Semi-Automated Microfluidic Device Combined with a MiniPCR-Duplex Lateral Flow Dipstick for Screening and Visual Species Identification of Lymphatic Filariae.

Achinya Phuakrod,Pattaraluck Pattamang,Witsaroot Sripumkhai,Sirichit Wongkamchai,Navapon Kusuwan

doi:10.3390/mi13020336

Abstract

Lymphatic filariasis (LF) is a leading cause of permanent disability worldwide that has been listed as a neglected tropical disease by the World Health Organization. Significant progress made by the Global Program to Eliminate Lymphatic Filariasis (GPELF) has led to a substantial decline in the population of the worm that causes LF infection. Diagnostic assays capable of detecting low levels of parasite presence are needed to diagnose LF. There is also a need for new tools that can be used in areas where multiple filarial species are coendemic and for mass screening or for use in a point-of-care setting. In the present study, we applied our previously developed semi-automated microfluidic device in combination with our recently developed mini polymerase chain reaction (miniPCR) with a duplex lateral flow dipstick (DLFD) (miniPCR-DLFD) for rapid mass screening and visual species identification of lymphatic filariae in human blood. The study samples comprised 20 Brugia malayi microfilariae (mf) positive human blood samples, 14 Wuchereria bancrofti mf positive human blood samples and 100 mf negative human blood samples. Microfilariae detection and visual species identification was performed using the microfluidic device. To identify the species of the mf trapped in the microfluidic chips, DNA of the trapped mf was extracted for miniPCR amplification of W. bancrofti and B. malayi DNA followed by DLFD. Thick blood smear staining for microfilariae detection was used as the gold standard technique. Microfilariae screening and visual species identification using our microfluidic device plus miniPCR-DLFD platform yielded results concordant with those of the gold standard thick blood smear technique. The microfluidic device, the miniPCR and the DLFD are all portable and do not require additional equipment. Use of this screening and visual species identification platform will facilitate reliable, cost-effective, and rapid surveillance for the presence of LF infection in resource-poor settings.

Highlights

Licensee MDPI, Basel, Switzerland.Lymphatic filariasis (LF) is a mosquito-borne, globally distributed tropical disease that can cause permanent disability and is a significant threat to public health worldwide
The 100 mf negative blood samples were confirmed negative by no mf detection by either thick blood smear staining or by the microfluidic device
Species identification of the trapped mf was performed by mini polymerase chain reaction (miniPCR) thermocycler followed by duplex lateral flow dipstick (DLFD)

Summary

Introduction

Licensee MDPI, Basel, Switzerland.Lymphatic filariasis (LF) is a mosquito-borne, globally distributed tropical disease that can cause permanent disability and is a significant threat to public health worldwide. A variety of assays are available for diagnosing and/or monitoring LF infection, including thick blood smear staining for microfilaria detection, antigen and antibody detection testing and parasite nucleic acid detection testing [1]. The microfilaria detection using the thick blood smear staining technique, it is easy and cheap to perform, cannot be published maps and institutional affil-. Micromachines 2022, 13, 336 accomplished within one day because the drying step of the smear slide requires 12–48 h, according to the World Health Organization’s procedure [2], it is not suitable to be a point of care testing. A high number of slides to be examined under the microscope may lead to incorrect diagnoses when fatigue occurs [3]

Methods

Results

Discussion

Conclusion