Klinik insan vakaları, klinik olmayan hayvan vakaları ve farklı gıdalardaki salmonella çeşitliliğinin vuruşlu alan jel elektroforezi (PFGE) kullanılarak moleküler düzeyde belirlenmesi.


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Türkiye

Tezin Onay Tarihi: 2014

Tezin Dili: İngilizce

Öğrenci: Ece Bulut

Eş Danışman: GÜLAY ÖZCENGİZ, YEŞİM SOYER

Özet:

Salmonella is one of the most reported pathogens in foodborne outbreaks worldwide. In order to ensure safety of foods, farm-to-fork surveillance and control systems must be utilized. Development of numerous typing methods have improved the ability to detect salmonellosis outbreaks, enabling to trace the contaminated source from farm to fork. Facilitating prevention and regulation of techniques, knowledge of the epidemiology, genetics and ecology of Salmonella infections depend on the information provided by typing methods. In this study a phenotypic subtyping method, serotyping, and the current “gold standard” molecular subtyping method for bacterial pathogens, pulsed-field gel electrophoresis (PFGE) was used for characterization of 59 isolates of food origin, 53 isolates of animal origin and 50 clinical human isolates collected from Şanlıurfa region. Salmonella was prevalent mostly in chicken and offal samples (58.3 %), while Salmonella isolates from positive samples were much diverse in animal feces. Paratyphi B was the main serovar recorded for clinical human isolates; serovars Enteritidis, Typhimurium and Kentucky were recovered from all three sources. Having the most diversity from both typing methods, 53 animal isolates were represented by 13 subsp. enterica serovars and subspecies diarizonae and salamae; moreover, 28 PFGE types were observed. For all isolates, PFGE (SID: 0.975) represented a higher discriminatory power with respect to serotyping (SID: 0.915); serovar Montevideo had the most variation with 8 different PFGE types. The results were uploaded to a publicly available databanks (Food Microbe Tracker: http://www.foodmicrobetracker.com/login/login.aspx and Pathogen Detector: pathogendetector-metu.rhcloud.com); therefore, the information could be useful for investigations on farm-to fork chain, as well as for evolution, ecology and transmission of Salmonella in Turkey. From our knowledge, this is the first study reporting Salmonella diversity through farm to fork chain in the same period of time and at the same location in Turkey.