Objectif. To assess the prevalence of pneumococcal nasopharyngeal carriage, the role of potential risk factors, and vaccination against invasive pneumococcal diseases (IPD) among sheltered homeless persons (HP) in Marseille, France.
Methods. In 2015–2018, we enrolled 571 sheltered homeless males and 54 non-homeless controls. Streptococcus pneumoniae was directly searched form nasal/pharyngeal samples using PCR.
Results. The HPs were predominantly middle-aged, mostly migrants originating from African countries. Pneumococcal vaccination rate was low (3.1%). The overall pneumococcal carriage rate was 13.0% and was significantly higher in HPs (15.3% in 2018) than in controls (3.7%), with p=0.033. Among HPs, being aged ≥65 years (OR=1.97, p=0.048), living in one specific shelter (OR=1.80, p=0.028), and presenting respiratory symptoms and signs at the time of enrolment (OR=2.55, p<10-4) were independent factors associated with pneumococcal carriage.
Conclusion. Pneumococcal vaccination should be systematically considered for sheltered HPs in France, as has been the case in Canada since 2008.
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