Correlation between infectious disease and soil radiation in Japan: An exploratory study using national sentinel surveillance data

S. Inaida, Toshihide Tsuda, S. Matsuno

Research output: Contribution to journalArticle


We investigated the relationship between epidemics and soil radiation through an exploratory study using sentinel surveillance data (individuals aged <20 years) during the last three epidemic seasons of influenza and norovirus in Japan. We used a spatial analysis method of a geographical information system (GIS). We mapped the epidemic spreading patterns from sentinel incidence rates. We calculated the average soil radiation [dm (μGy/h)] for each sentinel site using data on uranium, thorium, and potassium oxide in the soil and examined the incidence rate in units of 0·01 μGy/h. The correlations between the incidence rate and the average soil radiation were assessed. Epidemic clusters of influenza and norovirus infections were observed in areas with relatively high radiation exposure. A positive correlation was detected between the average incidence rate and radiation dose, at r = 0·61-0·84 (P < 0·01) for influenza infections and r = 0·61-0·72 (P < 0·01) for norovirus infections. An increase in the incidence rate was found between areas with radiation exposure of 0 < dm < 0·01 and 0·15 ≤ dm < 0·16, at 1·80 [95% confidence interval (CI) 1·47-2·12] times higher for influenza infection and 2·07 (95% CI 1·53-2·61) times higher for norovirus infection. Our results suggest a potential association between decreased immunity and irradiation because of soil radiation. Further studies on immunity in these epidemic-prone areas are desirable.

Original languageEnglish
Pages (from-to)1183-1192
Number of pages10
JournalEpidemiology and Infection
Issue number6
Publication statusPublished - Apr 1 2017



  • Epidemic
  • geographical information system (GIS)
  • influenza
  • national sentinel surveillance
  • norovirus
  • soil radiation

ASJC Scopus subject areas

  • Epidemiology
  • Infectious Diseases

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