Reactions 397 - 18 Apr 1992

Does pertussis immunisationcause brain injury?

In a recent perspective, Dr P Camfield, a neurologistfrom IWK Children’s Hospital and Dalhousie University,Nova Scotia, Canada, examined the issues andconcluded that pertussis immunisation does not causebrain injury.

The pertussis component is the likely causative agentfor most complications of diphtheria, tetanus andpertussis (DTP) vaccine, including local inflammation,fever, irritability, drowsiness and a rare hypotonic-hyporesponsive state. None of these reactions areknown to lead to brain injury. However, several hundredcase reports have suggested an association betweenvaccine administration and development of infantileseizures, with subsequent permanent brain damage.Opinions based on these uncontrolled observationshave led to extensive litigation, a decrease inimmunisation rates and several pertussis epidemics.

Infantile spasms and fever-induced seizures are wellknown occurrences in infants, and these have beendemonstrated to result in both motor and intellectualimpairment. Since these occur during the same life stageas DTP immunisation, investigations to establish a causeand effect relationship are necessary to validate the casereports. Very few studies have been published.

A Danish study took advantage of a timing change inthe recommended immunisation schedule to look for acorresponding change in the timing of epileptiformactivity in vaccine recipients. No relationship could beestablished.

A British case-control study attempted to establish therelative risk of acute neurological events in infantsreceiving the vaccine. A crude relative risk wascalculated to be 2.4 and the attributable risk was 1:310000, although the 95% confidence interval was verywide. Further examination of this work led the authorsto conclude that infantile spasms are not connected toDTP immunisation In addition, 3 prospective cohortstudies, with a combined pool of 618 254 patients,encountered no cases of DTP-related encephalopathy

Thus, ’ timed observations, prospective cohorts, andcase-controlled studies have failed to demonstrate anyrelationship between DTP immunization and braininjury’Camfield P. Brain damage from Pertussis immunization. A Canadian neurologist’sperspective. American Journal of Diseases of Children 146: 327-331, Mar1992 800126445

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Reactions 18 Apr 1992 No. 3970114-9954/10/0397-0001/$14.95 Adis © 2010 Springer International Publishing AG. All rights reserved