Coxiella burnetii and HIV infection in people experiencing homelessness.

This study has investigated Coxiella burnetii and HIV infection among the persons experiencing homelessness of São Paulo city, Brazil, and assessed correspondent associated risk factors. A cross-sectional study was carried out with 203 individuals performing serological tests for anti-C. burnetii and anti-HIV antibodies. A prevalence of 14.8% (30/203) was found for anti-C. burnetii IgG antibodies, with titers ranging from 64 to 1024, while anti-HIV seroprevalence was 6.4% (13/203). No statistical association was found between C. burnetii and HIV seropositivity, or between seropositivity and assessed clinical and epidemiological variables. The findings herein highlight the high homelessness exposure to Q fever, possibly influenced by environmental factors such as dust aerosols, stray animal interactions and unsanitary living conditions. To the authors knowledge, this is the first serosurvey of C. burnetii in persons experiencing homelessness to date. The study herein has emphasized the importance of public health strategies targeting vulnerable populations, particularly in Brazilian major cities. Further C. burnetii surveys should be conducted to establish whether transmission may occur in other persons experiencing homelessness worldwide.