Immunology of Varicella Immunization in the elderly.
OBJECTIVE
To review the varicella-zoster virus (VZV) and herpes zoster disease and to summarize published reports on the use of the live-attenuated varicella zoster vaccine to enhance cell-mediated immunity in elderly individuals.


METHODS
A MEDLINE search (1966-August 1999) for English-language clinical studies and review articles pertaining to VZV and the live-attenuated varicella vaccine was conducted; references obtained from these publications were subsequently reviewed for additional relevant articles.


METHODS
Representative clinical trials were summarized and relevant information was selected to assist in the understanding of VZV, the subsequent immune response, and the live-attenuated varicella vaccine.


RESULTS
The physiologic, age-related decline in VZV cell-mediated immunity has been shown to be restored on administration of live-attenuated varicella vaccine. Various studies report serum anti-VZV antibody concentrations, and production of interferon-gamma were increased following vaccination. Concentrations subsequently returned to baseline one year after vaccination. Increase in responder cell frequency, a measure of cell-mediated immunity, has been reported to last up to four years after vaccination, at concentrations similar or superior to those observed following herpes zoster.


CONCLUSIONS
Enhancement of cell-mediated immune response in elderly individuals through vaccination with live-attenuated varicella vaccine is a possible measure to protect this population from herpes zoster and to attenuate its complications. A summary of immunogenicity studies to identify the immune response to live-attenuated varicella vaccine in the elderly is presented. The absolute clinical significance, as well as appropriate administration guidelines of this prophylactic intervention, will become evident following forthcoming large, masked, placebo-controlled trials.
Raeder
C K
CK
School of Pharmacy, University of Wisconsin-Madison, 53706, USA.
Hayney
M S
MS
D000368:Aged; D002644:Chickenpox / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D019433:Chickenpox Vaccine / Q000276:immunology*; D014645:Herpesvirus 3, Human / Q000276:immunology; D006801:Humans; D014611:Vaccination
D019433:Chickenpox Vaccine