Aslan Gönül, Bayram Gül, Otağ Feza, Direkel Sahin, Taylan Özkan Ayşegül, Ceber Kemal, Emekdaş Gürol
Mersin University Faculty of Medicine, Department of Medical Microbiology, Mersin, Turkey.
Mikrobiyol Bul. 2012 Jan;46(1):93-100.
Cryptosporidium is an intracellular protozoon that causes enteritis in human and animals. Contaminated water and food are the major sources for the transmission of oocysts via oral-fecal route. It is reported that the prevalence of cryptosporidiosis is higher in developing countries than developed countries because of inefficient sanitation and disinfection facilities for drinking water. The most frequently detected species is Cryptosporidium parvum leading to high morbidity in healthy subjects and also fatal infections in immunocompromised patients. The acid-fast staining method is widely used in the diagnosis of cryptosporidiosis. Nowadays, Cryptosporidium could easily be detected in water supplies and asymptomatic carriers by molecular techniques to obtain epidemiological data. In this study it was aimed to detect and identify Cryptosporidium oocysts in different water sources in Mersin province, Turkey. A total of 135 water samples (70 taps, 50 wells and 15 sewage) collected from city center (n= 25) and from Tarsus (n= 32), Mezitli (n= 33) and Karaduvar (n= 45) counties between March 2007 and May 2009 were included in the study. Water samples in 10 liter volumes, were filtered by 0.45 µm pore-sized membrane filter vacuum/ pressure pumping technique. Cryptosporidium oocysts in filtrates were detected by modified cold Kinyoun acid-fast stain (MCK) technique and also identified and typed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. MCK yielded three and PCR yielded seven positive results. All the strains were identified as C.parvum by PCR-RFLP method. All of the three MCK-positive samples were also found positive with PCR, however four PCR positive samples were MCK-negative. Thus, the prevalence of C.parvum was estimated as 5.2% (7/135) in our region. Of seven positive samples, one was a sewage water sample collected from the city center, while the remaining (two tap water, two well water and two sewage water samples) belonged to the samples collected from Karaduvar county, interestingly. It was thought that deficient infrastructure and use of well water as drinking water supply in Karaduvar region might be the cause of high rate of Cryptosporidium (6/45; 13.3%). Further studies which will determine the genotypes and investigate the phylogenetic relationship between these Cryptosporidium spp., might aid to the epidemiology of cryptosporidiosis in our region.
隐孢子虫是一种细胞内原生动物，可导致人和动物患肠炎。受污染的水和食物是卵囊经口粪途径传播的主要来源。据报道，由于饮用水卫生和消毒设施不完善，隐孢子虫病在发展中国家的患病率高于发达国家。最常检测到的物种是微小隐孢子虫，它在健康受试者中导致高发病率，在免疫功能低下的患者中也会引发致命感染。抗酸染色法广泛用于隐孢子虫病的诊断。如今，通过分子技术可以很容易地在供水系统和无症状携带者中检测到隐孢子虫，以获取流行病学数据。在本研究中，旨在检测和鉴定土耳其梅尔辛省不同水源中的隐孢子虫卵囊。2007年3月至2009年5月期间，从市中心（n = 25）以及塔尔苏斯（n = 32）、梅齐特利（n = 33）和卡拉杜瓦尔（n = 45）县共采集了135份水样（70份自来水、50份井水和15份污水）纳入研究。10升体积的水样通过0.45 µm孔径的膜过滤器真空/压力抽吸技术进行过滤。通过改良冷金扬抗酸染色（MCK）技术检测滤液中的隐孢子虫卵囊，并通过聚合酶链反应-限制性片段长度多态性（PCR-RFLP）方法进行鉴定和分型。MCK检测出3份阳性结果，PCR检测出7份阳性结果。通过PCR-RFLP方法将所有菌株鉴定为微小隐孢子虫。所有3份MCK阳性样本经PCR检测也呈阳性，然而有4份PCR阳性样本MCK检测为阴性。因此，估计我们地区微小隐孢子虫的患病率为5.2%（7/135）。在7份阳性样本中，1份是从市中心采集的污水样本，而其余的（2份自来水、2份井水和2份污水样本）有趣的是都属于从卡拉杜瓦尔县采集的样本。据认为，卡拉杜瓦尔地区基础设施不足以及使用井水作为饮用水供应可能是隐孢子虫高感染率（6/45；13.3%）的原因。进一步确定这些隐孢子虫物种的基因型并研究其系统发育关系的研究，可能有助于我们地区隐孢子虫病的流行病学研究。
