title: Varicella vaccination in HIV-1-infected children after immune reconstitution.
abstract: BACKGROUND
  HIV-1-infected children have an increased risk of severe chickenpox. However, vaccination is not recommended in severely immunocompromised children.
  
  
  OBJECTIVE
  Can the live-attenuated varicella zoster virus (VZV) Oka strain be safely and effectively given to HIV-1-infected children despite previously low CD4 T-cell counts?
  
  
  METHODS
  VZV vaccine was administered twice to 15 VZV-seronegative HIV-1-infected children when total lymphocyte counts were greater than 700 lymphocytes/microl, and six HIV-negative VZV-seronegative siblings. Weekly clinical follow-up and sampling were performed.
  
  
  RESULTS
  None of the children developed any clinical symptom or serious adverse reaction after immunization. Only nine (60%) of the HIV-1-infected children had VZV-specific antibodies after two immunizations, whereas 100% of the siblings seroconverted. Age at baseline was negatively correlated with the VZV IgG titre at 6 weeks after the second vaccination in HIV-1-infected children. VZV-specific antibody titres after two immunizations were at a similar level to those found after wild-type infection in non-vaccinated HIV-1-infected patients, but significantly lower than in HIV-negative siblings. Importantly, VZV-specific T-cell responses increased after vaccination and were comparable in both groups over time. Documented wild-type VZV contact in three vaccinated patients did not result in breakthrough infections.
  
  
  CONCLUSIONS
  VZV vaccination of previously immunocompromised HIV-1-infected children was safe. Vaccination induced specific immune responses in some of the vaccinated HIV-1-infected children, suggesting that previously immunocompromised individuals are protected against severe forms of varicella.
authors.affiliation: Emma Children's Hospital, The Netherlands.
authors.forename: Vincent
authors.initials: V
authors.lastname: Bekker
authors.forename: Geertje H A
authors.initials: GH
authors.lastname: Westerlaken
authors.forename: Henriëtte
authors.initials: H
authors.lastname: Scherpbier
authors.forename: Sophie
authors.initials: S
authors.lastname: Alders
authors.forename: Hans
authors.initials: H
authors.lastname: Zaaijer
authors.forename: Debbie
authors.initials: D
authors.lastname: van Baarle
authors.forename: Taco
authors.initials: T
authors.lastname: Kuijpers
mesh_terms: D000914:Antibodies, Viral / Q000032:analysis / Q000096:biosynthesis; D000918:Antibody Specificity / Q000276:immunology; D002644:Chickenpox / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D014645:Herpesvirus 3, Human / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D018655:Lymphocyte Count; D008297:Male; D012307:Risk Factors; D035781:Siblings; D013601:T-Lymphocytes / Q000276:immunology; D014613:Vaccines, Attenuated / Q000627:therapeutic use; D014765:Viral Vaccines / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G; D014613:Vaccines, Attenuated; D014765:Viral Vaccines