This article is from the Childhood Vaccinations FAQ, by Lynn Gazis-Sax firstname.lastname@example.org with numerous contributions by others.
Hypersensitivity to any component of the vaccine, including diptheria
toxoid and thimerosal in the multi-dose presentation.
Vaccine components capable of causing adverse reactions: phenol,
bacterial polysaccharides, thimerosal (Travel Medicine Advisor).
(Note: There is currently, as of 1999, a move toward replacing
thimerosal in vaccines, so the reference to thimerosal here may
shortly be out of date.)