Coxiella burnetii in bulk tank milk and antibodies in farm workers at Montería, Colombia

Background: Q fever is a zoonotic disease caused by Coxiella burnetii. In Colombia it is not a notifiable disease in humans and is most likely under diagnosed. There are no studies about its prevalence in important reservoir species, such as cattle. Objective: the aim of this study was to investigate the frequency of C. burnetii infection in cattle farms and determine the frequency of antibodies in farm workers at risk in rural areas of Montería, Córdoba (Colombia). Methods: eleven cattle farms were randomly chosen to investigate the infection by C. burnetii. Bulk tank milk samples of each farm were analyzed by conventional PCR for DNA detection of transposase gene IS1111 of C. burnetii. Serum samples from 61 apparently healthy people living in eight farms were analyzed by indirect inmunofluorescence against phase II IgG antibodies to C. burnetii. Results: we report the presence of C. burnetii DNA in 45% of bulk tank milk samples from cattle farms and a 61% frequency of antibodies (IgG phase II ≥1/64) in farm workers at risk. Conclusion: our results demonstrate the circulation of this bacterium in the studied farms in Montería, Colombia, showing that at-risk farm workers have a high antibody frequency