Serious neurological
conditions following pertussis immunization: an analysis of endotoxin
levels, the vaccine adverse events reporting system (VAERS) database and
literature review.
Geier DA, Geier
MR.
MedCon, Inc., Silver Spring, MD, USA.
The purpose
of this study was to determine the potential risks for the development
and outcome of serious neurological illnesses following whole-cell DTP
vaccination and also to determine if the switch to using acellular DTaP
vaccine in the US has had any effect on the incidence rate of serious
neurological illnesses following vaccination. This study used the
Limulus amebocyte lysate (LAL) endotoxin assay to determine the levels
of endotoxin in various commercially available whole-cell and acellular
DTaP vaccines, analysed the Vaccine Adverse Events Reporting System
(VAERS) database to determine the clinical effects of the use of
whole-cell DTP and acellular DTaP vaccines in the US and reviewed
recently published pertinent studies that analysed the incidence rates
of serious neurological illness following whole-cell DTP and acellular
DTaP vaccines. The results indicated that whole-cell DTP vaccine
contained high levels of endotoxin and was statistically significantly
more reactogenic than acellular DTaP vaccine. The presence of bias in
the VAERS database was not borne-out. The recommendation by the American
Academy of Paediatrics to use acellular DTaP vaccine for the entire
childhood vaccination schedule beginning in 1996 and the absence of the
availability of whole-cell DTP in the US beginning in 2001 seems well
justified based upon the results of this study.