Spontaneous reports of vaccination errors in the European regulatory database EudraVigilance: A descriptive study

Among all post-marketing medication error reports submitted to EudraVigilance, vaccines are the most frequently reported medicinal products. This study aims to describe the characteristics of vaccination errors submitted to Eudravigilance between 2001 and 2016.

EudraVigilance is a spontaneous reporting database for adverse events maintained by the European Medicines Agency. We extracted Individual Case Safety Reports (ICSRs) submitted to EudraVigilance between 1 January 2001 and 31 December 2016. Reports were included for analysis if a vaccine was reported as interacting or suspect drug and at least one medication error term was listed as an adverse reaction. ICSRs were stratified by age and gender, by year of reporting, region of origin, reporter profession, seriousness of outcome, ATC, and type of error.

In total, 7097 ICSRs were included in the study. We observed a yearly increase in the reporting of vaccination errors, with the proportion to all vaccine ICSRs increasing from 0.4% to 4.0% between 2001 and 2016. The majority of reports was classified as serious (4248, 59.9%), but non-serious reports were increasingly reported since 2012. The mean age of patients was 24.1 years. The most frequently reported vaccines were influenza (13.5%), bacterial and viral combined (12.3%), and hepatitis vaccines (11.8%). A total of 8167 medication error terms were reported. The most frequently reported terms were "Inappropriate schedule of drug administration" (27.2%), "Incorrect route of drug administration" (12.5%) and "Drug administered to patient of inappropriate age" (10.0%). For infants and children, the error "Drug administered to patient of inappropriate age" was reported more often than for all other age categories.

Vaccination errors are increasingly submitted to EudraVigilance. Errors related to the schedule are the most common errors reported with vaccines. However, consequences of vaccination errors appear to be relatively mild.