title: A systematic review of the investigation and management of close contacts of tuberculosis in China.
abstract: BACKGROUND
  Contact investigation is a logical approach to intensified case finding in China. However, currently there are no written national guidelines. The aim of this study is to review the published literature that describes the procedures followed by local level and report the yield for active tuberculosis (TB) cases.
  
  
  METHODS
  Studies conducted in China and published between 1997 and 2007 on contact investigation were searched.
  
  
  RESULTS
  Twelve studies were included in the review. There was no standard definition of contact and no study provided details on how to prioritize contacts. Investigation methods vary between each study. The number of contacts investigated per index case ranged from 22.7 to 658 in congregate settings and from 1.5 to 5.8 in household. The yields for active TB ranged from 0 to 11.765% in congregate settings and from 0 to 6.897% in household. The weighted yields for smear-positive index and smear-negative index were 1 and 0.2% respectively in household and 0.5% for pulmonary case index in congregate settings.
  
  
  CONCLUSIONS
  There is considerable heterogeneity amongst the methods used and the cases yielded in these studies, and in general the quality of contact investigation is low; therefore, there is a need for China to develop national guidelines on contact investigation.
authors.affiliation: National Center for TB Control and Prevention, China CDC, Beijing 100050, China.
authors.forename: Eryong
authors.initials: E
authors.lastname: Liu
authors.forename: Shiming
authors.initials: S
authors.lastname: Cheng
authors.forename: Xuejing
authors.initials: X
authors.lastname: Wang
authors.forename: Dongmei
authors.initials: D
authors.lastname: Hu
authors.forename: Tianhao
authors.initials: T
authors.lastname: Zhang
authors.forename: Cordia
authors.initials: C
authors.lastname: Chu
mesh_terms: D002681:China / Q000453:epidemiology; D016358:Contact Tracing / Q000379:methods* / Q000639:trends; D006801:Humans; D008403:Mass Screening; D009161:Mycobacterium / Q000302:isolation & purification*; D014376:Tuberculosis / Q000453:epidemiology* / Q000635:transmission