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Mortality in the 2011 tsunami in Japan
Shinji Nakahara1, Masao Ichikawa
1Department of Epidemiology and Health Promotion, St. Mariana University, Kawasaki, Kanagawa, Japan. snakahara-tky@umin.net
Journal of Epidemiology
|October 24, 2012
Summary
The 2011 Japan tsunami caused widespread deaths. Mortality increased with age, with no sex differences, but school-aged children had lower mortality in Iwate, contrasting with higher rates in other regions.
Area of Science:
- Disaster medicine
- Public health
- Epidemiology
Background:
- The 2011 Great East Japan Earthquake and tsunami resulted in approximately 20,000 fatalities.
- This study focuses on mortality patterns in the three most impacted prefectures: Iwate, Miyagi, and Fukushima.
Purpose of the Study:
- To analyze mortality patterns by age, sex, and region following the 2011 tsunami.
- To compare regional variations in mortality rates across different age groups.
Main Methods:
- Utilized police data of earthquake victims from Iwate, Miyagi, and Fukushima prefectures.
- Calculated mortality rates stratified by sex, age group, and region.
- Employed rate ratios (RRs) to compare regional mortality variability, using Iwate as the reference.
Main Results:
- Mortality rates consistently increased with age across all studied regions.
- No significant differences in mortality were observed between sexes.
- School-aged children exhibited notably lower mortality in Iwate compared to other age groups.
- Conversely, northern Miyagi and southern areas showed higher RRs for school-aged children.
Conclusions:
- The study identified distinct regional mortality patterns, particularly concerning school-aged children.
- The underlying reasons for these observed mortality patterns and regional disparities remain unaddressed.
- Further research is recommended to investigate the causes of these differences to enhance disaster preparedness policies.
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