VACCINATION AS PRIMARY CONTACT WITH INFLUENZA A AND B VIRUSES

[摘要] A single dose of 0.5 ml. of commercially available influenzal virus vaccine injected into children from seven weeks to three years of age produced antibodies in about 70%. Resulting antibody levels in the children, most of whom were born after the last widespread epidemics of influenza A and B, were distinctly lower than those observed in older individuals who, in all likelihood, had experienced previous contacts with influenzal antigens. Two injections at a week's interval failed to result in a better antibody response in these children in agreement with the experience gained in adults. Increase in the dose of vaccine appears unwarranted now, since the incidence of febrile reactions—all of short duration—exceeded 40%.This inferior antibody response may be the result of several factors: (a) the smaller dose of vaccine which can be safely administered to such children; (b) the possible inferior immune response of the younger individual; and (c) the absence of a basic immunity to the antigens present in most older individuals as a result of previous contacts with influenzal viruses.Although it is impossible to decide among these factors, the booster effect of restimulation with small doses of antigen is a well known phenomenon in protective measures against other infectious agents. It is felt that such a mechanism may well be the explanation for the discrepancies between young children and older individuals in their response to vaccination against influenza.

[学科分类] 儿科学