Assessment of susceptibility and immunity to vaccine preventable infectious diseases according to vaccination status: a prospective analysis

Infectious Diseases (IDs) represent a public health concern, even in countries where the implementation of vaccination programs has reduced the disease burden of many life-threatening IDs. Monitoring the immunity level of a population is of utmost importance to identify possible pockets of susceptible people and high-risk groups. The assessment of the seroprevalence profile in a population helps public health authorities to address new vaccination strategies. Results of serological surveys in comparison with vaccination coverage available data provide essential information used as indicators for the achievement of the National Plan objectives. The aim of this project is to assess the immunity to some vaccine preventable IDs in a sample of sera collected from the resident population in Florence, through serological surveys (test ELISA) and to provide a descriptive statistical analysis of the results. Previous sero-epidemiological studies performed in the same population could be useful for the assessment of the immunity trend in specific age groups. The originality of this study is a questionnaire which collects anamnestic and immunisation records of the participants, to identify the acquired (natural or by vaccination) immunity against IDs. The serological results will be analysed by Bayesian mixture models to distinguish groups with different degrees of immunity.