title: Investigating the effects of climatic variables and reservoir on the incidence of hemorrhagic fever with renal syndrome in Huludao City, China: a 17-year data analysis based on structure equation model.
abstract: BACKGROUND
  HFRS is a serious public health problem in China and the study on HFRS is important in China for its large population. The present study aimed to explore the impact of climatic variables and reservoir on the incidence of HFRS in Huludao City, an epidemic focus of the disease in northeastern China.
  
  
  METHODS
  Structure Equation Model (SEM), a statistical technique for testing and estimating causal relationships, was conducted based on climatic variables, virus-carrying index among rodents, and incidence of HFRS in the city during the period 1990 to 2006. The linear structural relationships (LISREL) software (Scientific Software International, Lincolnwood, IL) was used to fit SEMs.
  
  
  RESULTS
  Temperature, precipitation, relative humidity and virus-carrying index among rodents have shown positive correlations with the monthly incidence of HFRS, while air pressure had a negative correlation with the incidence. The best-fit SEM model fitted well with the data-based correlation matrix, P value was more than 0.56, root mean square error of approximation (RMSEA) equaled to 0, goodness-of-fit index (GFI) was more than 0.99.
  
  
  CONCLUSIONS
  Climate and reservoirs have affected the incidence of HFRS in Huludao City, located in northeastern China. Climate affects HFRS incidence mainly through the effect on reservoir in the study area. HFRS prevention and control should give more consideration to rodent control and climate variations.
authors: Department of Epidemiology, School of Public Health, China Medical University, Shenyang, PR China. pguan@mail.cmu.edu.cn
authors: Peng
authors: P
authors: Guan
authors: Desheng
authors: D
authors: Huang
authors: Miao
authors: M
authors: He
authors: Tiefeng
authors: T
authors: Shen
authors: Junqiao
authors: J
authors: Guo
authors: Baosen
authors: B
authors: Zhou
mesh_terms: D000818:Animals; D002681:China / Q000453:epidemiology; D002980:Climate; D004197:Disease Reservoirs / Q000706:statistics & numerical data / Q000821:virology*; D018063:Hantaan virus; D006480:Hemorrhagic Fever with Renal Syndrome / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D051379:Mice; D015233:Models, Statistical; D051381:Rats