Parasitology Section, Department of Pharmacy Pharmaceutical Technology and Parasitology, School of Pharmacy, University of Valencia, Burjassot-Valencia, Spain.
Mundo Sano Foundation, Buenos Aires, Argentina.
Parasit Vectors. 2021 Oct 1;14(1):510. doi: 10.1186/s13071-021-04968-z.
Intestinal parasites (IPs) are widely distributed worldwide and are one of the major contributors to gastrointestinal disease. Their prevalence is associated with poor access to water, sanitation and hygiene (WASH). The objective of this study was to identify the prevalence of IPs, including soil-transmitted helminths (STH), and their relation to socioeconomic characteristics, as well as a first approach to molecularly characterize the types of Giardia intestinalis, Blastocystis spp. and Entamoeba histolytica present in an indigenous community from Puerto Iguazú, Misiones, Argentina.
A cross-sectional study was conducted in the rural settlement of Fortin Mbororé between January and March 2018. Socioeconomic variables, household characteristics, and stool and blood samples were collected. Standard coprological techniques were used to analyze stool samples, and a complete hemogram was performed on the blood samples. Giardia intestinalis microscopy-positive samples were genetically typed by the β-giardin (bg) gene. Molecular identification of Blastocystis spp. subtypes and E. histolytica were carried out by amplification and sequencing of a partial fragment of the small subunit ribosomal RNA gene (SSU rDNA).
The overall prevalence of IPs was 92.7%, with 72.0% specifically for hookworm. IPs were significantly more prevalent in preschool- and school-age children (P < 0.05). No formal education (P = 0.035), the presence of unimproved floors (P = 0.001) and overcrowding (P = 0.005) were significantly associated with IP infection. Hookworm was associated with anemia (P = 0.019). Molecular characterization revealed the presence of E. histolytica sub-assemblages AII (12.5%), AIII (87.5%) and BIV (100%); one case of sub-assemblage D for G. intestinalis; and the presence of subtypes ST1 (14.8%), ST2 (14.8%) and ST3 (70.4%) of Blastocystis spp.
Protozoans detected in this study are transmitted mainly through water contaminated with fecal matter, evidencing the need to improve the quality of water and sanitation for the inhabitants of Fortín Mbororé. Molecular characterization showed that domestic animals can be implicated in the zoonotic transmission of G. intestinalis and Blastocystis spp. to humans. A hyperendemic area for STH was found, with hookworm prevalence greater than 50%. Therefore, improvements in WASH as well as mass deworming programs need to be implemented in this area to control and decrease the prevalence of IPs in general and STH in particular.
肠道寄生虫（IP）广泛分布于世界各地，是导致胃肠道疾病的主要原因之一。它们的流行与无法获得水、环境卫生和个人卫生（WASH）有关。本研究的目的是确定肠道寄生虫（包括土壤传播的蠕虫（STH））的流行率，及其与社会经济特征的关系，以及首次对阿根廷米西奥内斯省伊瓜苏港的一个土着社区中存在的贾第虫、蓝氏贾第鞭毛虫和溶组织内阿米巴进行分子特征分析。
2018 年 1 月至 3 月期间，在农村 Fortin Mbororé 进行了横断面研究。收集了社会经济变量、家庭特征、粪便和血液样本。使用标准的粪便检查技术分析粪便样本，并对血液样本进行全血细胞计数。显微镜检查发现贾第虫阳性的样本通过β-微管蛋白（bg）基因进行基因分型。通过扩增和测序小亚基核糖体 RNA 基因（SSU rDNA）的部分片段，对蓝氏贾第鞭毛虫亚型和溶组织内阿米巴进行分子鉴定。
肠道寄生虫的总流行率为 92.7%，其中钩虫为 72.0%。肠道寄生虫在学龄前和学龄儿童中更为普遍（P<0.05）。无正规教育（P=0.035）、未改善的地板（P=0.001）和过度拥挤（P=0.005）与肠道寄生虫感染显著相关。钩虫与贫血（P=0.019）有关。分子特征分析显示存在溶组织内阿米巴亚群 AII（12.5%）、AIII（87.5%）和 BIV（100%）；贾第虫的一个亚群 D 案例；和蓝氏贾第鞭毛虫的 ST1（14.8%）、ST2（14.8%）和 ST3（70.4%）亚型。
本研究中检测到的原生动物主要通过受粪便污染的水传播，这表明需要改善 Fortín Mbororé 居民的水和环境卫生质量。分子特征分析表明，家畜可能参与了贾第虫和蓝氏贾第鞭毛虫向人类的动物源性传播。发现了一个土壤传播蠕虫高度流行的地区，钩虫的流行率超过 50%。因此，需要在该地区实施 WASH 改善和大规模驱虫计划，以控制和降低肠道寄生虫和特别是土壤传播蠕虫的流行率。
