Abstract
Purpose
There is no doubt that paediatric immunization prevents serious diseases, but the administration of these vaccines to healthy children also involves risks of adverse drug reactions (ADRs), some of which are potentially serious. The current body of evidence on ADRs from immunization therapy at the population level is partly contradictory across countries, time periods and childhood immunization programmes. The objective of our study was to characterize reported adverse events (AEFIs) following immunization in Danish children.
Methods
Adverse events (AEFIs) in 0- to 17-year-old children and adolescents reported to the Danish Medicines Agency (DKMA) between 1998 and 2007 were analysed. The unit of analysis was one AEFI. Data were categorized with respect to time, age, and gender of the children, suspected vaccines, category and seriousness of the AEFIs, and reporting rate.
Results
During the study period, the DKMA received 1,365 reports covering 2,600 AEFIs, corresponding to 60% of all adverse events reported for children. One third of the AEFIs were classified as serious, and two deaths were reported. The annual number of serious AEFIs remained constant during the study period. Approximately 80% of AEFIs were reported in children aged 0–2 years. Of all reported AEs, 45% were in the category “general disorders and administration site conditions”, followed by the categories “skin and subcutaneous tissue disorders” (20% of total AEFIs) and “nervous system disorders” (16% of total AEFIs). The largest share of serious events was from the category “nervous system disorders” (33% of serious AEFIs). The most frequently reported serious AEs were febrile convulsions, pyrexia, and injection-site reactions.
Conclusions
In Denmark, a large number of AEFIs following paediatric immunization have been reported, but the majority of cases were non-serious.
Similar content being viewed by others
References
Letourneau M, Wells G, Walop W, Duclos P (2008) Improving global monitoring of vaccines safety. A survey of national centres participating in the WHO programme for international drug monitoring. Drug Saf 31:389–398
Wendy E, Parmet JD (2010) Pandemic vaccines—the legal landscape. N Engl J Med 362:1949–1952
O’Brien KK (2009) Pharmacists’ role in preventing vaccine-preventable diseases. US Pharm 34:39–45
Mrożek-Budzyn D, Kiełtyka A, Majewska R (2010) Lack of association between measles–mumps–rubella vaccination and autism in children: a case-control study. Pediatr Infect Dis J 29:397–400
Madsen KM, Hviid A, Vestergaard M, Schendel D, Wohlfahrt J, Thorsen P, Olsen J, Melbye M (2002) A population-based study of measles, mumps, and rubella vaccination and autism. N Engl J Med 347:1477–1482
Hviid A, Stellfeld M, Wohlfahrt J, Melbye M (2004) Childhood vaccination and type 1 diabetes. N Engl J Med 350:1398–1404
Hviid A, Melbye M (2008) Measles–mumps–rubella vaccination and asthma-like disease in early childhood. Am J Epidemiol 168:1277–1283
Harris E (2010) After Wakefield: the real questions that needs addressing. Br Med J 340:c2829
Jacobson RM (2003) Vaccine safety. Immunol Allergy Clin N Am 23:589–603
Patja A, Davidkin I, Kurki T, Kallio MJ, Valle M, Peltola H (2000) Serious adverse events after measles–mumps–rubella vaccination during a fourteen-year prospective follow-up. Pediatr Infect Dis 19:1127–1134
Mansoor O, Pillans PI (1997) Vaccine adverse events reported in New Zealand 1990–1995. NZ Med J 110:270–272
D’Souza RM, Campbell-Lloyd S, Isaacs D, Gold M, Burgess M, Turnbull F, O'Brien E (2000) Adverse events following immunisation associated with the 1998 Australian measles control campaign. Commun Dis Intell 24:27–33
Lawrence G, Menzies R, Burgess M, Wood N, Boyd I, Purcell P, Isaacs D (2003) Surveillance of adverse events following immunisation: Australia, 2000-2002. Commun Dis Intell 27:307–323
