Efficacy of whooping-cough vaccines used in the United Kingdom before 1968. A preliminary report to the Director of the Public Health Laboratory service by the Public Health Laboratory Service Whooping-Cough Committee and Working Party.

In a large survey of the efficacy of pertussis vaccines made in 33 areas in the United Kingdom during the period 1 November 1966 to 31 October 1967 a total of 3,564 households were investigated. Nine hundred and seventy-seven strains of Bordetella pertussis and 6 strains of Bord. parapertussis were isolated from persons in 792 households.After contact in the home 56% of fully vaccinated children under 5 years of age developed a paroxysmal cough, and in more than two-thirds of these patients the diagnosis was confirmed bacteriologically. This suggests that pertussis vaccination was not very effective. A comparison with the attack rate in unvaccinated children also indicates a poor protection from vaccination.NONE OF THE FOLLOWING FACTORS APPEARED TO BE RESPONSIBLE FOR THE POOR PROTECTION AFFORDED BY VACCINATION: vaccination in early infancy, a long interval since vaccination, and the absence of booster doses.Almost all the children in the survey had been given vaccines from a single manufacturer, and therefore a comparison of the efficacy of vaccines prepared by different manufacturers was inconclusive. All the vaccinated children in the survey had been vaccinated before or during 1967. The efficacy of current preparations will require to be assessed by continuing surveillance.