Detection of Q-fever in Samarkand region of Uzbekistan: mite surveillance study
Abstract
Purpose: The worldwide increase in incidence of Q-fever, significant changes in epidemiologic patterns and close proximity of potential endemic areas such as North Asia has led to raised attention to this disease in Uzbekistan. Some clinical cases of patients hospitalized to Samarkand regional hospital with acute fever of unknown origin were diagnosed with Coxiella burnetii using of immune-enzyme analysis (IEA). True prevalence in the region is not clear, due to asymptomatic course of the disease thus making surveillance for C. burnetii in ticks a critical component of control and prevention of this disease. The aim of the study was to identify spread of C. burnetii in ticks collected in Samarkand region of Uzbekistan. Methods & Materials: In 2015, 1200 ticks were collected from domestic animals in the following districts of Samarkand region: Jambay, Taylak, Ishtikhan, Narpay, and Urgut. The collected ticks were divided by species and pooled for grinded suspensions. DNA from supernatant of each pool was extracted using “Ample Prime ®RIBO Sorb” for further testing by PCR on Qiagen Rotor-Gene. Simultaneously, a PCR detection was conducted among patients with acute fever for more than 5 days that were admitted to the Samarkand regional hospital. Results: The results of the study showed that the most common imago mites in Samarkand region were Hyalomma a. anatolicum and H. as. asiaticum. The DNA of C. burnetii was detected in 9.1% of total mite samples in Samarkand region. 155 of Argas persicus specimens (13 pools) and 308 H. asiaticum specimens (14 pools) collected in Narpay district were positive for Q-fever. From Urgut region 96 specimens was Q-fever positive in H. asiaticum mites. In the Ishtikhan region C. burnetii was detected in 96 specimens of H. a. anatolicum mites and in 54 specimens of H. detritum mites. Simultaneously, out of 56 blood serums, the Q-fever was established in 21.4% of cases. Conclusion: Application of Real Time PCR diagnostics shows first detection of C. burnetii among mite population in Uzbekistan that proves their significant role in spread of Q-fever disease and will help increase the effectiveness of epidemiological surveillance of this pathology in the Republic of Uzbekistan.