Sahimin Norhidayu, Lim Yvonne Ai Lian, Douadi Benacer, Mohd Khalid Mohd Khairul Nizam, Wilson John-James, Behnke Jerzy M, Mohd Zain Siti Nursheena
Institute of Biological Science, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.
Acta Trop. 2017 Sep;173:109-115. doi: 10.1016/j.actatropica.2017.06.011. Epub 2017 Jun 10.
Ongoing urbanisation of the working population as well as cross-border migration of workers particularly into large cities has contributed to the development and growth of urban slums. These deprived areas are conducive for the transmission of intestinal pathogens including hookworm. The aim of this study was to determine both the prevalence and species identity of hookworm infections among the migrant worker community in Malaysia. A total of 388 faecal samples were collected from migrant workers between September 2014 and August 2015, representing workers from five employment sectors: construction, manufacturing, agriculture and plantations, food services and domestic services. Faecal samples were examined by microscopy and positive samples were subjected to molecular analysis. A total of 51 samples (13.1%) were positive by microscopy for hookworm infections. A two-step PCR based method amplifying a fragment of the 28S rRNA-ITS2 region was used to identify infections by Necator americanus and Ancylostoma spp. PCR products positive for Ancylostoma spp. were sequenced bidirectionally, and sequences analysed through BLAST and phylogenetic analysis. Samples containing Ancylostoma duodenale were further characterized by amplification and sequencing a fragment of cytochrome c oxidase subunit 1 (cox1) gene. PCR amplicons were successfully obtained from 42 (82.4%) of 51 samples, with 81.0% (34 of 42) identified as Necator americanus, 16.7% (7 of 42) as Ancylostoma spp. and 2.4% (1 of 42) as mixed infections of both species. All eight Ancylostoma spp. were confirmed to be Ancylostoma duodenale and this is the first time A. duodenale was reported in Malaysia. Samples containing A. duodenale from Nepalese and Indonesian workers shared high-similarity and were distinct compared to sequences from other countries. This study highlights the prevalence of hookworm infections among migrant workers living in Malaysia. Our findings underscore the necessity of screening migrant workers for hookworm infections, particularly those working in food-related services and industries.
在职人口的持续城市化以及工人的跨境迁移，尤其是向大城市的迁移，导致了城市贫民窟的发展和扩大。这些贫困地区有利于包括钩虫在内的肠道病原体的传播。本研究的目的是确定马来西亚农民工群体中钩虫感染的患病率和种类。2014年9月至2015年8月期间，共收集了388份农民工粪便样本，这些样本代表了五个就业部门的工人：建筑、制造、农业和种植园、食品服务和家政服务。通过显微镜检查粪便样本，对阳性样本进行分子分析。共有51份样本（13.1%）通过显微镜检查发现钩虫感染呈阳性。采用两步PCR法扩增28S rRNA-ITS2区域的片段，以鉴定美洲板口线虫和钩口线虫属的感染。对钩口线虫属PCR产物进行双向测序，并通过BLAST和系统发育分析对序列进行分析。通过扩增和测序细胞色素c氧化酶亚基1（cox1）基因的片段，对含有十二指肠钩口线虫的样本进行进一步鉴定。从51份样本中的42份（82.4%）成功获得了PCR扩增产物，其中81.0%（42份中的34份）被鉴定为美洲板口线虫，16.7%（42份中的7份）为钩口线虫属，2.4%（42份中的1份）为两种物种的混合感染。所有8份钩口线虫属样本均被确认为十二指肠钩口线虫，这是马来西亚首次报告十二指肠钩口线虫。来自尼泊尔和印度尼西亚工人的含有十二指肠钩口线虫的样本具有高度相似性，与其他国家的序列不同。本研究突出了生活在马来西亚的农民工中钩虫感染的患病率。我们的研究结果强调了对农民工进行钩虫感染筛查的必要性，特别是那些从事与食品相关服务和行业的农民工。
