Epidemiology and Infection

Original Papers

Weather and infection

Association of haemorrhagic fever with renal syndrome and weather factors in Junan County, China: a case-crossover study

J. LIUa1a2 c1, F. Z. XUEa1, J. Z. WANGa1 and Q. Y. LIUa2a3

a1 Institute of Epidemiology and Biostatistics, School of Public Health, Shandong University, Jinan, China

a2 Shandong University Climate Change and Health Center, Jinan, China

a3 State Key Laboratory for Infectious Diseases Prevention and Control, National Institute for Communicable Disease Control and Prevention, China CDC, Beijing, China


Haemorrhagic fever with renal syndrome (HFRS) is a type of vector-borne zoonosis sensitive to climate change. To explore the short-term effect of air temperature and amount of precipitation on HFRS incidence, a total of 13 722 clinically confirmed HFRS cases from January 1977 to December 2001 in Junan County, China were included in this study. According to symmetric bidirectional case-crossover design, the hazard period (the three calendar months preceding the month when the case was diagnosed) and the control period (the same calendar month of the year before and the year after the hazard period) matched and conditional logistic regression was used to examine the effect of monthly mean temperature and precipitation on the risk of HFRS. The results showed the facilitating climatic conditions for HFRS included: condition with moderate mean air temperature (10–25 °C) and abundant precipitation (>120 mm) 3 months before [odds ratio (OR) 1·346, 95% confidence interval (CI) 1·191–1·522] and 2 months before (OR 1·193, 95% CI 1·063–1·339); and condition with temperature >25 °C and abundant precipitation (>120 mm) 3 months before (OR 1·17, 95% CI 1·004–1·363). Temperature of 10–25 °C and moderate precipitation (10–120 mm) in the current month was the most favourable condition for HFRS incidence.

(Received October 24 2011)

(Revised January 21 2012)

(Accepted June 08 2012)

(Online publication July 16 2012)

Key words

  • Amount of precipitation;
  • atmospheric temperature;
  • case-crossover study;
  • haemorrhagic fever with renal syndrome