World Malaria Day 2024
How researchers from the global North and South aim to curb malaria

A research collaboration between Europe and Africa sets out to genetically monitor malaria parasites

Progress against malaria is at risk. In 2022, nearly 250 million people contracted malaria and more than 600,000 people, mostly children, died from the infection. Since 2007, World Malaria Day has been dedicated to raising awareness of the disease, the challenges and successes in controlling it. Scientists Jason Hendry and Mulenga Mwenda are using their research to tackle an urgent problem in the fight against malaria, as malaria parasites that have developed resistance to current drugs are spreading across African countries.

There was reason for optimism in the fight against malaria. A combination of new drugs and the distribution of insecticide-treated bed nets began to show results in the 2000s, with a slow but steady decline in infections and deaths. However, this progress has stalled as the malaria parasites adapt to these control strategies. For example, a form of the parasite that is resistant to the standard malaria drug artemisinin is spreading in Southeast Asia. Resistant parasites are a particular problem in African countries, where the burden of disease is highest and the most deaths occur.

These resistances call for new approaches in the fight against malaria. This is what Jason Hendry of the Max Planck Institute for Infection Biology in Berlin and Mulenga Mwenda of the non-profit PATH in Lusaka, Zambia, are working on. The scientists have developed a new method to obtain information about the parasite genome from the blood of malaria patients. In doing so, the team hopes to achieve multiple goals: to monitor the spread of malaria parasites and to provide African scientists with mobile and cost-effective methods that can be used and developed in local laboratories.

Deciphering drug resistance from the parasite genome

“If you don't know what's going on, you can potentially make the problem worse by using drugs in an area where there is resistance,” explains Jason Hendry, who initiated the project with colleagues from the University of Oxford in 2019. Hendry and Mwenda's team believe that it is essential to know where resistant parasites are located. Only then can measures be taken to prevent their spread.

Whether a parasite is resistant to a drug can be determined from its genetic material. Until now, however, DNA sequencing, the reading of genetic material, could only be carried out in specialized facilities. The expertise required and the technology involved are expensive. For this reason, smaller local laboratories in many African countries have to send their samples internationally. Valuable time passes before the results are back. Time that could have been used to act against the spread of resistant parasites and improve malaria control. “The widespread use of antimalarial drugs puts pressure on malaria parasites to evolve resistance. We have to be able to work at the same speed or we will fall behind,” says Hendry.

Reading out the parasite genome: Compact, inexpensive and fast

Mwenda and Hendry have developed a protocol for DNA sequencing of malaria that can provide valuable information on resistance within three days on the spot. The protocol uses a DNA sequencing device called the “MinION”. It is no bigger than a smartphone and costs approximately €1000, more than a hundred-times cheaper than conventional sequencing machines. A single drop of blood from a malaria patient, dried onto a piece of filter paper, is all it takes to read the parasite's genome. The “MinION” was released in 2015 by Oxford Nanopore Technologies and is based on the concept of nanopore sequencing: DNA is passed through a tiny pore and the sequence of letters are read by measuring a change in current.

However, detecting resistance in the genetic material of malaria parasites requires many more steps, including laboratory preparation of blood samples and extensive data analysis. Since 2019, Hendry has been working with several African countries, such as Zambia, Nigeria and Kenya, to apply and improve the method with local scientists— combining both research and implementation in a shared process. “Transferring the technology and knowledge to them is important so that there is more ownership of the data and the actual process, and the results can be integrated more quickly into malaria control programs,” explains Hendry.

Essential North-South collaborations

North-South collaborations are essential for their approach. “There is no malaria in Germany, the UK or the USA, but there is a lot of technical expertise,” emphasizes Hendry. “Researchers in Africa, on the other hand, have a far greater understanding of the epidemiological context, local problems, local priorities and the geography—they understand the disease far better than we ever will.”

In the long term, every country in Sub-Saharan Africa should be able to carry out its own surveillance of drug resistance without having to send samples internationally. After all, there can be no one-size-fits-all solution for an entire continent where there are very different malaria parasites with different resistances in different places. At the same time, the parasites do not stop at national borders. For Hendry and Mwenda the goal is to provide comprehensive surveillance by an international network.

A long way to go

But there is still a long way to go. One challenge researchers in African countries face is the procurement of reagents and materials. Distributors make ordering expensive and time-consuming. “In many cases, the supply chain can be slowest part of establishing routine DNA sequencing.” says Hendry. Nevertheless, the scientists want to tackle these problems: If the researchers continued to send out all samples, there would be no incentive to improve supply chains in African countries and thus reduce inequalities.

The most important question for the future, however, is what to do with the information gathered. Only if the right epidemiological decisions are made in a timely manner and the right countermeasures are taken to combat resistance can the approach be successful. “In the near future we will tailor how we combat malaria based on observations from the surveillance data, using approaches like nanopore sequencing” explains Hendry.

In summary, Hendry and Mwenda's research exemplifies the necessity for innovative approaches and international collaboration in the fight against malaria. When researchers combine local knowledge with technical innovation, they can develop effective strategies to monitor and contain resistant parasites. In partnership, researchers from both the global South and North can help contain the spread of malaria and save lives.