Homeless people are often exposed to unhygienic environments as well as to animals carrying arthropods which both transmit zoonotic infections and human louse-borne pathogens. We attempted to determine the prevalence of antibodies against several vector-borne and zoonotic pathogens among homeless adults living in Marseille. During the 2005–2015 period, we collected sera samples from 821 homeless adults living in shelters. Antibodies against Bartonella quintana, Bartonella henselae, Borrelia recurrentis, Coxiella burnetii, Francisella tularensis (with a cut-off of 1:100), Rickettsia akari, Rickettsia conorii, Rickettsia felis, Rickettsia prowazekii, and Rickettsia typhi (with a cut-off of 1:64) were searched by microimmunofluorescence (MIF). MIF-positive serum samples were confirmed by cross-adsorption to characterise cross-reacting antigens and immunoblotting. Positive sera by Western blot were further tested using qPCR. We evidenced a prevalence of 4.9% seroreactivity to at least one pathogen including phase II C. burnetii (2.1%), B. quintana (1.7%), R. conorii (0.4%), R. prowazekii (0.4%), R. typhi (0.1%), B. recurrentis (0.1%), and F. tularensis (0.1%). No DNA from any pathogens was detected. A comparison with studies conducted prior to the 2000–2003 period showed a decrease in the overall seroprevalence of several vector-borne and zoonotic infections.

无家可归的人经常暴露于不卫生的环境以及携带节肢动物的动物，节肢动物既传播人畜共患疾病又传播人虱子病原体。我们试图确定在马赛无家可归的成年人中针对几种媒介传播和人畜共患病原体的抗体的患病率。在2005–2015年期间，我们收集了821名居住在庇护所中无家可归的成年人的血清样本。针对抗体巴尔通体，汉赛巴尔通体，疏螺旋体属recurrentis，贝氏柯克斯体，土拉弗朗西斯菌（具有截止的1：100），立克次体明利，立克次氏体conorii，立克次氏体蚤，通过微免疫荧光（MIF）搜索了立克次体立克次体和伤寒立克次体（截止为1:64）。通过交叉吸附确定MIF阳性血清样品，以表征交叉反应抗原和免疫印迹。使用qPCR进一步测试通过Western印迹检测到的阳性血清。我们证实4.9％seroreactivity的患病率至少一种病原体包括相II贝氏柯克斯（2.1％），B.通体（1.7％），R. conorii（0.4％），R. prowazekii（0.4％），R.伤寒沙门氏菌（0.1％），B. recurrentis（0.1％），和土拉弗朗西斯菌（0.1％）。没有检测到任何病原体的DNA。与2000-2003年之前进行的研究比较表明，几种媒介传播和人畜共患病感染的总体血清感染率有所降低。