Horiuchi Saori, Paller Vachel Gay V, Uga Shoji
Department of Parasitology, Faculty of Health Sciences, Kobe University Graduate, School of Health Sciences, Kobe, Japan.
Trop Biomed. 2013 Sep;30(3):495-503.
Infectious diseases caused by soil-transmitted helminths (STHs) are important diseases of humans, which affect about one third of the world's population. Examination of soil can be used to estimate the risk of STH infection in humans. We carried out this survey to clarify the current status of soil contamination by parasite eggs and to assess the risk of STH infection. During survey periods, we examined soil, faeces, and the lifestyle of residents. Six genera and eight species of parasite eggs including Ascaris lumbricoides, Toxocara cati, Toxocara canis, and Trichuris trichiura were recovered from 85 out of 120 soil samples (71%). Contamination of soil by parasite eggs had spread widely throughout the village, and 50% of eggs recovered had already developed into fertilized eggs. It is remarkable that Ascaris eggs were recovered from inside the houses. Prevalence of STH in school children was 63%. This may indicate that school or preschool children cause soil contamination. Some of the eggs recovered were not only from humans but also from dogs and cats. From the results obtained, the need for health education with regards to zoonoses was revealed because 77% of fertilized Toxocara spp. eggs were detected. We conclude that the risk of STH infection in residents was extremely high, because the soil in this village was highly contaminated by infective parasite eggs.
土源性蠕虫（STH）引起的传染病是人类的重要疾病，影响着世界约三分之一的人口。对土壤进行检测可用于估计人类感染STH的风险。我们开展此项调查以明确寄生虫卵对土壤的污染现状，并评估STH感染风险。在调查期间，我们检测了土壤、粪便以及居民的生活方式。从120份土壤样本中的85份（71%）检出了包括蛔虫、猫弓首线虫、犬弓首线虫和鞭虫在内的6个属8种寄生虫卵。寄生虫卵对土壤的污染已在整个村庄广泛传播，且检出的虫卵中有50%已发育为受精卵。值得注意的是，在房屋内部也检出了蛔虫卵。学龄儿童的STH感染率为63%。这可能表明中小学或学龄前儿童造成了土壤污染。检出的部分虫卵不仅来自人类，还来自狗和猫。根据所得结果，鉴于77%的弓首线虫属受精卵被检出，表明有必要开展关于人畜共患病的健康教育。我们得出结论，由于该村庄的土壤被感染性寄生虫卵高度污染，居民感染STH的风险极高。
