Department of Hygiene and Zoonoses, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt.
Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, 30329, USA.
Parasit Vectors. 2018 Jul 11;11(1):403. doi: 10.1186/s13071-018-2981-7.
The transmission of Cryptosporidium spp. and Giardia duodenalis into humans varies according to species/genotypes of the pathogens. Although infections with both parasites are recorded in Egypt, few data are available on the distribution of Cryptosporidium species and G. duodenalis genotypes. The present study assessed the occurrence and genetic diversity of Cryptosporidium spp. and G. duodenalis in Egyptian children.
In the present study, 585 fecal specimens were collected from children eight years old and younger in three provinces (El-Dakahlia, El-Gharbia and Damietta) during March 2015 to April 2016. PCR-RFLP analysis of the small subunit rRNA gene and sequence analysis of the 60 kDa glycoprotein gene were used to detect and subtype Cryptosporidium spp., respectively, whereas PCR and sequence analyses of the triose phosphate isomerase, glutamate dehydrogenase and β-giardin genes were used to detect and genotype Giardia duodenalis.
The overall infection rates of Cryptosporidium spp. and G. duodenalis were 1.4% and 11.3%, respectively. The Cryptosporidium species identified included C. hominis and C. parvum, each with three subtype families. The C. hominis subtypes were IbA6G3 (n = 2), IdA17 (n = 1), IdA24 (n = 1) and IfA14G1R5 (n = 1), while C. parvum subtypes were IIdA20G1 (n = 1), IIaA15G2R1 (n = 1), and IIcA5G3a (n = 1). The G. duodenalis identified included both assemblages A (n = 31) and B (n = 34). All G. duodenalis assemblage A belonged to the anthroponotic sub-assemblage AII, while a high genetic heterogeneity was seen within assemblage B.
Data from this study are useful in our understanding of the genetic diversity of Cryptosporidium spp. and G. duodenalis in Egypt and the potential importance of anthroponotic transmission in the epidemiology of both pathogens.
隐孢子虫和十二指肠贾第鞭毛虫的传播途径因病原体的种类/基因型而异。虽然埃及有记录表明存在这两种寄生虫感染，但有关隐孢子虫种类和十二指肠贾第鞭毛虫基因型的分布数据却很少。本研究评估了埃及儿童中隐孢子虫和十二指肠贾第鞭毛虫的感染情况和遗传多样性。
本研究于 2015 年 3 月至 2016 年 4 月在埃及三个省份（代尔盖莱卜省、盖勒尤卜省和达米埃塔省）采集了 585 份 8 岁及以下儿童的粪便样本。采用 PCR-RFLP 分析和 60 kDa 糖蛋白基因序列分析分别检测和亚型鉴定隐孢子虫，而采用 PCR 和序列分析三磷酸甘油醛异构酶、谷氨酸脱氢酶和β-微管蛋白基因分别检测和基因型鉴定十二指肠贾第鞭毛虫。
隐孢子虫和十二指肠贾第鞭毛虫的总感染率分别为 1.4%和 11.3%。鉴定出的隐孢子虫种类包括人隐孢子虫和微小隐孢子虫，各有三种亚型家族。人隐孢子虫的亚型包括 IbA6G3（n = 2）、IdA17（n = 1）、IdA24（n = 1）和 IfA14G1R5（n = 1），而微小隐孢子虫的亚型包括 IIdA20G1（n = 1）、IIaA15G2R1（n = 1）和 IIcA5G3a（n = 1）。鉴定出的十二指肠贾第鞭毛虫包括 A 群（n = 31）和 B 群（n = 34）。所有的十二指肠贾第鞭毛虫 A 群均属于人际传播的 AII 亚群，而 B 群内存在高度的遗传异质性。
本研究的数据有助于我们了解埃及隐孢子虫和十二指肠贾第鞭毛虫的遗传多样性，以及这两种病原体在流行病学中人际传播的潜在重要性。
