Immunity to diphtheria, six to 15 years after a basic three-dose immunization schedule.
The results of a study of the immunity to diphtheria of 283 girls (9-18 years of age) vaccinated at the age of two years with three doses of vaccine, are reported. The rabbit skin test was used to determine the titre of serum diphtheria antitoxin. 55.8% of the subjects were found to be protected (titre greater than or equal to 0.1 IU/ml), 38.9% were only relatively immune (titre greater than or equal to 0.01- less than 0.01 IU/ml), and 5.3% were unprotected (titre less than 0.01 IU/ml). The antitoxin titres showed a tendency to decrease with time. Even so, 6-15 years after vaccination, the percentages of protected and partially protected subjects were still high (95%).
Cellesi
C
C
Institute of Infectious Diseases, University of Siena, Italy.
Michelangeli
C
C
Rossolini
G M
GM
Giovannoni
F
F
Rossolini
A
A
D000293:Adolescent; D002648:Child; D004165:Diphtheria / Q000276:immunology / Q000517:prevention & control*; D004166:Diphtheria Antitoxin / Q000032:analysis; D004168:Diphtheria Toxoid / Q000008:administration & dosage*; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007558:Italy; D013997:Time Factors
D004166:Diphtheria Antitoxin; D004168:Diphtheria Toxoid