Travel vaccines--a review of current thinking

More controversial aspects of the administration of vaccines are discussed with particular emphasis on the uncertainties surrounding measurement and significance of immunological markers in predicting efficacy. New areas of vaccine development are highlighted, particularly the importance of greater understanding of the gut immune mechanisms which promise oral delivery routes for a variety of immunogens. Emphasis is laid on the requirement for expert administration of intradermal injection if protection is to be reliable. Several new vaccines have been introduced recently and relevant issues relating to typhoid, cholera and hepatitis A vaccines are discussed. New possibilities for immunisation against travellers diarrhoea are appraised. The required frequency of booster doses is discussed for several vaccines where it is found that long term protection has often not been well researched. This is nowhere better demonstrated than with hepatitis B. Finally less commonly used vaccines are discussed and the importance of assessing true risk before deciding on use is emphasized.