Whole cell pertussis
The WHO Requirements for whole cell Pertussis Vaccine were first formulated in 1963 while requirements for Diphtheria and Tetanus vaccines were prepared in 1964. Since Diptherica, Tetanus and whole cell Pertussis (DTwP) vaccines have been commonly used in a combined form, the requirements revised in 1978 encompassed all three components as a separate section followed by a final section that applied to a combination. The last revision of requirements for Diptheria, Tetanus, Pertussis and combined vaccines was in 1989 and published in 1990.
Since that time a number of developments have taken place in the production, standardization and quality control of DTP vaccines, as well as in the understanding of Bordetella pertussis, and it was considered that the existing requirements should be reviewed and where appropriate revised and updated. An amendment to the D and T section concerning single dilution and in vitro potency assays was adopted by the Expert Committee on Biological Standardization in 2004. The present revision of the requirements for whole cell pertussis vaccine should therefore be considered as part of the revision of whole requirements for DTP. In 1998 the name WHO Requirements was changed to WHO Recommendations to better reflect the nature of these documents. These recommendations for whole cell pertussis vaccine supersede those published in 1990 and should be read in conjunction with the recommendations for D and T vaccines when whole cell pertussis vaccine is part of DTwP combined vaccine. Once both the Diptheria and Tetanus sections have also been fully revised, it is the intention to incorporate all the three sections into one document.
Since 1989 a variety of combination vaccines based on DTP and involving a number of additional antigens have been developed and licensed. Many countries have already included tetravalent and pentavalent vaccines containing Hepatitis B, Haemophilus influenzae type b conjugate (Hib) and Inactivated Polio vaccines (IPV), in addition to DTwP, in their immunization programmes. A need for further guidance on the evaluation of combination vaccines based on DTwP has been recognized and will be developed into a different document.
In addition, a number of acellular pertussis vaccines have been licensed and used in combination with other vaccines for more than twenty years. Separate Guidelines for the production and control of the acellular pertussis component of monovalent or combined vaccines, were developed in 1996 and their revision is also being undertaken separately.