title: [Serological investigation on close contacts to patients with severe acute respiratory syndrome in an SARS outbreak].
abstract: OBJECTIVE
  To study the evidence of severe acute respiratory syndrome (SARS) infection among close contacts to SARS patients and the level of sera IgG antibody in SARS cases.
  
  
  METHODS
  Specific IgG antibody against SARS-CoV in serum samples from contacts to patients, five months before an SARS outbreak in Beijing. Neutralized test, ELISA and immunity adherence test were studied. Samples were collected after clinical onset of patients or close contacts to patients, for 22 - 24 weeks. 19 close contacts and 13 cases were included in the study.
  
  
  RESULTS
  In close contacts, all tests were negative on three methods. All SARS cases were positive except one by immunity adherence test. The neutralized antibody levels were from 1:16 to 1:203, with medium level of 1:43.
  
  
  CONCLUSIONS
  According to our survey, there was no latent infection among close contacts. IgG antibody in sera continued to be at higher levels among SARS cases 22 - 24 weeks after onset.
authors.affiliation: Chinese Field Epidemiology Training Program, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
authors.forename: Shu-yun
authors.initials: SY
authors.lastname: Xie
authors.forename: Guang
authors.initials: G
authors.lastname: Zeng
authors.forename: Jiang-ting
authors.initials: JT
authors.lastname: Chen
authors.forename: Yu-xuan
authors.initials: YX
authors.lastname: Liu
authors.forename: Shu-fen
authors.initials: SF
authors.lastname: Li
authors.forename: Wei-dong
authors.initials: WD
authors.lastname: Yin
mesh_terms: D000914:Antibodies, Viral / Q000097:blood*; D002681:China / Q000453:epidemiology; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D045473:Severe acute respiratory syndrome-related coronavirus / Q000276:immunology / Q000302:isolation & purification; D016036:Seroepidemiologic Studies; D045169:Severe Acute Respiratory Syndrome / Q000453:epidemiology* / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G