Researchers search for ways to predict antimalarial drug resistance and identify more effective drug combinations.

Transcript

The front-line treatment for malaria is typically a combination of drugs called artemisinin-based combination therapy. Resistance to treatment has already been reported in mild cases of malaria, but now, for the first time, it’s also being reported in severe cases of malaria. Severe malaria cases are more likely to end in a fatal outcome, so drug resistance in these scenarios poses a risk to human life. To try and stay one step ahead of resistance, researchers tested compounds and combed through publications to identify 118 compounds active against over 700 parasite clones to see how the parasites evolve under pressure, and to identify mutations in the parasite genome likely to be associated with drug resistance. They confirmed that Plasmodium falciparum – the deadliest and most prevalent species of the malaria parasite – evolves relatively easily, with mutations that affect the drug’s mechanism of action and which move through the population. The hope is that this dataset of drug resistance markers could provide an ‘early warning system’ – to predict drug resistance in the field and to identify a more effective drug combination.

Source

Artemisinin Partial Resistance in Ugandan Children With Complicated Malaria (JAMA)

Systematic in vitro evolution in Plasmodium falciparum reveals key determinants of drug resistance (Science)

About The Podcast

The Johns Hopkins Malaria Minute podcast is produced by the Johns Hopkins Malaria Research Institute to highlight impactful malaria research and to share it with the global community.

The World Health Organization has today released its annual World Malaria Report. Here are the takeaways.

Transcript

The World Health Organization has today released its annual World Malaria Report. Here are the takeaways. Since the turn of the century, the global malaria community has averted over 2.2 billion malaria cases and 12.7 million deaths, with over a million deaths prevented in 2023 alone. Yet, despite significant progress, major gaps remain. In 2023, there were 263 million malaria cases globally, up 11 million from the year before, and nearly the same number of deaths. This means we’re off course against key WHO targets, with the case rate amongst at-risk populations three times higher than hoped, and a funding gap of over $4bn. It’s hoped that a ‘Big Push’ of political and capital commitment could accelerate efforts against the disease, help overcome drug and insecticide resistance, and improve access to new bed nets, drugs, and vaccines. But, as ever, this is dependent on funding, political will, and as this year’s report notes, a special focus on equity. There’s a need to disaggregate data to reveal the nuances of malaria transmission and understand how the disease intersects with gender equality, health equity and human rights.

Source

World malaria report 2024

About The Podcast

The Johns Hopkins Malaria Minute podcast is produced by the Johns Hopkins Malaria Research Institute to highlight impactful malaria research and to share it with the global community.

An innovative, non-invasive diagnostic tool that could revolutionize malaria testing, with the potential to be built into wearable devices.

In this extended episode of the Johns Hopkins Malaria Minute, we ask:

• What are the limitations of current malaria diagnostic methods?
• How is a 'cytophone' - and what makes it innovative?
• Why is the detection of hemozoin significant in malaria diagnostics?
• How does interdisciplinary collaboration contribute to technological innovation?

With Sunil Parikh, Vladimir Zharov and Yap Boum

About The Podcast

The Johns Hopkins Malaria Minute is produced by the Johns Hopkins Malaria Research Institute to highlight impactful malaria research and to share it with the global community.

Using lasers and ultrasound, the ‘cytophone’ detects a key byproduct of all malaria parasites.

Transcript

Among the most commonly used malaria diagnostic tests is the rapid diagnostic test (RDT), which detects malaria antigens from a drop of blood. Whilst RDTs are small and cheap, they're invasive and new strains of the parasite have evolved that can escape RDT diagnosis. Now, engineers have developed new diagnostic technology – a cytophone – which doesn’t require a blood draw. About the size of a desktop printer, the cytophone uses lasers and ultrasound to detect infected red blood cells in the vein on a patient’s hand or forearm. The cytophone works by detecting hemozoin, a byproduct of all malaria parasites from their consumption of hemoglobin for energy. When hemozoin absorbs a certain amount of the laser energy, it heats up and expands, generating ultrasound waves that indicate malaria infection within the red blood cell. In a trial of 20 adults in Cameroon with symptomatic malaria, the cytophone prototype performed as well as current point-of-care diagnostic methods.

