Impact of weather factors on Mycoplasma pneumoniae pneumonia
- 1Department of Planning Information and Administration, Fukuoka Institute of Health and Environmental Sciences, Dazaifu-shi, Fukuoka, Japan
- 2Department of International Health, Institute of Tropical Medicine, Nagasaki University, Nagasaki-shi, Nagasaki, Japan
- 3Department of Health Services Management and Policy, Kyushu University Graduate School of Medicine, Higashi-ku, Fukuoka, Japan
- Dr D Onozuka, Department of Planning Information and Administration, Fukuoka Institute of Health and Environmental Sciences, 39 Mukaizano, Dazaifu-shi, Fukuoka 818-0135, Japan;
- Received 16 November 2008
- Accepted 12 March 2009
- Published Online First 23 March 2009
Background: Although multiple combinations of weather factors may contribute to an increased incidence of Mycoplasma pneumoniae pneumonia, few studies have investigated the association between weather factors and cases of M pneumoniae pneumonia.
Methods: Data on cases of M pneumoniae pneumonia and weather factors in Fukuoka, Japan from 1999 to 2007 were obtained and time-series analysis was used to assess the effects of weather variables on M pneumoniae pneumonia cases, adjusting for confounding factors. A total of 13 056 M pneumoniae pneumonia cases were reported during the 9-year study period, of which 12 234 (93.7%) were under 15 years of age.
Results: The weekly number of M pneumoniae pneumonia cases increased by 16.9% (95% CI 11.3% to 22.8%) for every 1°C increase in the average temperature and by 4.1% (95% CI 2.7% to 5.5%) for every 1% increase in relative humidity.
Conclusions: From 1999 to 2007, cases of M pneumoniae pneumonia increased significantly with increased average temperature and relative humidity in Fukuoka, Japan.
Competing interests: None.
Funding: The study was supported in part by a Grant-in-Aid for Scientific Research from the Ministry of Health, Labour and Welfare, Japan.
▸ Additional figures are published online only at http://thorax.bmj.com/content/vol64/issue6