Varicella Vaccine: What Have You Done for Me Lately?

* Abbreviation: VZV — : varicella zoster virus The live attenuated varicella vaccine remains the only vaccine in use against a virus that has a latent form and therefore causes 2 illnesses: varicella and zoster (also known as shingles).1 Zoster occurs after latent infection with varicella zoster virus (VZV) reactivates, after either chickenpox or vaccination. Viral latency lasts a lifetime. In countries where the vaccine is not used, varicella is mainly a disease of children, and zoster is a disease of adults. Because of declining cell-mediated immunity in older individuals, the incidence of zoster increases sharply after age 50. However, zoster may occur at any age in individuals who have previously been infected with VZV, and children vaccinated against chickenpox are at risk. In addition to waning cellular immunity with age, other factors that may precipitate zoster include immunosuppression, other viral infections, and stress.1 The varicella vaccine was developed in Japan in 1974, after Takahashi et al2 successfully attenuated VZV that was obtained from an otherwise healthy child with chickenpox. When the varicella vaccine was initially tested in the United States in the late 1970s, children with leukemia were frequently on their way to being cured of … Address correspondence to Anne A. Gershon, MD, Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons, 630 W 168th St, New York, NY 10032. E-mail: aag1{at}cumc.columbia.edu