Dose-dependent neutralizing-antibody responses to vaccinia.

Publication Type
Journal Article
Year of Publication
Belshe, Robert B; Newman, Frances K; Frey, Sharon E; Couch, Robert B; Treanor, John J; Tacket, Carol O; Yan, Lihan
J Infect Dis
Date Published
2004 Feb 01
Adolescent; Adult; Antibodies, Viral; Blister; Dose-Response Relationship, Immunologic; Female; Fever; Humans; Male; Neutralization Tests; Single-Blind Method; Smallpox Vaccine; United States; Vaccination; Vaccinia; Viral Plaque Assay

To evaluate the humoral immune responses to smallpox-vaccine stocks currently available in the United States (Dryvax; Wyeth) and to generate data for comparison of responses to newly produced lots of smallpox vaccine, we evaluated dose-response effects, using undiluted and diluted smallpox vaccine. At 28 and 56 days after vaccination, serum samples were obtained from vaccinated subjects (N=674) who had participated in a randomized, single-blinded trial of an undiluted or a 1 : 5 or 1 : 10 dilution of smallpox vaccine and who subsequently were tested for plaque-reduction neutralizing-antibody titer. All subjects who developed a vesicle after vaccination also developed neutralizing antibodies by day 28. Subjects given either a 1 : 5 or 1 : 10 dilution of vaccinia had significantly higher neutralizing-antibody titers than did subjects given undiluted vaccine. Larger lesion size and fever after vaccination were associated with significantly higher neutralizing-antibody titers after vaccination.