Measles immunisation non-acceptance: validation of computer-held records and raising the vaccine uptake at early school age; the Maidstone experience.

The parents of all 977 resident children born in 1981 and 1982 recorded as not having received measles vaccine were contacted by letter. They were strongly advised to seek immunisation for their children and asked to complete and return a reply-paid questionnaire. Details of their children's immunisation status, reasons for non-immunisation and history of measles infection were sought, and whether they then intended to have their children immunised. The response rate was 53.3%. Of responders, 27% claimed to have written evidence that their children had already been immunised, the majority of them having been done outside the District. There was a high degree of mobility, mainly into the District, emphasising the need to record immunisation status when registering newly arrived children. The main reasons for non-immunisation were: a history of measles infection, personal or family history of fits or allergy, and mistrust of the vaccine. Many parents had been inappropriately advised by health professionals. 78 children from these cohorts are now known to have been vaccinated in the three months following the mailing and these together with the validation exercise have raised vaccination cover for 1981-born children from 74.7% to 78.9% and for 1982-born children from 77.0% to 81.4%.