Major review finds acellular pertussis vaccines safe, severe side effects rare
A comprehensive analysis of decades of safety data confirms that acellular pertussis vaccines cause mostly mild, temporary reactions, with serious complications like seizures occurring at no higher rates than in unvaccinated populations. The findings are significant for public health officials and manufacturers defending vaccine confidence as safety concerns resurface in some markets.
Originaltitel: Update on Selected Adverse Events of Concern Following Immunization With Acellular Pertussis Vaccines, a Narrative Review.
# Vaccinsäkerhet och marknadförtroende — dansk studie stärker evidensen för cellulösa pertussivacciner Vaccintillverkare och hälsovårdsmyndigheter får nu uppdaterad vetenskaplig grund för att kommunicera pertussivaccinsäkerhet. En omfattande litteraturöversikt från Linköpings universitet och Folkhälsomyndigheten, publicerad i Acta Paediatrica, sammanfattar decenniernas forskning på biverkningar efter cellulösa pertussivacciner (aP-vacciner). Studien bekräftar att alvarliga händelser som kramper eller encefalopati inte ökar över basgränsen i stora populationsstudier. Vanligare är milda reaktioner — lokal smärta, rodnad och tillfällig feber. Måttliga biverkningar som förlängd gråt eller omfattande svullnad förekommer sällan och är självbegränsande. För aktörer inom vaccinfarmaci och offentlig hälsa är detta kritiskt: evidensen möjliggör faktabaserad kommunikation som bevara vaccinförtroende samtidigt som man undviker överdriven riskbeskrivning. Kontinuerlig läkemedelsövervakning förblir väsentlig för långsiktig programtrovärdighet.
AIM: To provide an update paper on evidence of adverse events of concern following immunization (AEFI) with pertussis vaccines, focusing primarily on acellular (aP) vaccines. METHODS: Evidence was synthesised from epidemiological studies, systematic reviews over recent decades, expert interpretations in reviews from relevant research teams and well-conducted observational reports across different time periods. A more comprehensive review of the literature was conducted for certain specific AEFIs, including sterile abscesses, macrophagic myofasciitis, reactions to aluminium adjuvants, Guillain-Barré syndrome, acute disseminated encephalomyelitis (ADEM) and anaphylaxis. RESULTS: Acellular (aP) vaccines are generally associated with mild reactions such as local pain, redness, and transient fever. Moderate reactions, including prolonged crying, hypotonic-hyporesponsive episodes, extensive limb swelling, and aluminium-induced granuloma, occur infrequently and are self-limiting. Severe outcomes such as seizures or encephalopathy have been extensively investigated, with large studies showing no consistent increase above background incidence. CONCLUSION: Licensed acellular pertussis vaccine combinations demonstrate acceptable safety profiles, with serious adverse events being rare. Continuous pharmacovigilance and balanced, evidence-based communication remain essential to sustain trust in pertussis immunisation programmes.