Prevalence and risk factors associated with Q fever infection in slaughterhouse workers in Fars province, Iran.

Abstract

Q fever is a main occupational zoonotic disease. Slaughterhouse is one of the most remarkable ways of transmitting the infection from livestock to humans. This study aimed to survey the prevalence of Q fever in slaughterhouse workers in Fars province, Iran, for the first time. Ninety serum samples were collected from slaughterhouse workers and tested to detect Immunoglobulin G (IgG) against Coxiella burnetii using ELISA and indirect immunofluorescence assay (IFA). PCR was also applied to identify C. burnetii DNA in the blood samples. Q fever seroprevalence was found at 26.7% in ELISA, showing recent infection. This result indicates that Q fever seroprevalence is relatively high in the Fars region. IFA showed a high seroprevalence of total IgG antibodies at 1:64 titer (73.3%) and relatively high IgG at 1:256 titer (40%) against C. burnetii. 2.2% of the workers were recognized as having probable acute Q fever. The IgG II prevalence at 1:64 and 1:256 titers was, respectively, 63.3% and 24.4% positive. The IgG I prevalence at 1:64 and 1:256 titers was also found 33.3% and 22.2% positive, respectively. Molecular prevalence of Q fever was also 8.9%. A significant relationship was found between IgG I seropositivity and longer work experience and employing other livestock-related jobs (animal husbandry and butchery) (P < 0.05). As such, the high seroprevalence of Q fever among abattoir workers highlights the importance of further comprehensive epidemiological studies, occupational screening programs, and preventive measures for Q fever in high-risk groups. This also warns animal health care organizations about the risk of Q fever infection in livestock in this region.