Understanding Pf7

Malaria is caused by a parasite, not a virus or bacterium — a single-celled organism called Plasmodium, carried from person to person by mosquitoes. Of the species that infect humans, Plasmodium falciparum causes the most severe disease and the majority of malaria deaths worldwide. Understanding how this parasite changes over time and place is central to controlling it.

That's where Pf7 comes in.

What is Pf7?

Pf7 is a large, openly available dataset describing genetic variation across thousands of P. falciparum samples. It was published in 2023 by MalariaGEN, a collaborative research network that brings together scientists from research institutions around the world to share malaria genomic data openly, rather than each group working in isolation with their own private datasets.

The dataset contains 20,864 samples, gathered by 82 partner studies across 33 countries, with collection dates spanning from 1984 to 2018. This breadth matters: malaria doesn't behave the same way everywhere, and a parasite population in Southeast Asia can look genetically quite different from one in West Africa. A dataset this large and geographically wide-ranging lets researchers compare parasite populations across regions and across decades, rather than drawing conclusions from a single time and place.

Why genetic data matters for malaria control

Every time a parasite reproduces, small changes can appear in its genetic code. Most of these changes are inconsequential, but some matter enormously — particularly changes that help the parasite survive the drugs used to treat it, or evade the diagnostic tests used to detect it.

Genome variation datasets like Pf7 let researchers track these changes at scale. Rather than studying one clinical outbreak at a time, scientists can look for patterns across tens of thousands of samples: where are drug-resistance markers appearing? Are they spreading between regions? Are there mutations that might make certain rapid diagnostic tests less reliable?

Pf7 also includes samples sequenced using a newer technique that allows genetic material to be extracted from dried blood spots — a much simpler, cheaper collection method than the venous blood draws earlier datasets relied on. This matters practically: it opens the door to including samples from areas or studies that previously couldn't easily contribute genetic data at all.

Open data as a research strategy

Perhaps the most significant thing about Pf7 isn't any single scientific finding, but the fact that it's freely available to anyone, published under a Creative Commons Attribution licence. Any researcher, anywhere, can download the dataset without negotiating access agreements or paying fees.

This matters because malaria overwhelmingly affects some of the least-resourced regions and research communities in the world. Open data lowers the barrier for local researchers to work with genomic information collected in their own countries, rather than that data being accessible only to institutions with the resources to generate or license it themselves.

What's next

Pf7 has since been followed by an even larger release, Pf8 — you can read about that in our companion article, Understanding the Pf8 dataset. You can also explore the Pf7 sample data directly, including where and when samples were collected, on the Pf7 dataset page.