农村地区学龄前和学龄儿童的肠道血吸虫病：消除倡议。

Intestinal schistosomiasis among preschool and school-aged children in a rural setting near Alexandria: initiative for elimination.

机构信息

Department of Parasitology, Medical Research Institute, University of Alexandria, Alexandria, Egypt.

Department of Microbiology, Medical Research Institute, University of Alexandria, Alexandria, Egypt.

出版信息

Trop Med Int Health. 2021 Jun;26(6):632-639. doi: 10.1111/tmi.13562. Epub 2021 Mar 31.

DOI:10.1111/tmi.13562

PMID:33576107

Abstract

OBJECTIVE

To assess the status of intestinal schistosomiasis among preschool-aged (PSAC) and school-aged children (SAC) and to compare the efficacy of praziquantel (PZQ) in both groups.

METHODS

The study was conducted on 400 children; 103 PSAC and 297 SAC. Diagnosis of Schistosoma mansoni was based on triplicate Kato-Katz thick smears from a single stool sample. To identify the missed cases by Kato-Katz, 120 randomly selected negative cases (38 PSAC and 82 SAC) were screened by real-time PCR. All S. mansoni-positive cases by Kato-Katz were treated by crushed PZQ tablets. Four weeks after treatment, the cure rate was assessed by Kato-Katz smears and real-time PCR.

RESULTS

The prevalence of S. mansoni with Kato-Katz was 7.8% among PSAC and 7.4% among SAC. Most of children (63.3%) had light-intensity infection. The cure rate was 100% among PSAC by both techniques, and 91%, and 77.2% among SAC by Kato-Katz and real-time PCR, respectively. In the 120 stool samples screened by real-time PCR, S. mansoni prevalence was 25%; 15.8% and 29.3% were among PSAC and SAC respectively. Treated cases showed a lower range of Ct values than untreated cases. Two melting temperature ranges (Tm = 83-87°C and 89-93°C) were recognised among uncured cases which may point to S. mansoni genetic variability.

CONCLUSION

Continuous monitoring and inclusion of PSAC in schistosomiasis control programmes are crucial. Real-time PCR and other molecular tools are recommended for evaluation of the true prevalence, assessment of cure and further studies on genetic diversity.

摘要

目的

评估学龄前儿童（PSAC）和学龄儿童（SAC）的肠道血吸虫病感染状况，并比较吡喹酮（PZQ）在两组中的疗效。

方法

本研究纳入了 400 名儿童，其中 103 名为 PSAC，297 名为 SAC。曼氏血吸虫病的诊断基于单个粪便样本的三重 Kato-Katz 厚涂片。为了发现 Kato-Katz 漏检的病例，对 120 例随机选择的阴性病例（38 例 PSAC 和 82 例 SAC）进行了实时 PCR 筛查。所有 Kato-Katz 阳性的曼氏血吸虫病患者均采用粉碎的 PZQ 片剂进行治疗。治疗 4 周后，采用 Kato-Katz 涂片和实时 PCR 评估治愈率。

结果

PSAC 中曼氏血吸虫病的 Kato-Katz 流行率为 7.8%，SAC 中为 7.4%。大多数儿童（63.3%）感染程度较轻。两种技术均显示 PSAC 的治愈率为 100%，而 SAC 的治愈率分别为 Kato-Katz 法 91%和实时 PCR 法 77.2%。在实时 PCR 筛查的 120 份粪便样本中，曼氏血吸虫病的流行率为 25%；PSAC 和 SAC 中的感染率分别为 15.8%和 29.3%。治疗组的 Ct 值范围低于未治疗组。未治愈组中发现了两个解链温度范围（Tm=83-87°C 和 89-93°C），这可能表明曼氏血吸虫的遗传变异。