[Adverse drug reactions following immunization in Germany pursuant to the German Infection Protection Act and the German Medicinal Products Act from January 1, 2004 to December 31, 2005].

Sufficient post-marketing surveillance is necessary for safety monitoring of vaccines. In this respect the spontaneous reporting system of reporting suspected adverse drug reactions (ADR) following vaccination is an essential tool for safety monitoring. The marketing authorization holder and/or pharmaceutical manufacturer has the legal obligation to report suspected adverse drug reactions (German Drug Law and European Regulation). In addition physicians and traditional healers have to report suspected cases of complications after immunizations pursuant to the German Infection Protection Act (Infektionsschutzgesetz, IfSG). The reports are medically assessed and stored in a database at the Paul Ehrlich Institute. For the publication referenced here, all reported suspected cases of adverse drug reactions after immunizations were evaluated for the period from January 1, 2004-December 31, 2005 according to different criteria. In 2004 (2005) a total of 1237 (1393) suspected cases of adverse drug reactions or suspected complications after immunizations were notified. 858 (919) of these adverse drug reactions (ADR) were serious (69 % and 66 %, respectively). 414 (517) of the ADRs (i.e. 33 % and 37 %, respectively) were reported by physicians according to the IfSG; the other reports were from industry and other reporting sources. 251 (229) i.e. 61 % (44 %) of these reactions were serious. The total number of reports divided by the total number of vaccine doses launched on the German market during the observation period (according to the data provided by the pharmaceutical industry) revealed an overall "reporting rate" of approx. 3 reports per 100,000 vaccine doses. The age groups with the highest absolute number of reported cases were infants and young children (0-2 years), and adults (18-59 years) accounting for approx. one third each of the reports. The age distribution of the suspected cases was comparable with that of previous years. In both years, approx. half of all suspected adverse drug reactions following immunization were of transient nature, i.e. there was a complete recovery (restitution ad integrum). In both years, a very small proportion of cases were reported as permanent damage (30 and 34 cases respectively; 2.4 % of all cases) or resulted in death (35 or 23 cases, respectively; 2.8 % or 1.7 %, respectively). With a few exceptions these adverse events were considered to be related to other diseases and unlikely related to vaccination. Overall, the association between vaccination and adverse events was assessed by the PEI as "possible" in 58 % (62 %) of all cases, respectively, as "likely" in 6 % (8 %) of all cases, and as "certain" in 0.4 % (0.6 %) of all cases. In 14 % (13 %) of the cases, the causal relation was stated as "unlikely". In 17 % (15 %) of all cases, a scientific evaluation was not possible on the basis of the data provided. A separate analysis of reports was conducted for all suspected adverse drug reactions following varicella immunization. According to these data varicella vaccination is considered to be well tolerated. With the exception of an increase in local reactions following pneumococcal polysaccharide vaccination no new safety signal has been recognised during the observation period.