title: Clinical and economic impact of various strategies for varicella immunity screening and vaccination of health care personnel.
abstract: BACKGROUND
  Exposure to patients with varicella or herpes zoster causes considerable disruption to a health care facility's operations and has a significant health and economic impact. However, practices related to screening for immunity and immunization of health care personnel (HCP) for varicella vary widely.
  
  
  METHODS
  A decision tree model was built to evaluate the cost-effectiveness of 8 different strategies of screening and vaccinating HCP for varicella. The outcomes are presented as probability of acquiring varicella, economic impact of varicella per employee per year, and cost to prevent additional cases of varicella. Monte Carlo simulations and 1-way sensitivity analyses were performed to address the uncertainties inherent to the model. Alternative epidemiologic and technologic scenarios were also analyzed.
  
  
  RESULTS
  Performing a clinical screening followed by serologic testing of HCP with negative history diminished the cost impact of varicella by >99% compared with not having a program. Vaccinating HCP with negative screen cost approximately $50,000 per case of varicella prevented at the current level of U.S. population immunity, but was projected to be cost-saving at 92% or lower immunity prevalence. Improving vaccine acceptance rates and using highly sensitive assays also optimize cost-effectiveness.
  
  
  CONCLUSIONS
  Strategies relying on screening and vaccinating HCP for varicella on employment were shown to be cost-effective for health care facilities and are consistent with current national guidelines for varicella prevention.
authors.affiliation: National Center for Occupational Health and Infection Control, Veterans Health Administration Office of Public Health, Gainesville, FL; Miami Veterans Affairs Healthcare System, Miami, FL; University of Miami Miller School of Medicine, Miami, FL. Electronic address: gio.baracco@va.gov.
authors.forename: G J
authors.initials: GJ
authors.lastname: Baracco
authors.affiliation: National Center for Occupational Health and Infection Control, Veterans Health Administration Office of Public Health, Gainesville, FL; University of South Florida, College of Public Health, Tampa, FL.
authors.forename: S
authors.initials: S
authors.lastname: Eisert
authors.affiliation: Veterans Affairs Caribbean Healthcare System, San Juan, Puerto Rico.
authors.forename: S
authors.initials: S
authors.lastname: Saavedra
authors.affiliation: Occupational Health, Veterans Health Administration Office of Public Health, Washington, DC.
authors.forename: P
authors.initials: P
authors.lastname: Hirsch
authors.affiliation: National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA.
authors.forename: M
authors.initials: M
authors.lastname: Marin
authors.affiliation: National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA.
authors.forename: I R
authors.initials: IR
authors.lastname: Ortega-Sanchez
mesh_terms: D000914:Antibodies, Viral / Q000097:blood*; D002644:Chickenpox / Q000276:immunology*; D019433:Chickenpox Vaccine / Q000008:administration & dosage / Q000191:economics*; D003362:Cost-Benefit Analysis; D003428:Cross Infection / Q000517:prevention & control; D006282:Health Personnel; D006801:Humans; D008403:Mass Screening / Q000191:economics* / Q000379:methods*; D015233:Models, Statistical; D009784:Occupational Diseases / Q000517:prevention & control; D014611:Vaccination / Q000191:economics* / Q000379:methods
chemical_list: D000914:Antibodies, Viral; D019433:Chickenpox Vaccine
keywords: Immunization; Model; Occupational exposure; Occupational health; Screening; Varicella