Immunisation practice and policy.

Immunisation has proved to be a generally safe and effective means of disease control, particularly where environmental approaches are impractical. Recent developments in vaccine production, aimed at selecting or synthesising in pure form the antigens needed to evoke a protective response, give hope of more effective and less toxic vaccines in future. Adequate trials of improved vaccines may, however, be difficult to carry out under modern conditions. Policies for the use of vaccines are sometimes controversial, particularly when there is concern about reactions, as with pertussis vaccine. Acceptance rates for measles and rubella vaccines in the UK have hitherto been disappointingly low and need to be increased if the aims of elimination of measles and congenital rubella are to be achieved. Cost-benefit analyses generally support the use of immunisation in disease control.