Childhood immunisation today.

Better knowledge of the pathogenesis of infections and host responses, and progress in biotechnology, have paved the way for new vaccines. In spite of rapid progress with several vaccine candidates, overoptimism is, however, not warranted. There is usually several years' delay before the new vaccine from the laboratory is available in practice. Acellular pertussis vaccine and rotavirus vaccine are examples of new vaccines that are currently being introduced; varicella, inactivated polio, and hepatitis B vaccines have been suggested for use in a new and more efficient way. In order to keep up high motivation among families and thus high vaccination coverage, more emphasis must be put on information about vaccines, their properties and proper use. Economic analyses are becoming more important in the decision to use new vaccines. Therefore, cost-benefit, cost-effectiveness and cost-utility analyses need to be conducted so that a basis can exist for determining a rational policy.