Facteurs associés à la détection de Coxiella burnetii dans les prélèvements de poussière en élevages de ruminants domestiques

Abstract

Q fever is an abortive disease of ruminants aerially transmitted by environmental dust contaminated by abortion or parturition products and by faeces. Nevertheless, the relationship between the occurrence of abortions and environmental contamination remains poorly understood. The aim of our study was to estimate Coxiella burnetii's detection frequency and bacterial loads in environmental dust from farm buildings and to determine whether this environmental contamination was associated with the occurrence of abortive episodes attributed to Q fever. Dust samples (n=109) were collected from cattle, sheep and goat farms suspected or not for clinical Q fever. Many of them were positive by quantitative PCR. The probability to detect C. burnetii's DNA was higher on goat or sheep farms than on cattle farms, and on farms suspected for clinical Q fever than on non-suspected farms. Dust from farm buildings might therefore be an indicator of the status of herds regarding Q fever.