Vaccine risk assessment in children with a referred reaction to a previous vaccine dose: 2009–2011 retrospective report at the Bambino Gesu’ children hospital, Rome, Italy

BACKGROUND During the last century, mass vaccination programs have achieved considerable success across the world in immunizing against several serious infectious diseases. However, vaccinations are threatened by their own success after results have been obtained: the more the incidence of potentially devastating diseases decreases, thanks to the success of vaccination programs, the more public attention shifts towards real or alleged "side effects" of vaccines. METHODS We analyze the experience of 153 children with "reaction to a previous vaccine dose" continuing the vaccination protocol in the safe environment of the Center for risk vaccination at the Bambino Gesù Children's Hospital IRCCS in Rome, from 2009 to 2011. RESULTS To assess the suitability for vaccination, a specialized pre-vaccination advice and a skin prick test (SPT) was undergone, according to Wood's guideline; 151 children were SPT negative and full vaccine was administered. Of the 153 children examined just 13 had symptoms suggestive of IgE-mediated reaction-type reactions with angioedema manifestations. Among them, 2 had positive STP, which required alternative measures of administration of the vaccine. No cases of post vaccination reaction was reported and no vaccination program was stopped due to a severe reaction. CONCLUSIONS Inadequate levels of immunization against infectious diseases remain a significant problem for public health. However, the reasons for incomplete vaccination and non-adoption of vaccination services are manifold. To maintain public confidence in vaccines, advanced immunization programs must include activities for monitoring the safety of the vaccine at the individual level and pursuing specialized counseling pre-and post-vaccination for those at risk. Our results underlined a gap between true and referred adverse reactions and are consistent with vaccine safety. Anyway, a continuous assessment of the risks and benefits of vaccination is required and the results must be disclosed in order to strengthen confidence in the existing and in the new immunization programs.