Parasitic Infections and Human Migration in Southeast Asia

在为期3年的研究过程中，共进行了6次调查，其中3次针对内杰里·森比兰拘留营的非法移民，3次针对雪兰莪种植园的法律的外籍工人。研究对象共741人，包括308名非法移民、221名法律的外籍劳工和212名本地劳工作为对照。在非法移民中，马来西亚人占主导地位，其次是来自其他亚洲国家的人。法律的外籍劳工多为印尼人，整体而言，非法入境者的寄生虫感染率较高，尤其是致病性原生动物和体外寄生虫，反映他们的生活环境卫生水平较低。这些法律的印度尼西亚工人被发现患有相对较高的无症状疟疾，这可能是他们在印度尼西亚进行家访时感染的。当地工人根据其种族表现出不同的寄生虫感染特征。原籍国似乎对寄生虫感染的状况有影响。我们试图确定非地方性感染，但在外国人中没有发现任何阳性病例。然而，许多感染可能是由来自原籍国的法律的和非法的移徙工人带来的。因此，感染这些病毒的移民肯定会在维持马来西亚一定程度的感染方面发挥重要作用。法律的移民在东道国享有行动自由，这为新疾病的传播提供了充分的机会。对于输入性寄生虫病，入境时的健康检查对防止传染病传入国内具有重要作用，但对非法入境者来说是不可能的。

In the course of study for 3 years, a total of 6 surveys, 3 for illegal immigrants in a detention camp in Negeri Sembilan and 3 for legal foreign workers in a plantation estate in Selangor, was carried out. A total of 741 study subjects consisted of 308 illegal immigrants, 221 legal foreign workers and 212 local workers as control. Indonesians were dominated among the illegal immigrants followed by those from other Asian countries. Most of the legal foreign workers were Indonesian.As a whole, prevalence of parasitic infections was higher in illegal immigrants, particularly for pathogenic protozoa and ectoparasites, reflecting lower hygienic standard of their living condition. The legal Indonesian workers were found to have a relatively high prevalence of asymptomatic malaria, which may have been acquired when they went on a home visit in Indonesia. The local workers showed different features of parasitic infections according to their ethnicity. Country of origin appeared to have an influence on the status of parasitic infections.Our attempts to identify non-endemic infections did not detect any positive cases among the foreigners. However, many infections could have been brought by migrant workers, both legal and illegal, from their country of origin. Thus the migrants with these infections certainly will play an important role in sustaining the infections at a certain level in Malaysia. The legal migrants enjoy the freedom of movement within the host country, and this provides ample opportunities for the spread of new diseases. For the imported parasitoses, health check at entrance of immigrants could have an important role to prevent spreading out the infections into the country, although it is impossible for the illegal immigrants.