OZET Bu calismada Erzurum, Kars ve Agri illerini icine alan bolgede, insan, -koyun ve sigir serumlarinda Q hummasi antikor durumu ve bu hastaligin insan ve hayvanlar arasinda muhtemel yayilma yollari incelenmistir. Bunun icin ·seminlar mikroaglutinasyon metodu ile serolojik testlere tabi tutularak, antikor titreIeri tetkik edilmistir. Koyun ve sigir serumlarinin bir kismi mikroaglutinasyon, kapilar tup aglutinasyonu ve kompleman fik:zasyon metodlari ile ayri ayri muayene edilerek; alinan sonuclar karsilastinlmistir. Sewlojik testlerde pozitif sonuc veren bazi, koyun ve sigir seniinlari kaboylara intraperitonal enjekte edilerek hastaligin etkeni olan Cox.iella burnetii'nin izolasyonuna calisilmistir. Ayrica calisma bolgesinde alti belirli yerde, koyunlardan top~ lanan Dermoseritor cinsi kenelerden Coxiel/a burnetii'nin izole edilmesi denenmistir. Oc ilden toplam olarak 456 koyun ve 262 sigir senimu incelenmi~tir. Koyun serumlarinin %22, i inde, sigir serumlarinin % 15,6 sinda Q hummasi antikoruna raslanilmistir. Incelenen 178 insan serumunda ise %11,2 oramnda Qbummasi pozitif sonuc bulunmustur. Deneme hayvanlarina enjekte edilen Q hummasi antikoni tasiyan serum1ardan, etken izolasyonu mumkun olmamistir. Ancak, kene1er~ den Coxiella burnetii aynimistir. SUMMARY STUDIES ON Q FEVER IN HUMAN, SHEEP AND CATILE IN ERZURUM, KARS AND AGRI PROVINCES A research was conducted to in vestigate the ex.istance of Q fever antibodies in human, sheep and cattle serums' by microagg1utination tests, and probaNe modes of transmission among humen and livestock in Erzurum, Kars and Agri provinces, in Eastem Turkey. In all the tests microagglutination metbodwas used as standart, in addition two other methods namely, capilrary . tube agglutination and complemant fixation were a1so used for some of the serums, and three methods were compared witb one another. In oder to isoIate the microorganism . (C.burnetii), some sheep and cattle serums which yielded positive in serological tests, were inoc.ulated to guinea pigs intraperitoneally. In addition to these for the purpose of isolation of C. burnetii, some ticks be10nging to Dermocentor genus were taken from the sheep, reprasenting the six localities in the region. These ticks were inoculated into guinea pigs intraperItoneally, The anImal serums were collected from Meat and Fish Company, and the Municipal Slougbterhouse of Erzurum, The human serums were obtained from Biochemical Laboratories of Erzurum Numune HospitaI. The antIgens used for the sorological reactions were supplied by Instiutude Pasteur of France. 209 sheep and 108 cattle serums, representing Erzurum area, were examIned and among thern 50 e{23,4) sheep and 13 (% 12,0) cattle serums were found to have Q fever amibodies. 30 (%20,7) out of 146 sheep serums and 18 (%17, i) out of 105 cattle serums from Kars area gave posItive results of Q fever. 21 (%20,6) out of 102 sheep and also LO (%20,4) out of 49 cattle serums were found to be positivc from Agri province. Of the total 456 sheep and 262 cettle serums from the three provinces were tested, and in im (%22,1) sheep and 41 (%15,6) cattle serums, Q fever was ob served as positive. 178 human serums also were tested and 20 (% 11,2) out of them were found to carry Qfever antibodies. In order to compare the three different sero10gical methods, 204 sheep and cattle serums were examined and the results are as fol1ows: 39 (%19,1) serums positive with microagglutin ation, 34 (%16,7) and 36 (%17,6) serums positive with capillary tube agglutination and complament fixation inethods recpectively. On the isolation of C. hurnetii, 38 sheep and cattle serums containing Q fever antbodies were injected into guinea pigs intraperitoneally. No clinical symptoms appeared in these animals during the first one month of the inoculation, but serological tests which were made 30 days later, indicated posttive reactions at the high level in the three guinea pigs. However the microscobic exaininations failed to show the microorganisms in the blood samples of the animals. For iso1ating the agent, suspcnsions from Dermocentor ticks were injected into guinea pigs. During the first month of injections, the animals showed no clinical symptoms, but serological tests gave positive results in one guinea pig. The smears prepared from the blood and spleen of this animal showed rickettsia. T,he rickettsia taken from the blood and s~leen of the animal we,:e isolated in the yolk-sac cu1tures. In addition, social and geographica1 condit ons of the region were discussed as factors effecting the transmIssion of Q fever.