title: Varicella screening and vaccination for healthcare workers at KK Women's and Children's Hospital.
abstract: BACKGROUND
  Varicella is a highly contagious disease with significant morbidity and mortality, especially in adults. It can lead to nosocomial transmission with dire consequences, especially in a healthcare facility where children and pregnant women form the majority of patients. At KK Women's and Children's Hospital, we embarked on a programme in 2 phases, between 1997 and 1999, to screen healthcare workers (HCWs) for varicella immunity and to offer varicella vaccination to those who tested negative for antibody.
  
  
  METHODS
  HCWs were initially screened via a questionnaire; those with no previous history of chickenpox underwent a blood test for varicella zoster antibody. Varicella vaccine was offered to those who tested negative for antibody and they were monitored for adverse reactions.
  
  
  RESULTS
  Of the HCWs surveyed, 14.7% and 26.9% in phases 1 and 2, respectively, had no previous history of chickenpox. Of these, 55.3% in phase 1 and 26.1% in phase 2 tested negative for antibodies. Thus, the overall seronegativity of all HCWs surveyed was between 6.5% and 7.6%. Among those who tested negative for antibodies, 42.9% in phase 1 and 74% in phase 2 were vaccinated. Hence, the overall vaccination rate in HCWs was 3.2% and 4.8% in phases 1 and 2, respectively. Adverse reactions were observed in 2 (22.2%) HCWs in phase 1 and in 9 (9.3%) in phase 2, consisting mostly of maculopapular rashes or vesicles around the injection site.
  
  
  CONCLUSIONS
  Our study shows that 26% to 55% of HCWs with no history of chickenpox and who tested negative for antibody against varicella required vaccination. Hence, in healthcare facilities, varicella screening and vaccination should be offered to all HCWs.
authors.affiliation: Infectious Disease Service, Department of Paediatrics, KK Women's and Children's Hospital, Singapore. cychong@kkh.com.sg
authors.forename: C Y
authors.initials: CY
authors.lastname: Chong
authors.forename: S H
authors.initials: SH
authors.lastname: Lim
authors.forename: W Y M
authors.initials: WY
authors.lastname: Ng
authors.forename: N
authors.initials: N
authors.lastname: Tee
authors.forename: R V T P
authors.initials: RV
authors.lastname: Lin
mesh_terms: D000328:Adult; D000914:Antibodies, Viral / Q000097:blood; D019433:Chickenpox Vaccine; D006282:Health Personnel; D006306:Health Surveys; D006562:Herpes Zoster / Q000175:diagnosis* / Q000276:immunology / Q000517:prevention & control*; D014645:Herpesvirus 3, Human / Q000276:immunology; D006776:Hospitals, Pediatric; D006801:Humans; D009784:Occupational Diseases / Q000175:diagnosis* / Q000276:immunology / Q000517:prevention & control*; D015397:Program Evaluation; D012846:Singapore; D014611:Vaccination; D014932:Women's Health Services
chemical_list: D000914:Antibodies, Viral; D019433:Chickenpox Vaccine