Source

Noninvasive in vivo photoacoustic detection of malaria with Cytophone in Cameroon

About The Podcast

The Johns Hopkins Malaria Minute podcast is produced by the Johns Hopkins Malaria Research Institute to highlight impactful malaria research and to share it with the global community.

Today, how DNA from a single patient in Ethiopia can shed light on the big picture of malaria.

• Why is Plasmodium vivax significant in malaria research, especially in Ethiopia?
• How does genomic sequencing contribute to understanding and controlling malaria?
• How are advances in sequencing technology influencing malaria research?

With Jane Carlton, Delenasaw Yewhalaw, and Francisco Callejas Hernandez

About The Podcast

The Johns Hopkins Malaria Minute is produced by the Johns Hopkins Malaria Research Institute to highlight impactful malaria research and to share it with the global community.

'Comparative genomics' helps identify genes that can serve as targets for future drugs and vaccines.

Transcript

Not all parasites are alike. Genetic mutations mean that malaria parasites evolve differently in different regions – and even within the same region. One species thought to be particularly genetically diverse is Plasmodium vivax. It’s the second most common species of malaria, found in South East Asia, South America, and some parts of Africa. In Ethiopia, 20% of malaria cases are thought to be caused by P. vivax. In a new paper, scientists made a ‘reference genome’ from a sample of P. vivax in Ethiopia. They collected blood from an infected patient, extracted the DNA, and ‘read’ its fragments to form the parasite genome. This allows scientists to compare P. vivax samples across regions – and understand their similarities and differences. Importantly, this study of ‘comparative genomics’ ie comparing genomes will help identify the genes that stay the same – the conserved genes – and those which are different - the unique genes -which could serve as targets for future drugs and vaccines.

Source

Assembled genome of an Ethiopian Plasmodium vivax isolate generated using GridION long-read technology

About The Podcast

The Johns Hopkins Malaria Minute podcast is produced by the Johns Hopkins Malaria Research Institute to highlight impactful malaria research and to share it with the global community.

The World Health Organisation has recommended two licenced malaria vaccines. Those vaccines have been a long time coming - but are they the best?

In this extended episode of the Johns Hopkins Malaria Minute, we ask:

• Why is developing a malaria vaccine so challenging?
• How does antigen variation play affect the effectiveness of malaria vaccines?
• What are transmission-blocking vaccines (TBVs), and why haven't they gained much interest despite their potential?

With Ilinca Ciubotariu, Qixin He and Giovanna Carpi.

About The Podcast

The Johns Hopkins Malaria Minute is produced by the Johns Hopkins Malaria Research Institute to highlight impactful malaria research and to share it with the global community.

A key challenge in developing a malaria vaccine is choosing which stage to target.

Transcript

A key challenge in developing a malaria vaccine is choosing which stage of the infection to target. You can target the parasite when it enters the body, multiplies in the liver and the blood, or is in the sexual stage, preparing to be picked up by a mosquito. Along with selecting the right vaccine target, it’s also important to consider how these targets naturally vary in the population. To identify the optimal target, researchers examined the genetic and structural variation of ten antigens in over 1,000 samples of malaria parasites from six African countries. Interestingly, antigens involved in human infection showed the most genetic and structural variation across countries. Transmission-blocking antigens—ones that induce antibodies in humans that disrupt the parasite’s development in the mosquito, thus preventing further transmission —were more conserved across regions. This makes transmission-blocking antigens excellent targets as standalone or multi-stage vaccines to prevent onward transmission to other people.

Source

Diversity and selection analyses identify transmission-blocking antigens as the optimal solution.

About The Podcast

The Johns Hopkins Malaria Minute podcast is produced by the Johns Hopkins Malaria Research Institute to highlight impactful malaria research and to share it with the global community.