Schneider Renate, Auer Herbert
Department of Medical Parasitology, Institute of Specific Prophylaxis and Tropical Medicine, Center of Pathophysiology, Infectiology and Immunology, Medical University Vienna, Kinderspitalgasse 15, A-1095, Vienna, Austria.
Parasitol Res. 2016 Mar;115(3):1213-9. doi: 10.1007/s00436-015-4857-5. Epub 2015 Dec 5.
The pig roundworm, Ascaris suum, is commonly found in domestic pigs all over the world. The transmission to humans takes place by ingestion of infective A. suum eggs present in soil because pig manure is widely used as fertilizer. The possible role of A. suum in the human visceral larva migrans (VLM) syndrome has been discussed controversially during past decades, even though various case reports, particularly from Japan document pulmonal, hepatic and even cerebral symptoms caused by migrating A. suum larvae after ingestion of infected row meat (liver) or contaminated vegetables. We examined 4481 sera by A. suum immunoblot (As-IB) and 5301 sera by Toxocara-ELISA from patients with symptoms associated with the VLM syndrome during three consecutive years (2012-2014). The incidence of A. suum-specific antibodies was 13.2 %, the incidence of T. canis specific antibodies 12.9 % and from a part of the As-IB positive sera (n = 417) additional Toxocara serology was performed to demonstrate the specificity of our tests. Only 56 out of the 417 (13.4 %) sera showed antibodies to both helminth species demonstrating that double infections exist. Interestingly the age distribution of the patients showed that 2.8 % of the Ascaris-positive patients were younger than 21 years, while in the Toxocara-positive group 13.4 % were <21 years. These results are in accordance with a Dutch study suspecting different ways of transmission as cause for this interesting age distribution. Due to the fact that large amounts of untreated pig manure are used as fertilizer and that the expulsion of adult A. suum worms causing intestinal ascariosis is extremely rare in Central European countries, the zoonotic potential of A. suum is considerably underestimated. We suggest that the performance of reliable immunoserological tests, in all industrialized countries where pigs are raised and their manure is used as fertilizer, could help to assess the actual potential of A. suum as causative agent of the VLM syndrome in humans.
猪蛔虫（Ascaris suum）在世界各地的家猪中普遍存在。由于猪粪被广泛用作肥料，人类通过摄入土壤中存在的感染性猪蛔虫卵而被感染。在过去几十年中，猪蛔虫在人类内脏幼虫移行症（VLM）综合征中的可能作用一直存在争议，尽管有各种病例报告，特别是来自日本的报告记录了摄入受感染的生肉（肝脏）或受污染蔬菜后，猪蛔虫幼虫移行引起的肺部、肝脏甚至脑部症状。我们在连续三年（2012 - 2014年）对4481份血清进行了猪蛔虫免疫印迹（As - IB）检测，对5301份血清进行了犬弓首蛔虫酶联免疫吸附测定（Toxocara - ELISA）检测，这些血清来自有VLM综合征相关症状的患者。猪蛔虫特异性抗体的发生率为13.2%，犬弓首蛔虫特异性抗体的发生率为12.9%，并且对部分As - IB阳性血清（n = 417）进行了额外的弓首蛔虫血清学检测以证明我们检测的特异性。417份血清中只有56份（13.4%）显示对两种蠕虫均有抗体，表明存在双重感染。有趣的是，患者的年龄分布显示，2.8%的蛔虫阳性患者年龄小于21岁，而在犬弓首蛔虫阳性组中，13.4%的患者年龄小于21岁。这些结果与一项荷兰研究一致，该研究怀疑不同的传播方式是造成这种有趣年龄分布的原因。由于在中欧国家大量未经处理的猪粪被用作肥料，并且导致肠道蛔虫病的成年猪蛔虫排出极为罕见，猪蛔虫的人畜共患病潜力被大大低估。我们建议，在所有养猪且猪粪用作肥料的工业化国家，开展可靠的免疫血清学检测，有助于评估猪蛔虫作为人类VLM综合征病原体的实际潜力。
