Prevalence of Acute Q Fever Among High-Risk Patients With Fever and Pneumonia Symptoms in Western Iran

Background: Q fever is a zoonotic bacterial infection with worldwide distribution. Based on seroepidemiology studies among the human population and also serological and molecular surveys of animals, Q fever is an endemic disease in Iran. However, the status of acute Q fever in many parts of Iran is still unknown. This study aimed to investigate acute Q fever among high-risk patients with fever and pneumonia symptoms in Western Iran. Methods: In this survey, 96 patients were included in the study in Kurdistan Province who had symptoms of suspected pneumonia or acute Q fever and epidemiological evidence for the risk of Q fever. From each individual, paired acute and convalescent serum samples were taken, and the elevation of the phase II IgG antibody titer against Coxiella burnetii was traced by ELISA. Also, molecular detection of C. burnetii was done in acute blood samples by real-time PCR. Results: Seven patients (7.3%) were diagnosed with acute Q fever who had seroconversion and a four-fold rise in the phase II IgG antibody titer against C. burnetii in their paired sera samples. Also, 22 of 89 (24.7%) individuals with a negative result for acute Q fever had a previous history of exposure to C. burnetii. There was a significant relationship between sheep husbandry and a previous history of exposure to C. burnetii (p=0.04). All molecular tests were negative. Conclusion: The results of this study showed that there are cases of acute Q fever in Western Iran, but it is not considered by the healthcare system or clinicians.