July 31, 2023
Keio University
In a joint study with Professor Ilan Noy of Victoria University of Wellington, New Zealand, and Professor Eric Strobl of the University of Bern, Switzerland, Professor Toshihiro Okubo of the Faculty of Economics, Keio University, has quantitatively clarified the effects on economic activity and the effectiveness of non-pharmaceutical interventions (NPIs) during the 1918–1920 influenza pandemic, the so-called "Spanish flu," using prefectural data from Japan.
The results show that while deaths from the Spanish flu, as measured by excess mortality, had a negative impact on economic activity, non-pharmaceutical interventions (NPIs), such as calls for thorough implementation of preventive measures conducted in various regions, mitigated this negative economic impact by about 20–30%. It was found that rather than a choice between economic activity and infectious disease control, NPIs protect lives while also mitigating the decline in economic activity by maintaining employment. The findings of this research were published in the international peer-reviewed journal "Journal of Regional Science."
Key Points of This Research
Measuring excess mortality by prefecture revealed significant differences. Two high peaks were observed, mainly in urban areas. In many prefectures, the first wave was significantly higher than the second, but the opposite pattern was observed in some prefectures.
Various campaigns were conducted, including the distribution of pamphlets on infection prevention measures, posters and signs on the streets, the creation of portable cards and slogans, announcements in movie theaters, and awareness-raising activities in schools and workplaces. Although all prefectures implemented some measures, the degree of thoroughness, methods, and timing varied by prefecture and were not uniform. Many prefectures placed more emphasis on slogans, clarity, and ease of implementation rather than on disseminating and enforcing preventive guidelines through distribution or education.
Using spatial econometric methods, the study estimated the impact on the growth of the textile industry, which was a major industry at the time. Excess mortality had a negative impact, significantly reducing employment and production value. However, a stronger degree of non-pharmaceutical intervention had the effect of offsetting this negative impact by about 20–30% (around the mean value of excess mortality).
Furthermore, a case study was conducted on Kochi Prefecture. With the cooperation of The Kochi Shimbun, and based on newspaper articles from the time, the study clarified how NPIs specifically affected people's lives, what measures local assemblies and administrations implemented, and how they made requests to factories within the prefecture, affecting manufacturing production.
For the full press release, please see below.