Dorny P, Praet N, Deckers N, Gabriel S
Department of Animal Health, Institute of Tropical Medicine, B-2000 Antwerp, Belgium.
Vet Parasitol. 2009 Aug 7;163(3):196-206. doi: 10.1016/j.vetpar.2009.05.026. Epub 2009 Jun 6.
Parasitic food-borne diseases are generally underrecognised, however they are becoming more common. Globalization of the food supply, increased international travel, increase of the population of highly susceptible persons, change in culinary habits, but also improved diagnostic tools and communication are some factors associated with the increased diagnosis of food-borne parasitic diseases worldwide. This paper reviews the most important emerging food-borne parasites, with emphasis on transmission routes. In a first part, waterborne parasites transmitted by contaminated food such as Cyclospora cayetanensis, Cryptosporidium and Giardia are discussed. Also human fasciolosis, of which the importance has only been recognised in the last decades, with total numbers of reported cases increasing from less than 3000 to 17 million, is looked at. Furthermore, fasciolopsiosis, an intestinal trematode of humans and pigs belongs to the waterborne parasites as well. A few parasites that may be transmitted through faecal contamination of foods and that have received renewed attention, such as Toxoplasma gondii, or that are (re-)emerging, such as Trypanosoma cruzi and Echinococcus spp., are briefly reviewed. In a second part, meat-borne parasite infections are reviewed. Humans get infected by eating raw or undercooked meat infected with cyst stages of these parasites. Meat inspection is the principal method applied in the control of Taenia spp. and Trichinella spp. However, it is often not very sensitive, frequently not practised, and not done for T. gondii and Sarcocystis spp. Meat of reptiles, amphibians and fish can be infected with a variety of parasites, including trematodes (Opisthorchis spp., Clonorchis sinensis, minute intestinal flukes), cestodes (Diphyllobothrium spp., Spirometra), nematodes (Gnathostoma, spp., anisakine parasites), and pentastomids that can cause zoonotic infections in humans when consumed raw or not properly cooked. Another important zoonotic food-borne trematode is the lungfluke (Paragonimus spp.). Traditionally, these parasitic zoonoses are most common in Asia because of the particular food practices and the importance of aquaculture. However, some of these parasites may emerge in other continents through aquaculture and improved transportation and distribution systems. Because of inadequate systems for routine diagnosis and monitoring or reporting for many of the zoonotic parasites, the incidence of human disease and parasite occurrence in food is underestimated. Of particular concern in industrialised countries are the highly resistant waterborne protozoal infections as well as the increased travel and immigration, which increase the exposure to exotic diseases. The increased demand for animal proteins in developing countries will lead to an intensification of the production systems in which the risk of zoonotic infections needs to be assessed. Overall, there is an urgent need for better monitoring and control of food-borne parasites using new technologies.
食源性寄生虫病通常未得到充分认识，然而它们正变得越来越常见。食品供应的全球化、国际旅行的增加、高度易感人群数量的增多、烹饪习惯的改变，以及诊断工具和交流的改善，都是与全球食源性寄生虫病诊断增加相关的一些因素。本文回顾了最重要的新发食源性寄生虫，重点是传播途径。在第一部分，讨论了通过受污染食物传播的水源性寄生虫，如卡耶塔环孢子虫、隐孢子虫和贾第虫。此外，还探讨了人体肝片吸虫病，其重要性在过去几十年才得到认识，报告病例总数从不到3000例增加到1700万例。此外，姜片虫病，一种人和猪的肠道吸虫，也属于水源性寄生虫。一些可能通过食物粪便污染传播且重新受到关注的寄生虫，如弓形虫，或正在（重新）出现的寄生虫，如克氏锥虫和棘球绦虫属，也进行了简要回顾。在第二部分，回顾了肉源性寄生虫感染。人类通过食用感染了这些寄生虫囊蚴阶段的生肉或未煮熟的肉而感染。肉类检查是控制绦虫属和旋毛虫属的主要方法。然而，它通常不太敏感，经常不实施，而且对弓形虫和肉孢子虫属不进行检查。爬行动物、两栖动物和鱼类的肉可能感染多种寄生虫，包括吸虫（华支睾吸虫属、中华分支睾吸虫、微小肠道吸虫）、绦虫（裂头绦虫属、迭宫绦虫）、线虫（颚口线虫属、异尖线虫寄生虫），以及当生食或未正确烹饪时可导致人类人畜共患感染的舌形虫。另一种重要的人畜共患食源性吸虫是肺吸虫（并殖吸虫属）。传统上，由于特殊的饮食习惯和水产养殖的重要性，这些寄生虫人畜共患病在亚洲最为常见。然而，其中一些寄生虫可能通过水产养殖以及改善的运输和分销系统在其他大陆出现。由于许多人畜共患寄生虫的常规诊断、监测或报告系统不完善，人类疾病的发病率以及食物中寄生虫的发生率被低估。在工业化国家，特别令人担忧的是高度耐药的水源性原生动物感染以及旅行和移民的增加，这增加了接触外来疾病的机会。发展中国家对动物蛋白需求的增加将导致生产系统的强化，其中需要评估人畜共患感染的风险。总体而言，迫切需要利用新技术更好地监测和控制食源性寄生虫。
