Scientists have developed a new technique to rapidly and reliably detect genetic changes in malaria parasites in Ghana, using just a gaming laptop and a portable MinION sequencer from Oxford Nanopore. The technique could pave the way for local monitoring of drug resistance and evaluating new malaria vaccines in affected regions.
Malaria is a life-threatening disease caused by parasites that are transmitted to people through the bites of infected mosquitoes. According to the World Health Organization, malaria still kills over 600,000 people annually, most of which are young children in sub-Saharan Africa.
A key factor in the persistence of malaria is the ability of the parasites to rapidly evolve resistance to antimalarial drugs and other medical interventions. Genomic surveillance, the continuous monitoring of changes in the parasite’s DNA, provides the tools to analyze the genomic data behind parasite drug resistance. However, until recently, it has mostly been carried out in labs in high-income, non-malaria-endemic countries, concentrating capacity away from affected regions.
A new technique for real-time pathogen monitoring
In this new study, published in Nature Microbiology, researchers from the Wellcome Sanger Institute and University of Ghana set out to develop an accessible, near real-time technology to monitor parasite mutations within the communities most affected by malaria.
The researchers used standard molecular biology equipment for collecting parasites from blood spot samples, prepared by a simple finger prick. They then sequenced and analyzed the malaria parasite DNA using the portable MinION device and a laptop computer to detect known drug resistance markers, emerging mutations and targets of new malaria vaccines.
The team successfully carried out the study from two sites: an urban hospital in the Ghanaian capital Accra and a rural town 11-hours’ drive to the north. They were able to generate sequencing information in as little as 48 hours after receiving a sample, while keeping costs minimal, at around £27 per sample in batches of 96.
Implications for malaria control and elimination
The team showed that frontline treatments remain widely effective against local malaria strains in Ghana currently. However, ongoing monitoring is essential, including to protect high-risk groups that receive targeted interventions. They also discovered multiple genetic differences between circulating malaria strains and the protein targeted by newly recommended malaria vaccines.
The researchers hope that their technique could be adopted by local health authorities and researchers in malaria-endemic regions, enabling them to monitor drug resistance and vaccine efficacy in near real-time. This could help inform malaria control and elimination strategies, and ultimately save lives.
