§ Mr. Barry FieldTo ask the Secretary of State for Health what progress has been made in connection with the clinical trials of the acellular pertussis vaccine which commenced in October 1987.
§ Mr. SackvillePhase II (immunogenicity and reactogenicity) studies have been undertaken using acellular pertussis vaccine, administered according to the previous434W (prior to May 1990) immunisation schedule. These results were published in the Lancet in January 1991. Studies are presently being undertaken to compare the vaccine with conventional whole cell vaccine given in a two, three and four-month schedule as used in the United Kingdom. Additional studies are also being carried out to investigate the duration of antibodies following acellular pertussis vaccine. Phase III (vacine efficacy) studies are being undertaken in Sweden; results will not be available until 1995–96.
§ Mr. Barry FieldTo ask the Secretary of State for Health how many reported reactions under the yellow card scheme have been received in which the pertussis vaccine was the vaccine alleged to be responsible for the reaction, in 1991 and 1992.
§ Mr. SackvillePertussis vaccine may be given as a single vaccine but is more usually given as a combined diphtheria, tetanus and pertussis (DTP) vaccine. The number of reports for each type of vaccine is as follows:
Vaccine 1991 1992 Pertussis 8 8 DTP 184 206 A report of a suspected adverse reaction does not necessarily mean that the reaction was caused by the vaccine.