Public health and multiple-phase mortality decline: Evidence from industrializing Japan

A fuzzy inference-based index for piped water supply service quality in a complex, low-income urban setting

Sustainable Development Goal (SDG) 6 calls for universal access to safely managed drinking water services. We studied the evolution of the water supply service between January 2017 and December 2021 in the town of Uvira (South Kivu, Democratic Republic of the Congo) where large investments were made to improve the water supply infrastructure during this period, including a new 2,000-m3 tank, 56 community taps and 1,191 private taps. Across 16 geographic clusters in the town, we assessed water service accessibility, water quantity, continuity, and affordability, based on data provided by the construction team and the utility. We combined these dimensions into a single index ranging 0-100% according to rules defined using the fuzzy inference Mamdani method. Our results show that despite substantial increases in accessibility (i.e. proportion of households with a private tap or within 200 m of a community tap), overall service quality remained unsatisfactory, with a maximum index value of 38.1%, and worsened in many parts of the town due to limitations of the water production capacity after major flooding events and persistent electricity supply issues. The estimated amount of water supplied per user per day remained under 20 L during >95% of the observation period, with a decreasing trend. Pumps operated 58% of the time on average and the frequency of days without electricity supply increased over time. Our study highlights the important gap between upgrades in water supply infrastructure and improvements in the quality of service. The analysis of potential future scenarios for Uvira indicates that increasing production capacity is priority to improve overall service quality. Our results demonstrate that meeting SDG6 will be challenging in complex urban settings and will not only require sustained investments in water supply infrastructure but also in systems management and in energy supply.

The long-run heterogeneous effects of a cholera pandemic on stature: Evidence from industrializing Japan

The recent COVID-19 pandemic poses the general question on how infectious diseases can persistently affect human health. A growing body of literature has found a significant amount of evidence on the long-term adverse effects of infectious diseases, such as influenza, typhoid fever, and yellow fever. However, we must be careful about the fact that little is known about the long-term consequences of the acute diarrheal disease pandemic cholera - Vibrio cholerae bacillus - which still threatens the health of the population in many developing countries. To bridge this gap in the body of knowledge, we utilized unique census-based data on army height at age 20 in early 20th-century Japan, with a difference-in-differences estimation strategy using regional variation in the intensity of cholera pandemics. We found that early-life exposure to a cholera pandemic had heterogeneous stunting effects on the final height of men; the magnitude of the stunting effects increased as the intensity of exposure increased.

Analysis of Environmental Activities for Developing Public Health Investments and Policies: A Comparative Study with Structure Equation and Interval Type 2 Fuzzy Hybrid Models

The design of elements which exert pivotal effects on leisurely physical activity (LPA) in open space is an important part of urban development. However, little research has been done about the influence and discrepancies of those elements in different types of open space. To research these issues and to guide the design of urban open space, a survey from 8 open spaces (2 curtilage, 2 neighborhood squares (NS), 2 parks, and 2 campus) is conducted and a questionnaire is administered. Simultaneous analysis of several groups (SASG) of Structure equation model (SEM) is used, and the effects and discrepancies are acquired. In addition to this situation, interval type 2 (IT2) fuzzy hybrid decision making model is proposed in the second analysis. In this framework, IT2 fuzzy decision-making trial, evaluation laboratory (DEMATEL), and IT2 fuzzy technique for order preference by similarity to ideal solution (TOPSIS) methods are used. The results show that the influence relationships between elements and LPA did exist in four groups. Another important conclusion is that there were discrepancies of influence among different space groups. Physical environment (PE) has the greatest influence on LPA in the curtilage, whereas facilities exert the most effect in NS group. Additionally, amenities only have significant impact in parks and facilities only exercise remarkable influence on duration on campus. In addition to them, it is also identified that key design elements are presented for different types of space and that design strategy is provided through 4 specific examples.

Chain effects of clean water: The Mills-Reincke phenomenon in early 20th-century Japan

This study explores the validity of chain effects of clean water, which are known as the "Mills-Reincke phenomenon," in early 20-century Japan. Recent studies have reported that water purifications systems are responsible for huge contributions to human capital. Although some studies have investigated the instantaneous effects of water-supply systems in pre-war Japan, little is known about the chain effects of these systems. By analyzing city-level cause-specific mortality data from 1922 to 1940, we find that a decline in typhoid deaths by one per 1000 people decreased the risk of death due to non-waterborne diseases such as tuberculosis and pneumonia by 0.742-2.942 per 1000 people. Our finding suggests that the observed Mills-Reincke phenomenon could have resulted in the relatively rapid decline in the mortality rate in early 20-century Japan.

Early-life exposure to weather shocks and child height: Evidence from industrializing Japan

In this study, we estimate the long-run effects of early-life exposure to weather shocks on the height of primary school children. To estimate the global impacts on almost the entire child population in an industrializing country, we utilize both a unique nationwide multi-dimensional longitudinal dataset of Japanese children aged 6-11 and official monthly statistics on meteorological conditions in the 1920s. We observe that the exposure to cold waves in early-life exerted stunting effects on both the boys and girls. In the coldest regions in the northeastern area of Japan, the stunting effects of cold weather shocks on the boys and girls are estimated to be approximately 0.8 and 0.6 cm, respectively. Our observation indicates that prenatal (postnatal) exposure is important for the boys (girls). Our results suggest that the marginal effects of cold waves are stronger in the warmer regions than in the colder regions.