Blastocystis sp.'nin İnsanlara Bulaşında İnsanlarla Yakın İlişkili Hayvanların Rolü

Öz

Blastocystis sp. dünyada yaygın görülen, insanlarda ve hayvanlarda hastalıklara sebep olabilen enterik bir parazittir. Blastocystis sp.'nin genetik çeşitliliği çok fazladır ve günümüzde 17 farklı subtipi (ST) tespit edilmiştir. Bu subtiplerden 9 tanesi insanlarda ve hayvanlarda ortak olduğu için Blastocystis sp.nin insana bulaşında hayvanların etken olabileceği belirtilmiştir. Bu çalışmanın amacı, ülkemizde Blastocystis sp.'nin insanlara bulaşında hayvanların etkisini moleküler yöntemlerle epidemiyolojik olarak araştırmaktır. Çalışmamızda insanlarla yakın ilişkili çeşitli hayvanlardan 420 dışkı örneği toplandı. Bu örnekler trichrome boyama, Jones' medium kültür yöntemi ve Polimeraz Zincir Reaksiyonu (PZR) yöntemi ile çalışıldı. 420 örnekten 53(12.6%)'ünde Blastocystis tespit edildi. Blastocystis sp. pozitif örnekler insana ait subtiplerin tespiti için PZR yöntemi ile çalışıldı. Blastocystis pozitif 53 örnekten 33(62.3%)'ünde (15 Sığır, 14 koyun, 2 tavuk ve 2 at dışkı örneği) 9 Blastocystis subtipinden hiçbiri tespit edilmedi. 20(37.7%) örnekte ise insana ait subtipler tespit edildi. Bu subtiplerin dağılımı şu şekildedir: ST4(7.5%) koyunda ST5, 6(11.3%) tavukta ST6, 11(20.7%) tavukta ST7, 1 tavukta ST6-ST7 beraber tespit edildi. Çalışma sonucunda, ülkemizde sık görülen subtiplerden ST1, ST2, ST3 ve ST4 hiçbir hayvanda tespit edilemedi. Ülkemizde nadir görülen subtiplerden ST5, ST6 ve ST7'nin insana bulaşında koyun ve tavukların kaynak olabileceği değerlendirildi. Sonuç olarak, ülkemizde Blastocystis sp.'nin insana bulaşında zoonotik kaynaklardan çok insanlar sorumlu gözükmektedir.

Anahtar Kelimeler

• Blastocystis sp.
• Moleküler epidemiyoloji
• Polimeraz zincir reaksiyonu.

The Role of Inhabited Animals With People in Human Transmission of Blastocystis sp.

Öz

Blastocystis sp. is a common intestinal parasite worldwide that can cause infection in humans and animals. Blastocystis sp. has a high genetic diversity with 17 different subtypes (ST) identified to date. Since nine of these subtypes are common in both humans and animals, it has been proposed that animals may have a role in the transmission of Blastocystis sp. to human. The aim of this study is to investigate the epidemiological effect of animals on the human transmission of Blastocystis species by molecular methods for in our country. A total of 420 faecal samples were collected from the cattle, sheep, dogs, horses and chickens. Samples were stained with trichrome staining and cultivated by Jones's medium culture method. Blastocystis was detected in 53(12.6%) of 420. The samples were examined by Polymerase Chain Reaction (PCR) to identify nine common human subtypes. Subtypes were not detected in 33(62.3) of the 53 Blastocystis positive samples. Subtypes were detected in 20(37.7%) samples. The detected subtypes were as follows: ST5 in 4(7.5%) sheep, ST6 in 6(11.3%) chickens, ST7 in 11(20.7%) chickens, both ST6-ST7 were detected in one chicken). ST1, ST2, ST3 and ST4 - common subtypes in our country- were not detected in any animal. Sheep and chickens may be the source of human transmission of ST5, ST6 and ST7, the rare subtypes in our country. As a result, humans rather than animals, seem to be the source of the human transmission of Blastocystis sp. in our country.

Anahtar Kelimeler

• Blastocystis sp.
• Molecular epidemiology
• Polymerase Chain Reaction.

Kaynakça

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