Detection of Coxiella burnetii and Borrelia spp. DNA in Cutaneous Samples and in Household Dust in Rural Areas, Senegal

Q fever and tick-borne borreliosis are two zoonotic diseases rarely diagnosed in Senegalese health facilities, particularly in rural areas. Our study aims to better understand the circulation of Coxiella burnetii and Borrelia spp. DNA on human skin and the domestic environment in rural areas. Cutaneous swabs were taken from febrile patients being treated for borreliosis and/or Q fever, the members of patients' households and control households in the Niakhar area. Dust samples were also collected from 90 households where 54 cases of borreliosis and Q fever were reported as well as from the households of members of control populations in Dielmo, Ndiop, and Niakhar. C. burnetii and Borrelia spp. DNA were detected by quantitative PCR in cutaneous swabs and dust samples targeting spacers IS1111_IS30A and Bor 16S gene. Of 1365 persons tested, 76 were shown to carry C. burnetii, 13 Borrelia spp., and 6 were identified as carrying both C. burnetii and Borrelia spp. The prevalence of Borrelia spp. DNA in households was 16.7% in Dielmo, 6.7% in Ndiop, and 23.3% in all other villages in the Niakhar area, and the presence of C. burnetii in the same localities was 10%, 13.3% and 66.7%, respectively. Furthermore, C. burnetii genotyping identified the presence of Multispacer Sequence Typing group 6. These results revealed for the first time the carriage on the skin of C. burnetii and Borrelia spp. DNA in humans and its wide distribution across households. Our findings suggest that many populations are exposed to these diseases, with frequent contaminating cases of infectious origin arising from the domestic environment.

Chemical characterization of indoor and outdoor fine particulate matter in an occupied apartment in Rome, Italy

The daily concentration and chemical composition of PM2.5 was determined in indoor and outdoor 24-h samples simultaneously collected for a total of 5 weeks during a winter and a summer period in an apartment sited in Rome, Italy. The use of a specifically developed very quiet sampler (<35 dB) allowed the execution of the study while the family living in the apartment led its normal life. The indoor concentration of PM2.5 showed a small seasonal variation, while outdoor values were much higher during the winter study. Outdoor sources were found to contribute significantly to indoor PM concentration especially during the summer, when the apartment was naturally ventilated by opening the windows. During the winter the infiltration of outdoor PM components was lower and mostly regulated by the particle dimensions. Organics displayed In/Out ratios higher than unity during both periods; their indoor production increased significantly during the weekends, where the family stayed mostly at home. PM components were grouped into macrosources (soil, sea, secondary inorganics, traffic, organics). During the summer the main contributions to outdoor PM2.5 came from soil (30%), secondary inorganics (29%) and organics (22%). Organics dominated both indoor PM2.5 during the summer (60%) and outdoor and indoor PM2.5 during the winter (51% and 66%, respectively).

Survey of the reliability of carbon monoxide alarms deployed in domestic homes and efficacy of use by consumers

Carbon monoxide (CO) alarms are extensively used in domestic premises in the UK to help protect against CO poisoning. Their expected lifetime has been increasing, and some current models now have a replacement period of more than 6 years under normal operation. However, concerns have been expressed as to the reliability of alarms over an extended period. In this study, 110 households with a CO alarm were surveyed, during which the alarm was uninstalled and replaced and a household survey questionnaire administered. Alarm reliability was assessed under laboratory conditions by testing conformity to the alarm condition gas tests in either the British (European) standard, BS EN 50291 for UK certified models, or the US standard, UL 2034 for US certified models. The questionnaire recorded the alarm make and model, its age, its location, whether it was correctly sited, and how often it was tested. General information on the property was also collected. Results of laboratory testing suggest that the reliability of the most common models of CO alarms used by UK consumers has improved over the last 7 years. However, findings from the household survey suggest that the way alarms are used in many homes may not maximize their ability to detect abnormal levels CO.