Q fever is a zoonotic rickettsial disease. The most common animal reservoir for Q fever is cattle, sheep and goats. These animals when infected shed the organism in urine, feces and especially, in birth products. Q fever has been reported from all continents and is endemic in areas where reservoir animals are present. It is known that the active transmission of infection occurs in humans in direct contact with agricultural animals and their products.

In Ukraine, Q fever occurs in all geographical landscape zones and in most administrative regions of the Ukraine. The disease has been recently introduced in the middleeastern, southern and southwest parts of Ukraine. Multiple natural and mixed foci of Q fever have been demonstrated in 19 administrative regions of Ukraine, AR Crimea and Sevastopol city, and Coxiella burnetii strains have been isolated from small animals and ticks.

The article is devoted to the issue of the prevalence of Q-fever on the three rural sites with different landscape-climatic conditions. There is no preview data about spreading of Coxiella burnetii among population on the investigated sites but prevalence or incidence data for Q fever could be under- or over-estimated due to similarity in clinical symptoms with other zoonotic diseases. We conduct study on the area with favorable conditions for occurring of the natural foci of tick-borne transmission diseases.

The aim of the study was to conduct laboratory-based surveillance for estimation of the prevalence of Q-fever among rural population in three sites and provide useful information on the geographical distribution and ecology of this disease.

Study subjects were recruited from residents of the sites by age over 5 years old.

There was no gender exclusion. Any individual or his/her parent or guardian who agreed to prarticipate informed about their consent through his/her signature (thumbprint) on the consent form. Each study participant was assigned a unique identification number (ID) that will be used to ensure confidentiality during the study and analysis of the surveillance data. The ID number was included on all of the participant’s questionnaires and samples. It was difficult to calculate the sample size for study in sites since there is no available prevalence data.

The study was carried out in thee steps. During the first step all serum sample collections, epidemiological and ecological investigations was done.

During the second step serum samples collected from recruited persons were tested using an ELISA IgG capture assay for Q-fever (ELISA-anti-Q, Pastera FS SRIEM Rospotrebnadzor, S.-Petersburg, RF).

It was set that Q-fever is an endemic disease on each investigated site. Antibodies for agent were detected for 13 (13,0±3,4)% (participants from site “A”), 11 (8,1±2,3)% – site “Б”, and 4 (3,2±1,6) % – site “В”.

Only infected persons were adult. In site “A” were detected seropositive persons by age 32-66 (average – 53,0) with no gender difference. Age of seropositive investigated recruits in site “Б” were 18–75 (average – 42,5 ), and “В” – 25–46 (average – 40,0) and mainly male for both.

In three cases infections of two or more family members were detected. Analysis of epidemiological databases allow to confirm domestic risk infection predominantly which mostly could be related to the care of livestock, use of crude milk and dairy products.

Prevalence case rates were 14,2 (site A); 10,2 (site Б); and 14,8 (site B) per 100000 population.

Thus, based upon a cohort seroepidemiological studies in three rural areas seropositive individuals to Coxiella burnetii have been identified, which indicates the endemicity area of Q-fever.

Keywords: Q-fever, prevalence, rural population

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