Abstract :
While live attenuated Oka Merck strain varicella vaccine has been safe and effective in reducing the disease burden worldwide, it had not been investigated in the Indian population. With the purpose of obtaining licensure in India, we evaluated the safety and immunogenicity of a single dose of varicella-zoster virus (VZV) vaccine in healthy children (1–12 years), history-negative for varicella. Immunogenicity was assessed at 6 weeks postvaccinationfor childrenseronegative before vaccination, by estimating VZV-specific antibody titer usingglycoprotein-based enzyme-linked immunosorbent assay (gpELISA) and geometric mean titer (GMT). For safety assessment, all injection-site and systemic adverse events (AEs) were recorded for all childrenuntil 6 weeks postvaccination.All 130 children enrolled (mean age, 4.8 years) received 1 dose of the vaccine. Of the immunogenicity cohort(n=108), 84.3% had VZVspecific antibody titers ?5 gpELISA units/mL (95% CI 76.0, 90.6) 6 weeks postvaccination,with overall antibody GMT of 9.9 gpELISA units/mL (95% CI 8.7, 11.2). Of the vaccinated cohort (N=130), 43.8% children experienced ?1 AE, most were mild in intensity; the most frequently reported AEs were pyrexia (19.2%), cough (17.7%), nasopharyngitis (12.3%), and injection-site pain (6.2%). Rasheswere reported in 3.8%and injection-site reactions in 10% children. No serious AEs were reported and no participant discontinued the study because of an AE. This study demonstrateshigh immunogenicity and good tolerability of VZV vaccine in healthy Indian children. This has implications for incorporation of VZV vaccination into a universal immunization program in India to curb varicella. Clinicaltrials.gov NCT00496
Keyword :
Children, Immunogenicity, Safety, Vaccine, Varicella