Travel vaccines and elderly persons: Review of vaccines available in the United States

Aging is associated with alterations in immune responses and may lead to cl inically significant changes in the safety, immunogenicity, and protective efficacy of certain vaccines. This review summarizes published data regardi ng the effects of age on responses after immunization with vaccines general ly administered before travel. The specific vaccines discussed in detail in clude hepatitis A, typhoid, yellow fever, Japanese encephalitis, and rabies vaccines. There is some evidence of diminished serological responses to he patitis A and rabies vaccines in older individuals. In addition, increased toxic effects following yellow fever vaccination in elderly recipients have recently been reported. However, many travel-related vaccines have never b een studied specifically in elderly populations. Consideration of potential age-related differences in responses to travel vaccines is becoming increa singly important as elderly persons more frequently venture to exotic desti nations.