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.

We share a special episode of our podcast to mark World Mosqutio Day.

World Mosquito Day, observed annually on August 20th, commemorates British doctor Sir Ronald Ross's discovery in 1897 that female Anopheles mosquitoes transmit malaria to humans. More than a century later, major advancements like genetically modifying mosquitoes—AKA gene drives—have the potential to reduce malaria cases and deaths dramatically, but not without hurdles.

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.

People often talk about the 'malaria toolkit' - how might gene drives fit?

Transcript

When people talk about malaria, they often mention the 'malaria toolkit' – a set of tools, like bed nets and indoor residual spraying, that are available to help curb the spread of disease. In the past, these tools were trusty go-to's – thanks to their efficacy, scalability and cost. Like the antimalarial drugs used to prevent and treat the disease, they’re primarily aimed at protecting individuals. Yet, a new technology called gene drives – which releases and spreads genetically modified mosquitoes that can't transmit the disease – aims to protect whole communities. How might they fit into the toolkit? Dr Damaris Matoka-Muhia of the Kenya Medical Research Institute considers gene drives a potentially sustainable, long-term and cost-effective solution for malaria – especially as resistance dulls other tools. And in Kenya, there are regulations in place to support gene drive implementation. The National Biosafety Authority, already used for GM crops like cotton can be leveraged, ready to roll out this innovation in the future.

Source

How could genetic approaches be integrated in the malaria toolkit?

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.

Gene drives are a novel way of genetically editing the mosquitoes that transmit malaria. They have the potential to dramatically reduce cases and deaths. But the technology they’re based on is new and requires new thinking on regulation.

In this first episode of our two-part focus on gene drives, we ask how drives work – examining the CRISPR technology behind them – and explore the hurdles for their release, including the risks, regulations and questions of consent.

With Professor Anthony James (University of California, Irvine) and Dr John Connolly (Target Malaria)

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.

Gene drives are a promising tool for malaria control - how can we tell they actually work?

Transcript

Gene drives are a promising new tool for malaria control. They involve releasing genetically modified mosquitoes into the wild – mosquitoes engineered to halt the parasites from developing inside the insects, or that cause the mosquitoes to die. These GM mosquitoes are then released into new habitats. Over time and across multiple generations, the gene drive spreads, reducing malaria transmission. That’s the theory. But one fundamental question remains: how can we tell they actually work? Experts say there are three distinct measures of gene drive efficacy. First, smaller-scale trials of releases should emphasize genetic efficacy, measuring the spread and frequency of the gene drive across time and space. Then, examine entomological efficacy by measuring the density of mosquitoes or the number of parasites they carry. Finally, consider the epidemiological data, by measuring the number of malaria cases in the areas where the gene drive has been released. This approach aims to ensure that the ‘causal pathway’ of gene drives effectively reduces cases and deaths.

Source

Considerations for first field trials of low-threshold gene drive for malaria vector control

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.