STUDII OBSERVAŢIONALE DE EVALUARE A EFICIENŢEI VACCINĂRII GRIPALE LA VÂRSTNICI DERULATE ÎN BUCUREŞTI.

Influenza prevention through the seasonal flu vaccine in elderly population remains an efficacious method, in spite of the fact that not always the vaccine confers enough protection in the elderly. In current literature reviews it has been demonstrated that antibody response to the flu vaccination in the elderly is significantly lower than in young population, with an ever-lower response in the people over 75 years old. The aim of this study is to evaluate the efficiency of influenza vaccination in elderly population from Bucharest, in three observational studies that have run in three different seasons: 2006/07; 2007/08 and 2010/11. In this way, we have analyzed the vaccine response through measuring some serological parameters: the rate of increasing of antibody geometric mean, seroprotection and seroconversion, for each vaccine component (H1, H3 and B), in accordance with accepted criteria of European Medicines Agency (EMA) for age group ≥ 60 years. Also, we have compared the immune response in subgroups of young elderly (60-74 years) versus old elderly (≥75 years), for bringing new clarifications in relationship between age impact and vaccine response. Values lower than threshold recommended by EMA was obtained in season 2007/08 in seroprotection and seroconvertion for strain B/Malaysia and in the season 2010/11 in seroprotection for strain B/Brisbane, suggesting that the immune response for these vaccine components were inadequately in the elderly. In all three seasons there were respected EMA criteria (at least one parameter per strain to be in recommended limits), so by using serological endpoints, vaccinations in the elderly were efficacious in all three seasons. Age subgroup analyze has found no significant statistic differences in immune response in any season. [ABSTRACT FROM AUTHOR]