Differences in influenza vaccination coverage among subgroups of adult immigrants residing in Italy at risk for complications (2012-2013)

OBJECTIVES: to evaluate differences in influenza vaccination coverage (IVC) in immigrants at risk for influenza-related complications, according to their area of origin and length of stay in Italy. DESIGN: cross-sectional survey conducted on the sample of foreign citizens included in the survey on health conditions and use of health services of the Italian resident population (Italian national institute of statistics, 2012-2013). SETTING AND PARTICIPANTS: analysis conducted on 885 foreign adult citizens (>= 18 years) at risk for influenza-related complications (elderly residents >= 65 years and residents with specific chronic diseases). MAIN OUTCOME MEASURES: vaccination coverage ratios (VCR) comparison between long-term immigrants (>= 10 years) and recent immigrants (<10 years), and between non-African and African immigrants, adjusted by demographic and sodoeconomic characteristics and level of health services utilization. RESULTS: IVC among immigrants was 15.6%, significantly higher in long-term immigrants (18.3%) compared to recent immigrants (10.2%) (VCR: 1.79; 95%CI 1.21-2.66), and in non-African immigrants (17.1%) compared to African immigrants (9.4%) (VCR: 1.82; 95%CI 1.04-3.17). After adjusting on the basis of demographic and sodoeconomic characteristics and for level of health services utilization between the compared subgroups, the difference in IVC according to the length of stay was greatly reduced (VCR: 1.41; 95%CI 0.94-2.10), while IVC difference reduction according to area of origin was less relevant (VCR: 1.66; 95%CI 0.95-2.91). CONCLUSIONS: demographic and socioeconomic characteristics and level of health services utilization explained part of the difference in IVC between the compared subgroups, particularly between long-term and recent immigrants. The difference in IVC between African immigrants and immigrants from other areas remained quite pronounced even after adjusting on the basis of these factors. This suggests that IVC, especially in African immigrants, is affected by other informal barriers, such as cultural and linguistic barriers, that need to be addressed when planning effective immunization access strategies.