistance (ODA) to Pakistan by financing some five billion yen in cooperation with the Gates Foundation. The polio eradication project was implemented by a loan conversion method, and the Gates Foundation agreed to repay the entire debt for Japan’s ODA loan in place of the Pakistani government. In September 2014, the Japan International Cooperation Agency (JICA) and the Gates Foundation agreed on another loan conversion contract to finance some eight billion yen for polio eradication in Nigeria.
The epoch-making loan conversion method can be regarded as an integral part of Japan’s global health policy, and it is observed that the polio immunization program in Nigeria contributed to polio eradication in Africa. In July 2015, the Diet Task Force on Global Polio Eradication submitted a “resolution to support polio eradication for children in the world” to then Vice-Foreign Minister Nakayama Yasuhide. Since then, Tokyo has made financial contributions including grant aid assistance to polio vaccination programs led by the UNICEF in Afghanistan, Pakistan, Nigeria, and the Lake Chad region.
Significance of Vaccine Diplomacy toward a “Polio-Free” World
Through the endeavor of the polio vaccination program within the framework of the GPEI, it was confirmed in 2019 that there had been no polio cases in Nigeria for three years, and the WHO declared in August 2020 that wild poliovirus had been eradicated in Africa. After the declaration of the polio-free African continent, Afghanistan and Pakistan are the last two remaining countries as the final poliovirus bastions, where wild poliovirus still existed. In February 2022 however, the WHO declared a wild poliovirus case was identified in a three-year-old girl in Malawi as mentioned before. The strain found in the Malawian girl reportedly stemmed from Pakistan, and this incident indicates the difficulty in preventing the cross-border spread of poliovirus. The case in Malawi also suggests that any countries including Japan could have a new polio case owing to globalization.
In the middle of the COVID-19 pandemic, the number of children who took routine vaccinations decreased in Japan and the world. In fact, the WHO and the CDC warned that the largest decrease was in the number of children vaccinated for measles during the pandemic period. In the case of polio vaccination, it is necessary for children to take vaccine shots several times for sufficient immunization. As mentioned earlier, children in Japan are allowed to take IPV four times in total, but children in some European countries including the United Kingdom, Germany, and France, are supposed to take five doses of polio vaccines.
Since possibilities of re-outbreak of poliovirus in Japan, stemming from unvaccinated people overseas, cannot be ruled out, an additional fifth dose of IPV may be necessary for children in Japan as deliberated in the MHLW and encouraged by some requests from the private sector. By implementing proper routine polio vaccination with IPV, Japan can save the lives of children in the country. At the event of the Eighth Tokyo International Conference on African Development (TICAD 8) to be held in Tunisia on August 27 and 28, 2022, the Kishida administration is expected to make further diplomatic and financial contributions to making the African continent “polio-free” again and facilitating the achievement of a “polio-free world” in the midst of the COVID-19 pandemic.