Glutaraldehyde inactivated pertussis vaccine: a less histamine sensitizing vaccine.

The effects of different inactivating agents on the biological activity of the histamine sensitization factor of Bordetella pertussis toxin were examined. The agents were used for inactivation in the preparation of whole cell pertussis suspension. The histamine sensitizing activity was reduced to 36.9-13.3% by treatment with glutaraldehyde, to about 50% by treatment with formaldehyde and by the acetone-II treatment, relative to the reduction by heat treatment. Treatment with thimerosal and the acetone-I treatment did not reduce the histamine sensitizing activity as the 50% histamine sensitizing doses of the heat inactivated pertussis preparation, the thimerosal inactivated pertussis preparation and the acetone-I treated pertussis preparation were very similar. Glutaraldehyde has thus been found to be a better inactivating agent for the preparation of a safe pertussis suspension as it considerably reduced the histamine sensitizing activity of pertussis toxin.