The Effect of Decreasing Amounts of Live Virus, while Antigen Content Remains Constant, on Immunogenicity of Oka/Merck Varicella Vaccine

• Published in: The Journal of infectious diseases Vol. 168; no. 6; pp. 1356 - 1360
• Main Authors: Watson, Barbara, Piercy, Sharon, Soppas, Despina, Browngoehl, Kevin, Warner, Mark, Isganitis, Kathy, White, C. J., Kuter, Barbara, Chua, Janet, Starr, Stuart
• Format: Journal Article
• Language: English
• Published: Chicago, IL University of Chicago Press 01.12.1993
• Subjects: Antibodies; Antibodies, Viral - biosynthesis; Antigens; Antigens, Viral - immunology; Biological and medical sciences; Chickenpox; Chickenpox - prevention & control; Chickenpox Vaccine; Child; Child, Preschool; Dosage; Dose-Response Relationship, Immunologic; Enzyme linked immunosorbent assay; Female; Freezing; Herpesvirus 3, Human - immunology; Human viral diseases; Humans; Immune response; Immunization; Infectious diseases; Lymphocyte Activation; Major Articles; Male; Medical sciences; Vaccination; Vaccines, Attenuated - administration & dosage; Vaccines, Attenuated - immunology; Vaccines, Attenuated - therapeutic use; varicella-zoster virus; Viral antigens; Viral diseases; Viral diseases with cutaneous or mucosal lesions and viral diseases of the eye; Viral Vaccines - administration & dosage; Viral Vaccines - immunology; Viral Vaccines - therapeutic use; Human; Varicella zoster virus; Minimum; Temperature; Antibody; Herpesviridae; Vaccination; Alphaherpesvirinae; Conservation; Vaccine; Infection; Virus; Antigen; Immunogenicity; Immunological investigation; Viral disease; Varicella; Child; Humoral immunity
• ISSN: 0022-1899
• DOI: 10.1093/infdis/168.6.1356

The purpose of the study was to establish the minimum immunizing dose of stored Oka/Merck varicella vaccine and mimic effects of prolonged storage of vaccine at freezer temperatures. Ninety children were randomized to one of three groups: group A (1770 pfu/dose), group B (400-500 pfu/dose), or group C (80-160 pfu/dose). Seroconversion rates for groups A-C were 970Zo, 960Zo, and 9207o, respectively. Group A and B vaccinees had higher antibody titers at 1 year than did group C subjects (P = .01). The difference between groups B and C approached significance (P = .058). At 1 year after immunization, 730Zo, 830Zo, and 8007o in groups A-C, respectively, demonstrated cell-mediated responses. Since freshly reconstituted vaccine contains 1770 pfu/ dose, vaccine failure from loss of potency is unlikely if vaccine is stored properly and administered promptly after reconstitution.