title: Antibody response to a delayed booster dose of anthrax vaccine and botulinum toxoid.
abstract: We evaluated the prevalence and concentration of serum antibodies 18-24 months after primary inoculation with anthrax and botulinum vaccines, and assessed the reactogenicity and immunogenicity of a significantly delayed booster dose of these vaccines. Five hundred and eight male active-duty military personnel received one, two or three inoculations with anthrax vaccine and/or botulinum toxoid in 1990/1991 in preparation for Operations Desert Shield/Desert Storm. Subjects were vaccinated with the licensed anthrax vaccine, adsorbed (AVA) and pentavalent (ABCDE) botulinum toxoid (PBT) BB-IND 3723. Anthrax protective antigen (PA) IgG antibody was measured in serum using an immunocapture enzyme-linked immunosorbent assay (ELISA). A mouse neutralization test was used to determine the titer of Clostridium botulinum type A antitoxin in serum samples. The prevalence of anti-PA IgG was 30% in individuals 18-24 months after priming with one, two or three doses of AVA. After boosting, 99% of volunteers had detectable anti-PA IgG; only two individuals failed to respond. The prevalence of antibodies against botulinum toxin type A was 28% 18-24 months after initial priming. Following boosting, 99% of volunteers had serum titers >0.02IU/ml, and 97% responded with titers > or =0.25IU/ml. Systemic reactions to booster vaccinations could not be specifically ascribed to one or the other vaccine, but were generally mild and of brief duration. Forty-five percent of volunteers reported one or more systemic reactions over the course of 7 days. Injection site reactions of any kind occurred in 25% of AVA recipients and in 16% of PBT recipients; persistence of local reactions beyond 7 days was infrequent. While the kinetics and durability of immune responses must be studied, these findings suggest that booster doses of anthrax vaccine and botulinum toxoid sufficient to stimulate a robust anamnestic response may be given at times distant from receipt of the primary inoculations.
authors.affiliation: United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD, USA. philip.pitmann@det.amedd.army.mil
authors.forename: Phillip R
authors.initials: PR
authors.lastname: Pittman
authors.forename: Dallas
authors.initials: D
authors.lastname: Hack
authors.forename: Joseph
authors.initials: J
authors.lastname: Mangiafico
authors.forename: Paul
authors.initials: P
authors.lastname: Gibbs
authors.forename: Kelly T
authors.initials: KT
authors.lastname: McKee
authors.forename: Arthur M
authors.initials: AM
authors.lastname: Friedlander
authors.forename: Maria H
authors.initials: MH
authors.lastname: Sjogren
mesh_terms: D000328:Adult; D022122:Anthrax Vaccines / Q000009:adverse effects / Q000276:immunology*; D000907:Antibodies, Bacterial / Q000097:blood*; D001905:Botulinum Toxins / Q000276:immunology*; D005260:Female; D006801:Humans; D007117:Immunization, Secondary; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors; D014121:Toxoids / Q000276:immunology*
chemical_list: D022122:Anthrax Vaccines; D000907:Antibodies, Bacterial; D014121:Toxoids; D001905:Botulinum Toxins