title: The prevalence of Keshan disease in China.
abstract: BACKGROUND
  Sentinel surveillance of Keshan disease (KD) is limited by unable to give the prevalence rates and their estimates. This study was to find the national KD prevalence and the estimated patient numbers to provide evidence toward modifying the policy of KD prevention and control.
  
  
  METHODS
  Using a probability proportional to population size, randomized, multistage, and cluster sampling, we surveyed 101,127, measured grain selenium levels; and surveyed household income with pre-designed questionnaires.
  
  
  RESULTS
  The national prevalence rates of KD, chronic KD and latent KD were 2.21%, 0.50%, and 1.71% respectively. Chronic KD patients are mainly in the provinces where KD had been seriously epidemic. The KD prevalence rate was higher in females (2.20%) than in males (1.98%). These were also higher in older age groups. The cases younger than 30 years accounted for 13.6%, indicating the possibility that KD is still occurring. Nationally, the estimated numbers of KD and chronic KD patients are 1,675,500 (95% CI, 1,608,500-1,747,300) and 379,800 (95% CI, 346,700-412,800) respectively. Multiple logistic regression analysis indicated that family income was a significant dependent variable (OR: -0.258, 95% CI: -0.332 to -0.185, p<0.001). More than 2000 chronic KD patients found in the study were treated in 2009-2011. The limitation of this study was that sampling size was determined at national level.
  
  
  CONCLUSIONS
  KD is still a public health issue among the people of the historically severe endemic areas. Selenium supplementation, self-management program for chronic KD patients and translation epidemiology of KD surveillance should be strengthened.
authors.affiliation: Institute of Keshan Disease, Chinese Center for Endemic Disease Control, Harbin Medical University, China; The Third Affiliated Hospital of Harbin Medical University, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Li
authors.forename: Mingfa
authors.initials: M
authors.lastname: Liu
authors.forename: Jie
authors.initials: J
authors.lastname: Hou
authors.forename: Changxing
authors.initials: C
authors.lastname: Jiang
authors.forename: Shaochen
authors.initials: S
authors.lastname: Li
authors.forename: Tong
authors.initials: T
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D009202:Cardiomyopathies / Q000175:diagnosis* / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D003430:Cross-Sectional Studies; D004769:Enterovirus Infections / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011795:Surveys and Questionnaires; D055815:Young Adult