Publication: İç Anadolu Bölgesinde Francisella tularensis alt tür halorctica’ya Bağlı Su Kaynaklı Bir Tularemi Salgını
Abstract
Bu çalışmada, 18 Kasım 2009-24 Aralık 2009 tarihleri arasında Çankırı ili, Çerkeş ilçesi, Kadıözü köyünde meydana gelen su kaynaklı tularemi salgını araştırılmıştır. 18 Kasım 2009 tarihinde aynı köyden gelen iki hastaya orofarengeal tularemi tanısı konulmasının ardından, o bölgede hastaların klinik özelliklerini ve risk faktörlerini belirlemek amacıyla aktif sürveyans çalışması yapılmıştır. Saha taramasında hastalar muayene edilmiş, olgulardan ve salgının kaynağı olabileceği düşülen su kaynaklarından örnekler alınmıştır. Orofarengeal, glandüler ve pnömonik formda olan olgulardan alınan boğaz sürüntüsü, lenf nodu aspiratları ile salgın bölgesindeki su kaynaklarından alınan örneklerde, kültür ve polimeraz zincir reaksiyonu (PCR) yöntemleriyle Francisella tularensis varlığı araştırılmıştır. Tüm köy halkından alınan serum örneklerinde mikroaglütinasyon testi (MAT) ile F.tularensis antikorları taranmıştır. Klinik ve laboratuvar sonuçlarına dayanarak, 11’i orofarengeal, üçü glandüler ve biri pnömonik formda olmak üzere toplam 15 hastaya tularemi tanısı konulmuştur. Hastaların yaşları 6-75 yıl arasında değişmekte olup (ortalama yaş: 52.5 yıl), 31 (%54.7)’i kadındır. Tularemi olgularının MAT titrelerinin 1/160-1/5120 arasında değiştiği gözlenmiştir. Beş hastadan alınan klinik örneklerin ikisinde (bir boğaz sürüntüsü ve bir lenf nodu aspiratı olmak üzere) etken üretilmiştir. PCR ile bir boğaz sürüntüsü ve dört lenf nodu aspiratında F.tularensis DNA’sı gösterilmiştir. Köylülerin ortak kullandığı kaynak suyu örneğinde PCR ile F.tularensis saptanmıştır. İki olgudan alınan lenf nodu aspiratının birisi direkt floresan antikor yöntemiyle pozitif olarak bulunmuştur. Etken, konvansiyonel ve moleküler yöntemlerle F.tularensis alt tür holarctica olarak tanımlanmıştır. Hastalar aminoglikozid (streptomisin, gentamisin ve amikasin) ve kinolon (siprofloksasin veya levofloksasin) ile tedavi edilmiş, ancak beş olguda tedavide gecikmeye bağlı olarak tedavi başarısızlığı saptanmıştır. Tularemi olgularının ve kontrollerinin özellikleri ve risk faktörleri karşılaştırıldığında; yaş ve evde kemirgen atığı ile temas istatistiksel olarak anlamlı bulunmuştur (p= 0.001 ve p= 0.002). Kaynak sularının toplandığı deponun temizlenmesi ve suların klorlanması ile salgın kontrol altına alınmıştır. Tularemi, ülkemizde endemik olmayan bölgelere yayılmakta ve halk sağlığı açısından önemli bir tehdit oluşturmaktadır.
In this study, we investigated a waterborne tularemia outbreak occured in Kadiozu, a village of Cerkes county of Cankiri province (located in North-west part of central Anatolia, Turkey) between 18 November 2009-24 December 2009. Active surveillance was conducted to determine clinical characteristics and risk factors of cases after two patients from the same village had been diagnosed as oropharyngeal tularemia. All villagers were examined, and clinical specimens from cases and water samples which may be the source of outbreak in the field investigations were taken. Cases were in the form of oropharyngeal, glandular and pneumonic. Polymerase chain reaction (PCR) and cultures were conducted from lymph node aspirates, throat swabs taken from cases and samples from water sources of epidemic zone. All serum samples taken from the villagers were screened for F.tularensis antibodies with microagglutination test (MAT). Oropharyngeal tularemia was diagnosed in 11 patients, glandular form in 3 patients and pneumonic form in one patient according to clinical and laboratory results. Age of the patients ranged between 6-75 years old (mean age: 52.5 years) and thirty one of them (54.7%) were female. MAT titers ranged between 1/160 and 1/5120 in cases of tularemia. Causative agent was grown in the cultures of two patients (including a throat swab and a lymph node aspirate). F.tularensis DNA was shown by PCR in a throat swab and four lymph node aspirates. F.tularensis was also detected by PCR in the water sample obtained from one of the spring water commonly used by villagers. Only one of the lymph node samples obtained from two different patients, was positive by direct fluorescent antibody method. Causative agent was defined as F.tularensis subsp. holarctica by conventional and also molecular methods. Patients were treated with aminoglycoside (streptomycin, gentamicin, amikacin) or quinolone (ciprofloxacin, levofloxacin) antibiotics. Treatment failure was observed in five patients, due to the delay in initiating treatment. Comparison of characteristics and risk factors for tularemia cases versus controls yielded age and contact with rodent excreta at home as potential risk factors (p= 0.001 and 0.002, respectively). The epidemic was controlled after cleaning the tank collecting spring water and chlorination of the water. Tularemia which is an emerging disease in Turkey is spreading to non-endemic regions and represent a significant threat for public health.
In this study, we investigated a waterborne tularemia outbreak occured in Kadiozu, a village of Cerkes county of Cankiri province (located in North-west part of central Anatolia, Turkey) between 18 November 2009-24 December 2009. Active surveillance was conducted to determine clinical characteristics and risk factors of cases after two patients from the same village had been diagnosed as oropharyngeal tularemia. All villagers were examined, and clinical specimens from cases and water samples which may be the source of outbreak in the field investigations were taken. Cases were in the form of oropharyngeal, glandular and pneumonic. Polymerase chain reaction (PCR) and cultures were conducted from lymph node aspirates, throat swabs taken from cases and samples from water sources of epidemic zone. All serum samples taken from the villagers were screened for F.tularensis antibodies with microagglutination test (MAT). Oropharyngeal tularemia was diagnosed in 11 patients, glandular form in 3 patients and pneumonic form in one patient according to clinical and laboratory results. Age of the patients ranged between 6-75 years old (mean age: 52.5 years) and thirty one of them (54.7%) were female. MAT titers ranged between 1/160 and 1/5120 in cases of tularemia. Causative agent was grown in the cultures of two patients (including a throat swab and a lymph node aspirate). F.tularensis DNA was shown by PCR in a throat swab and four lymph node aspirates. F.tularensis was also detected by PCR in the water sample obtained from one of the spring water commonly used by villagers. Only one of the lymph node samples obtained from two different patients, was positive by direct fluorescent antibody method. Causative agent was defined as F.tularensis subsp. holarctica by conventional and also molecular methods. Patients were treated with aminoglycoside (streptomycin, gentamicin, amikacin) or quinolone (ciprofloxacin, levofloxacin) antibiotics. Treatment failure was observed in five patients, due to the delay in initiating treatment. Comparison of characteristics and risk factors for tularemia cases versus controls yielded age and contact with rodent excreta at home as potential risk factors (p= 0.001 and 0.002, respectively). The epidemic was controlled after cleaning the tank collecting spring water and chlorination of the water. Tularemia which is an emerging disease in Turkey is spreading to non-endemic regions and represent a significant threat for public health.