Lawrence G, Boyd I, McIntyre P, McIntyre P, Isaacs D (2004) Surveillance of adverse events following immunisation: Australia 2002 to 2003. Commun Dis Intell 28:324–338
Lawrence G, Boyd I (2005) Supplementary report: surveillance of adverse events following immunisation among children aged less than 7 years in Australia, 1 January to 30 June 2005. Commun Dis Intell 29:413–416
Lawrence GL, Aratchige PE, Boyd I, McIntyre PB, Gold MS (2007) Annual report on surveillance of adverse events following immunisation in Australia, 2006. Commun Dis Intell 31:269–282
Lawrence G, Gold MS, Hill R, Deeks S, Glasswell A, McIntyre B (2008) Annual report: surveillance of adverse events following immunisation in Australia, 2007. Commun Dis Intell 32:371–387
Aagaard L, Weber CB, Hansen EH (2010) Adverse drug reactions reported for children in Denmark from 1998–2007. Drug Saf 33:327–339
Aagaard L, Hansen EH (2010) Adverse drug reactions from psychotropic medicines reported for children 1998–2007: a national register-based study from Denmark. BMC Res Notes 23(3):176
Aagaard L, Hansen EH (2010) Adverse drug reactions reported for systemic antibacterials in Danish children over a decade. Br J Clin Pharmacol 70:765–768
The Danish National Board of Health. The children’s vaccination schedule in Denmark, 2009. Available at: (http://www.sst.dk). Accessed 3 June 2010
Summary of product information. MFR vaccine. Available at: (http://www.smi.dk). Accessed 3 June 2010
Summary of product information. Ditekipol/Act-Hib vaccine. Available at: (http://www.smi.dk). Accessed 3 June 2010
Aagaard L, Stenver DI, Hansen EH (2008) Structures and processes in spontaneous reporting systems: a comparative study of Australia and Denmark. Pharm World Sci 30:563–570
Roden S, Gibbs T (2007) CIOMS Working Groups and their contribution to pharmacovigilance. In: Mann RD, Andrews EB (eds) Pharmacovigilance, 2nd edn, chapter 23. John Wiley & Sons, Chichester, pp 287–305
MedDRA. Available at: http://www.meddramsso.com (last accessed June 3 2010) [password required]
Pharmacovigilance: medicinal products for human use and veterinary products, vol. 9. Available at: http://ec.europa.eu/enterprise/pharmaceuticals/eudralex/homev9.htm. Accessed 3 April 2010
Infomedia. Available at: http://www.infomedia.dk. Accessed 20 November 2009
Glissman S (2005) Danish Supreme Court rules that child with autism developed in temporal relation with MMR vaccination is not entitled to compensation. Euro Surveill 10:E050428.3
Hviid A, Stellfeld M, Wohlfahrt J, Andersen PH, Melbye M (2006) The impact of pre-school booster vaccination of 4–6-year-old children on pertussis in 0–1-year-old children. Vaccine 27:1401–1407
Aagaard L, Hansen EH (2009) Information about ADRs explored by pharmacovigilance approaches: a qualitative review of studies on antibiotics, SSRIs and NSAIDs. BMC Clin Pharmacol 3(9):4
Woo EJ, Ball R, Burwen DR, Braun MM (2008) Effects of stratification on data mining in the US Vaccine adverse event reporting system (VAERS). Drug Saf 31:667–674
Acknowledgements
We would like to thank the Danish Medicines Agency for placing data at our disposal.
Conflict of interest statement
We have no conflicts of interest to declare.
Contributors
LA, EWH and EHH designed the study, analysed data and wrote the first version of the manuscript. LA did the sampling. All authors saw and approved the final version of the manuscript.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Aagaard, L., Hansen, E.W. & Hansen, E.H. Adverse events following immunization in children: retrospective analysis of spontaneous reports over a decade. Eur J Clin Pharmacol 67, 283–288 (2011). https://doi.org/10.1007/s00228-010-0944-9
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00228-010-0944-9