title: Serosurveillance of varicella and hepatitis B infection after reported cases in medical students and the relationship between past varicella disease history and immunity status.
abstract: OBJECTIVE
  To identify seroprevalence of varicella and the relationship with their histories of experiences of varicella diseases and to provide appropriate immunization against varicella, mumps, measles, rubella and hepatitis B to medical students.
  
  
  METHODS
  All of the medical students were eligible for participation after informed consents. Immunization history against varicella, mumps, measles, rubella (MMR) and hepatitis B were obtained from a questionnaire. A blood sample was obtained from each student for IgG antibody against VZV by ELISA. Medical students with an uncertain history or no documentation of hepatitis B vaccination were tested for HBsAg and anti-HBcIgG by ELISA.
  
  
  RESULTS
  There were 383 medical students enrolled. The mean age at enrollment was 21.6 years (median 21.4 years; range 18-25.8 years). Of 383 medical students, 372 (97.2%) had documents of receiving MMR immunizations. The blood samples were obtained from 374 of 383 (97.6%) medical students to identify the immunity against varicella zoster virus (VZV) and the seroprevalence rate was 92%. Using VZVIgG antibody detection as a standard test, history of experience of varicella disease provided positive predictive value of 99.3% (148/149). Of 383 medical students, 277 (72.3%) were tested for hepatitis B markers and 243 (87.7%) students showed negative results. The prevalence of HBsAg carriers was 0.01% (4/383).
  
  
  CONCLUSIONS
  Suboptimal immunities against vaccine preventable diseases could be demonstrated in the medical students including varicella and hepatitis B. New recommendations of immunizations against varicella, MMR and hepatitis B viruses for a particular group of the population were provided.
authors.affiliation: Department of Pediatrics, Phramongkutklao Hospital, Bangkok, Thailand.
authors.forename: Detchvijitr
authors.initials: D
authors.lastname: Suwanpakdee
authors.forename: Chalida
authors.initials: C
authors.lastname: Laohapand
authors.forename: Visal
authors.initials: V
authors.lastname: Moolasart
authors.forename: Prasong
authors.initials: P
authors.lastname: Lomtong
authors.forename: Nat
authors.initials: N
authors.lastname: Krairojananan
authors.forename: Phutsapong
authors.initials: P
authors.lastname: Srisawat
authors.forename: Veerachai
authors.initials: V
authors.lastname: Watanaveeradej
mesh_terms: D016009:Chi-Square Distribution; D002644:Chickenpox / Q000453:epidemiology / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology / Q000276:immunology* / Q000517:prevention & control; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008457:Measles / Q000517:prevention & control; D022542:Measles-Mumps-Rubella Vaccine / Q000008:administration & dosage; D009107:Mumps / Q000517:prevention & control; D011237:Predictive Value of Tests; D012409:Rubella / Q000517:prevention & control; D016036:Seroepidemiologic Studies; D013337:Students, Medical; D011795:Surveys and Questionnaires; D013785:Thailand / Q000453:epidemiology; D055815:Young Adult
chemical_list: D007074:Immunoglobulin G; D022542:Measles-Mumps-Rubella Vaccine