Ismail Mousa A M, El-Akkad Dina M H, Rizk Enas M A, El-Askary Hala M, El-Badry Ayman A
Medical Parasitology Department, Kasr Al-Ainy Faculty of Medicine, Cairo University, El-Manial, Cairo, Egypt.
Medical Parasitology Department, Faculty of Medicine, Beni-Suef University, Beni Suef, Egypt.
Parasitol Res. 2016 Nov;115(11):4221-4227. doi: 10.1007/s00436-016-5199-7. Epub 2016 Jul 23.
Giardia lamblia (G. lamblia) is the most worldwide prevailing intestinal parasite, notorious for its broad range of seasonal and age-related prevalence. The potentially lethal nature of giardiasis makes it essential that the seasonality, the groups at risk, and other potential risk factors are identified. The present molecular epidemiological study was designed to determine the genetic diversity of G. lamblia infection, taking into account seasonal peaks, age distribution, and associated symptoms in a cohort of Egyptian diarrheic patients. Stool samples were collected from 1187 diarrheic patients attending outpatient clinics of Cairo University hospitals, of all age groups over a 12-month period. The patients were examined microscopically for fecal G. lamblia cysts, and/or trophozoites, and for copro-DNA detection using nested polymerase chain reaction (nPCR) assays targeting beta giardin gene. PCR-positive samples were characterized molecularly by nPCR restriction fragment length polymorphism (RFLP) to determine Giardia assemblages. The findings revealed circannual prevalence of Giardia, with a seasonal pattern peaking in mid-summer and late winter, with the summer peak preceded by a peak in temperature. Infection was prevailing in 224 (18.9 %) cases, mainly assemblage B (81.2 %) followed by assemblage A (18.8 %). There were statistically significant associations between the detection of Giardia and flatulence, persistent diarrhea, vomiting, and abdominal pain, while gender and intermittent diarrhea showed no association. The pre-school age group was the most vulnerable. This is the first study of molecular characterization of Giardia to determine its circannual prevalence in Egypt, a finding which carries promising potential for the diagnosis, treatment, and elimination of the disease.
蓝氏贾第鞭毛虫（简称贾第虫）是全球最普遍的肠道寄生虫，因其广泛的季节性和与年龄相关的流行率而臭名昭著。贾第虫病潜在的致命性使得确定其季节性、高危人群及其他潜在风险因素至关重要。本分子流行病学研究旨在确定埃及腹泻患者队列中蓝氏贾第鞭毛虫感染的基因多样性，同时考虑季节性高峰、年龄分布及相关症状。在12个月期间，从开罗大学医院门诊的1187例各年龄段腹泻患者中采集粪便样本。对患者进行显微镜检查，以检测粪便中的蓝氏贾第鞭毛虫包囊和/或滋养体，并使用针对β贾第蛋白基因的巢式聚合酶链反应（nPCR）检测粪便DNA。通过nPCR限制性片段长度多态性（RFLP）对PCR阳性样本进行分子特征分析，以确定贾第虫的种群。研究结果显示贾第虫全年流行，呈季节性模式，在仲夏和冬末达到高峰，夏季高峰之前有一个温度高峰。224例（18.9%）患者感染，主要为B种群（81.2%），其次是A种群（18.8%）。贾第虫检测与肠胃胀气、持续性腹泻、呕吐和腹痛之间存在统计学上的显著关联，而性别和间歇性腹泻则无关联。学龄前儿童是最易感染的群体。这是埃及首次对蓝氏贾第鞭毛虫进行分子特征分析以确定其全年流行情况的研究，这一发现对该疾病的诊断、治疗和消除具有广阔的潜在应用前景。
