Bureau of Microbial Hazards, Food Directorate, Health Canada, 251 Sir Frederick Banting Driveway, Ottawa, Ontario K1A 0K9, Canada.
Res Vet Sci. 2021 Mar;135:283-289. doi: 10.1016/j.rvsc.2020.09.034. Epub 2020 Sep 30.
Giardia duodenalis is a protozoan parasite infecting the upper intestinal tract of humans, as well as domestic and wild animals worldwide. Transmission of giardiasis occurs through the faecal-oral route, and may be either direct (i.e., person-to-person, animal-to-animal or zoonotic) or indirect (i.e., waterborne or foodborne). While asymptomatic infections are common in both humans and animals, a wide range of enteric symptoms have been reported, along with extra-intestinal and post-infectious complications. A definitive diagnosis of giardiasis is generally made by detection of cysts in stool specimens through microscopical examination of wet mounts, or through the use of permanent or fluorescent antibody stains. More recently, molecular methods have become popular for diagnosis and for testing environmental samples. Symptomatic giardiasis is often treated to reduce the duration of symptoms, to prevent complications, and to minimize transmission of the parasite to other hosts. Direct faecal-oral transmission of giardiasis can be largely controlled thorough improved hygiene and sanitation. In the case of waterborne transmission, a multiple barrier approach, including limiting access of people and animals to watersheds and reservoirs, and treatment using flocculation, filtration and disinfection, is necessary to minimize the risk. Since foodborne transmission is often associated with the consumption of fresh produce, a number of control measures can be taken during pre- and post-harvest, as well as at the food handler/consumer level to minimize the risk of contamination, or for removing or inactivating parasites. Good husbandry and farm management practices are important in controlling the spread of giardiasis in livestock and companion animals.
十二指肠贾第鞭毛虫是一种寄生在人类上消化道以及全球家养和野生动物中的原生动物寄生虫。贾第虫病通过粪-口途径传播，可直接（即人与人之间、动物与动物之间或人畜共患）或间接（即水传播或食物传播）传播。虽然人类和动物中无症状感染很常见，但已报告了广泛的肠道症状，以及肠外和感染后并发症。贾第虫病的明确诊断通常通过显微镜检查湿片粪便标本中囊的检测，或通过使用永久或荧光抗体染色来进行。最近，分子方法已成为诊断和检测环境样本的流行方法。有症状的贾第虫病通常通过治疗来缩短症状持续时间，预防并发症，并最大程度地减少寄生虫向其他宿主的传播。通过改善卫生和环境卫生，可以在很大程度上控制直接粪-口传播的贾第虫病。在水传播的情况下，需要采取多种屏障方法，包括限制人和动物进入集水区和水库，并使用絮凝、过滤和消毒进行处理，以最大限度地降低风险。由于食源性传播通常与食用新鲜农产品有关，因此可以在收获前后以及在食品处理者/消费者层面采取一些控制措施，以最大程度地降低污染风险，或去除或灭活寄生虫。良好的饲养和农场管理实践对于控制家畜和伴侣动物中贾第虫病的传播非常重要。
