Vaccination Scheduling for Last-Minute Travellers

In general, as noted above under "Simultaneous Administration," most vaccine products can be given during one visit for those anticipating imminent travel. Unless the vaccines given are boosters of those typically given during childhood, every vaccine has a time period necessary for the host to develop sufficient antibodies, and this period of time may vary depending on the vaccine. This information is found in the Food and Drug Administration (FDA) drug information insert that accompanies each product.

Some vaccines require more than one dose for best protection. The use of multiple reduced doses or doses given at less than minimum intervals can lessen the antibody response. Because some travellers visit their health-care providers without ample time for administration of the several vaccine doses recommended for optimal protection against certain diseases, studies have been performed and others are ongoing to determine whether accelerated scheduling is adequate. This concern is primarily the case for hepatitis B vaccine or the combined hepatitis A and B vaccine (See Chapter 4). With imminent travel, a clinician may opt to accelerate these vaccine schedules, with the understanding that such administration has not been FDA approved and thus not endorsed by CDC. However, many travel medicine experts are using shortened schedules, feeling that they may provide better protection than the administration of just one dose of vaccine before travel. It is unclear what level of protection any given traveller will have if a full series of vaccination is not completed when more than one dose is recommended.