Coxiella burnetii (Q fever) exposure in recycling, non-recycling workers and dogs in a major urban area of Brazil

Introduction: Q fever has been considered a worldwide zoonosis caused by Coxiella burnetii, mostly transmitted by respiratory routes in contaminated environments with bio logical waste. Although urban recycling facilities may concentrate contaminated materials, their significance as potential environmental sources for C. burnetii infection has not been investigated to date. Methods: Accordingly, the aim of this study was to assess previous exposure to C. burnetii in recycling, non-recycling workers and their dogs from Curitiba, a major urban area currently ranked 8th in population with 1.8 million habitants, 7th in Gross Domestic Product (GDP), and 10th in Human Development Index (HDI) out of 5,569 Brazilian cities. Results: In overall, 6/278 (2.15%) workers and 7/137 (5.1%) dogs were seropositive to C. burnetii by indirect immunofluorescence assay (IFA). Discussion: Due to low seropositivity, no risk factor was statistically associated with C. burnetii exposure. This was the first study to investigate C. burnetii infection in workers and dogs of urban recycling centers. Although low, positive cases have suggested likelihood of environmental expo sure to Q fever. Such findings highlight the importance of future investigations, as well as the need to ensure proper use of respiratory protective equipment among recycling workers in major urban areas of Brazil and worldwide.