Nav: Home

Fast test can monitor drug resistance in hookworms

December 08, 2016

More than 2 billion people around the world are infected with intestinal helminths, parasitic worms that can cause disease, complicate pregnancies, and stunt the growth of children. A number of drugs are currently used to treat hookworms, one of the most common helminths to infect humans, but many worry that prolonged use of the drugs could lead to drug-resistant worms. Now, researchers have described, in PLOS Neglected Tropical Diseases, a rapid test that can monitor hookworm DNA for drug resistance mutations.

The hookworm Necator americanus, which causes 85% of all hookworm infections in the world, is treated with the benzimidazole (BZ) drugs, albendazole (ABZ) and mebendazole (MBZ). But overuse of the same drugs to treat livestock infected with worms previously led to the emergence of drug resistant strains. The current techniques available to test for this drug resistance among helminths that infect humans, such as Necator americanus, rely on DNA sequencing and are time-consuming and difficult to carry out in the field.

In the new work, Roger Prichard, of McGill University, Canada, and colleagues adapted an existing assay, called the Smart amplification (SmartAmp) method, to test hookworms for three known drug resistance mutations. Rather than sequence the whole hookworm genome, the approach measures the occurrence of short nucleotide polymorphisms (SNPs) that indicate these mutations. The researchers tested the method on isolated hookworm eggs, field samples containing larvae, and human fecal samples that were both positive and negative for hookworm and compared the results with those found using the standard, slower, PCR-based method.

The new SmartAmp assay, they showed, has high specificity and can detect hookworms carrying the drug-resistance markers in as little as 1% of a sample, taking only about 60 minutes to provide results. Moreover, the results obtained matched with those the researchers got with the PCR approach. Additional methods to better isolate helminth eggs and extract the DNA may improve the assay even more, they speculate.

"The development of sensitive and practical methods for early detection of resistance using molecular diagnostic tools that could be adapted to the field is urgently needed to sustain the benefits of helminth control programs," the researchers say. "These results indicate that our SNP genotyping assays are rapid, simple, very sensitive, and highly specific."
-end-
Please contact plosntds@plos.org if you would like more information about our content and specific topics of interest.

All works published in PLOS Neglected Tropical Diseases are open access, which means that everything is immediately and freely available. Use this URL in your coverage to provide readers access to the paper upon publication:

http://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0005113 (Link goes live upon article publication)

Citation: Rashwan N, Bourguinat C, Keller K, Gunawardena NK, de Silva N, Prichard R (2016) Isothermal Diagnostic Assays for Monitoring Single Nucleotide Polymorphisms in Necator americanus Associated with Benzimidazole Drug Resistance. PLoS Negl Trop Dis 10(12): e0005113. doi:10.1371/journal.pntd.0005113

Funding: This study was funded by the Natural Sciences and Engineering Research Council of Canada (NSERC) (Grant No. RGPIN/2777-2012), and the Fonds de recherche du Québec - Nature et technologies (FRQNT) through the Centre for Host-Parasite Interactions, Québec, Canada. NR received a fellowship from FRQNT. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interests: The authors have declared that no competing interests exist.

PLOS

Related Dna Articles:

Zigzag DNA
How the cell organizes DNA into tightly packed chromosomes. Nature publication by Delft University of Technology and EMBL Heidelberg.
Scientists now know what DNA's chaperone looks like
Researchers have discovered the structure of the FACT protein -- a mysterious protein central to the functioning of DNA.
DNA is like everything else: it's not what you have, but how you use it
A new paradigm for reading out genetic information in DNA is described by Dr.
A new spin on DNA
For decades, researchers have chased ways to study biological machines.
From face to DNA: New method aims to improve match between DNA sample and face database
Predicting what someone's face looks like based on a DNA sample remains a hard nut to crack for science.
Self-healing DNA nanostructures
DNA assembled into nanostructures such as tubes and origami-inspired shapes could someday find applications ranging from DNA computers to nanomedicine.
DNA design that anyone can do
Researchers at MIT and Arizona State University have designed a computer program that allows users to translate any free-form drawing into a two-dimensional, nanoscale structure made of DNA.
DNA find
A Queensland University of Technology-led collaboration with University of Adelaide reveals that Australia's pint-sized banded hare-wallaby is the closest living relative of the giant short-faced kangaroos which roamed the continent for millions of years, but died out about 40,000 years ago.
DNA structure impacts rate and accuracy of DNA synthesis
DNA sequences with the potential to form unusual conformations, which are frequently associated with cancer and neurological diseases, can in fact slow down or speed up the DNA synthesis process and cause more or fewer sequencing errors.
Changes in mitochondrial DNA control how nuclear DNA mutations are expressed in cardiomyopathy
Differences in the DNA within the mitochondria, the energy-producing structures within cells, can determine the severity and progression of heart disease caused by a nuclear DNA mutation.
More DNA News and DNA Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Clint Smith
The killing of George Floyd by a police officer has sparked massive protests nationwide. This hour, writer and scholar Clint Smith reflects on this moment, through conversation, letters, and poetry.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Graham
If former Minneapolis police officer Derek Chauvin's case for the death of George Floyd goes to trial, there will be this one, controversial legal principle looming over the proceedings: The reasonable officer. In this episode, we explore the origin of the reasonable officer standard, with the case that sent two Charlotte lawyers on a quest for true objectivity, and changed the face of policing in the US. This episode was produced by Matt Kielty with help from Kelly Prime and Annie McEwen. Support Radiolab today at Radiolab.org/donate.