Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
President's Malaria Initiative, Bureau for Global Health, Office of Infectious Disease, United States Agency for International Development, Washington, DC, United States of America.
PLoS Negl Trop Dis. 2018 Jul 26;12(7):e0006574. doi: 10.1371/journal.pntd.0006574. eCollection 2018 Jul.
Careful monitoring for recrudescence of Wuchereria bancrofti infection is necessary in communities where mass drug administration (MDA) for the elimination of lymphatic filariasis (LF) as a public health problem has been stopped. During the post-MDA period, transmission assessment surveys (TAS) are recommended by the World Health Organization to monitor the presence of the parasite in humans. Molecular xenomonitoring (MX), a method by which parasite infection in the mosquito population is monitored, has also been proposed as a sensitive method to determine whether the parasite is still present in the human population. The aim of this study was to conduct an MX evaluation in two areas of Bangladesh, one previously endemic district that had stopped MDA (Panchagarh), and part of a non-endemic district (Gaibandha) that borders the district where transmission was most recently recorded.
METHODOLOGY/PRINCIPAL FINDINGS: Mosquitoes were systematically collected from 180 trap sites per district and mosquito pools were tested for W. bancrofti using real-time PCR. A total of 23,436 intact mosquitoes, representing 31 species, were collected from the two districts, of which 10,344 (41%) were Culex quinquefasciatus, the vector of W. bancrofti in Bangladesh. All of the 594 pools of Cx. quinquefasciatus tested by real-time PCR were negative for the presence of W. bancrofti DNA.
CONCLUSIONS/SIGNIFICANCE: This study suggested the absence of W. bancrofti in these districts. MX could be a sensitive tool to confirm interruption of LF transmission in areas considered at higher risk of recrudescence, particularly in countries like Bangladesh where entomological and laboratory capacity to perform MX is available.
在停止大规模药物治疗（MDA）以消除淋巴丝虫病（LF）这一公共卫生问题的社区中，有必要仔细监测班氏丝虫感染的复发情况。在 MDA 后期间，世界卫生组织建议进行传播评估调查（TAS），以监测人类寄生虫的存在。分子外来监测（MX）是一种监测蚊群寄生虫感染的方法，也被提议作为一种敏感方法，以确定寄生虫是否仍存在于人群中。本研究旨在对孟加拉国的两个地区进行 MX 评估，一个是以前流行区（Panchagarh），已经停止 MDA，另一个是与最近记录传播的地区接壤的非流行区（Gaibandha）的一部分。
方法/主要发现：每个地区系统地从 180 个陷阱点收集蚊子，并使用实时 PCR 测试蚊子群是否存在班氏丝虫。从这两个地区共收集了 23436 只完整的蚊子，代表 31 个物种，其中 10344 只（41%）为孟加拉国班氏丝虫的传播媒介库蚊。用实时 PCR 测试的所有 594 个库蚊群均为阴性，未检出班氏丝虫 DNA。
结论/意义：本研究表明这些地区不存在班氏丝虫。MX 可能是一种敏感的工具，可以确认在被认为复发风险较高的地区，如孟加拉国，中断 LF 传播，特别是在有能力进行 MX 的国家，如孟加拉国。
