Varicella vaccination in HIV-1-infected children after immune reconstitution.
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.
Bekker
Vincent
V
Emma Children's Hospital, The Netherlands.
Westerlaken
Geertje H A
GH
Scherpbier
Henriëtte
H
Alders
Sophie
S
Zaaijer
Hans
H
van Baarle
Debbie
D
Kuijpers
Taco
T
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*
D000914:Antibodies, Viral; D007074:Immunoglobulin G; D014613:Vaccines, Attenuated; D014765:Viral Vaccines