Background. Q fever is the one of the best-studied zoonoses, which is widespread throughout almost the entire territory of Africa, excluding the territory of the Sahara. However, the current data on the incidence of coxiellosis and the circulation of Coxiella burnetii on this continent are limited and vary according different sources. In 1980–1990, the Soviet-Guinean Research Virology and Microbiology Laboratory conducted studies to estimate the distribution of the Q fever pathogen, assess the herd immunity in humans and identify specific antibodies in the sera of livestock. However, in subsequent years, the research was suspended. The aim of this study is to obtain up-to-date data on the distribution of C. burnetii in all landscape and geographical zones of the Republic of Guinea. Materials and methods. The study was carried out in the laboratory of the Russian-Guinean Center for Epidemiology and Prevention of Infectious Diseases (Kindia, Republic of Guinea). The study involved 332 sera of febrile patients and 3156 sera from practically healthy volunteers, 1074 blood samples of livestock, 1648 suspensions of ticks, 319 specimens of small mammals and 298 of bats. The study was carried out using ELISA and PCR methods, selected samples were subjected to in-depth genetic analysis. Results and discussion. The study of the distribution of C. burnetii on the territory of all landscape-geographical zones of the Republic of Guinea was carried out. For the first time, an officially registered case of human Q fever case has been identified. The role of livestock, small mammals and bats in the circulation of the pathogen has been established. It has been shown that the main vectors in Guinea are ixodid ticks of the Amblyomma variegatum, Hyalomma truncatum and Rhipicephalus decoloratus species. Employing molecular methods, C. burnetii strains carrying the QpH1 plasmid, capable of causing diseases in humans and animals were identified. For the first time, the complete nucleotide sequence of 16S rRNA of the Q fever pathogen (OQ152497–OQ152500) identified on the territory of Guinea was determined and registered in the GenBank database. Conclusion. Taking into account the high epidemiological significance of Q fever, the study of the specifics of C. burnetii circulation in Guinea remains an urgent task. Regular monitoring and assessment of risk factors for diseases caused by coxiella are necessary for the development of an algorithm for laboratory diagnosis and recommendations for clinicians.
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