Publication: İstanbul'da ixodes ricinus türü kenelerde lyme borreliozis varlığı, yayılışları ve biyogüvenlik riskleri
Abstract
Amaç: Lyme Borreliozis, ABD ve Avrupa’da en fazla görülen kene kaynaklı hastalıklardan birisi olup, Ixodes ricinus tür kompleksine ait keneler tarafından aktarılmaktadır. Türkiye’de de bu tür kompleksine ait kenelerin varlığı bilinmekte ve İstanbul’da da sıklıkla karşılaşılmaktadır. İstanbul’da kene tutma vakalarının en büyük sorumlusu I. ricinus tür kompleksine ait kenelerdir. Bu tezde İstanbul’daki I. ricinus tür kompleksine ait kenelerde Lyme borreliozis (LB) etkeni olan Borrelia burgdorferi sensu lato (s.l.) bakterisinin moleküler yöntemler ile aranması ve bölgedeki Lyme borreliozis risk durumunun belirlenmesi amaçlanmıştır. Gereç ve yöntem: Tez çalışması için belirlenen bölgelerde bahar ve yaz aylarında bayraklama yöntemi ile kene örnekleri toplanmış, morfolojik tür tayinleri gerçekleştirilmiş ve DNA ekstraksiyonları gerçekleştirilmiştir. Elde edilen DNA’lar ve B. burgdorferi s.l. özgü 16s rRNA, 5s-23s ITS ve flaB geni primerleri kullanılarak PCR işlemi gerçekleştirilmiştir. Seçilen PCR ürünleri Sanger DNA dizileme yöntemi ile dizilenmiştir. Elde edilen veriler kullanılarak B. burgdorferi s.l. türleri filogenetik ağaçta gösterilmiştir. Bulgular: Elde edilen bulgulara göre toplanan I. ricinus türü kenelerde, B. burgdorferi s.l. gen bölgelerine göre %32,84-22,39 olmak üzere değişen oranlarda B. burgdorferi s.l. pozitifliği elde edilmiştir. Dizi analizi ve filogenetik ağaç sonuçlarına göre seçilen pozitif örneklerin tamamının LB ile ilişkili grupta olduğu belirlenmiştir. Sonuç: Bu tez çalışması ile İstanbul ilinde geniş alanda yapılan kene örneklem çalışması sonucunda bölgenin LB riski altında olduğu belirlenmiştir. Ayrıca B. burgdorferi s.l. içinde bulunan B. turdi Türkiye’de ilk kez rapor edilmiştir.
Objective: Lyme borreliosis is one of the most common tick-borne diseases in the USA and Europe and is transmitted by ticks belonging to the Ixodes ricinus species complex. Although the existence of ticks belonging to this species complex is known in Turkey, they are frequently encountered in Istanbul. In addition, ticks belonging to the I. ricinus species complex are most responsible for tick infestations in Istanbul. In this thesis, it was aimed to search for the bacterium Borrelia burgdorferi sensu lato (s.l.), which is the causative agent of Lyme borreliosis (LB) in ticks of the I. ricinus species complex in Istanbul, by molecular methods and to determine the risk status of Lyme borreliosis in the region. Material and methods: Tick samples were collected by the flagging method in the spring and summer months in the regions determined for the thesis study, morphological species determinations were carried out and DNA extractions were carried out. PCR was performed using by B. burgdorferi s.l. specific 16s rRNA, 5s-23s ITS and flaB gene primers and obtained DNAs. Selected PCR products were sequenced using the Sanger DNA sequencing method. Using the obtained data, B. burgdorferi s.l. species are shown in the phylogenetic tree. Results: According to the findings, B. burgdorferi s.l positivity was obtained at varying rates, 32.84%-22.39%, according to the B. burgdorferi s.l gene regions, in the collected I. ricinus ticks. According to sequence analysis and phylogenetic tree results, it was determined that all of the positive samples selected were in the group associated with LB. Conclusion: As a result of the tick sampling study conducted in a large area in Istanbul with this thesis study, it was determined that the region is under the risk of LB. In addition, B. turdi in B. burgdorferi s.l species was reported for the first time in Turkey.
Objective: Lyme borreliosis is one of the most common tick-borne diseases in the USA and Europe and is transmitted by ticks belonging to the Ixodes ricinus species complex. Although the existence of ticks belonging to this species complex is known in Turkey, they are frequently encountered in Istanbul. In addition, ticks belonging to the I. ricinus species complex are most responsible for tick infestations in Istanbul. In this thesis, it was aimed to search for the bacterium Borrelia burgdorferi sensu lato (s.l.), which is the causative agent of Lyme borreliosis (LB) in ticks of the I. ricinus species complex in Istanbul, by molecular methods and to determine the risk status of Lyme borreliosis in the region. Material and methods: Tick samples were collected by the flagging method in the spring and summer months in the regions determined for the thesis study, morphological species determinations were carried out and DNA extractions were carried out. PCR was performed using by B. burgdorferi s.l. specific 16s rRNA, 5s-23s ITS and flaB gene primers and obtained DNAs. Selected PCR products were sequenced using the Sanger DNA sequencing method. Using the obtained data, B. burgdorferi s.l. species are shown in the phylogenetic tree. Results: According to the findings, B. burgdorferi s.l positivity was obtained at varying rates, 32.84%-22.39%, according to the B. burgdorferi s.l gene regions, in the collected I. ricinus ticks. According to sequence analysis and phylogenetic tree results, it was determined that all of the positive samples selected were in the group associated with LB. Conclusion: As a result of the tick sampling study conducted in a large area in Istanbul with this thesis study, it was determined that the region is under the risk of LB. In addition, B. turdi in B. burgdorferi s.l species was reported for the first time in Turkey.