More than just malaria

Researchers can change children’s futures in many more ways than just helping to beat a killer disease, Cristina Ariani discovered

By: Ali Cranage, science writer at the Wellcome Sanger Institute

The outskirts of Navrongo in Ghana, where Cristina met a child who opened her eyes to the wider needs of people living in malaria-affected regions

Cristina Ariani was on the outskirts of Navrongo, a town in Northern Ghana, to set up a malaria research project, when she started chatting to a group of young children playing nearby. One of her colleagues asked them why they weren’t in school that day. One of the girls replied: “I don’t have a pen.” Cristina immediately handed over hers.

Ever since then, Cristina has combined her research into the genetics of malaria with fundraising to help communities in Ghana and beyond. She has raised money for both school supplies and insecticidal bed nets – the main way to prevent malaria infection.

Rice fields between Chiana and Navrongo - where mosquitoes breed
Rice fields between Chiana and Navrongo, Ghana – where malaria-carrying mosquitoes breed

There were 219 million cases of malaria worldwide in 2017, according to the WHO. Cristina says many of the people she met in Navrongo couldn’t tell you how many times they’d had it. It was several times a year, every year; a part of life there as it is in many areas of the world.

Some people develop a type of immunity, and symptoms of infection can become mild. But in other cases it can be deadly. There were 435,000 deaths around the world from malaria in 2017, most of them children.

Collecting samples: lights, sprays and legs

Local malaria researchers Victor Asoala (left) and Lucas Ameng-Etego (right) with Sanger Institute researcher Cristina Ariani (middle)
Local malaria researchers Victor Asoala (left) and Lucas Ameng-Etego (right) with Sanger Institute researcher Cristina Ariani (middle)

Cristina worked with local researchers in Navrongo, who collected samples of the parasites that cause malaria. The parasites live in people (in blood and in the liver) and in mosquitoes, which transmit them between their human hosts. To get a full picture of the local population of parasites, the team need to gather samples from both.

To collect parasites from people, the team worked with the local clinic that treats those with mild infections. They only need a tiny blood sample from a patient, usually from a finger prick. The sample is collected on filter paper and can be easily transported back to the Wellcome Sanger Institute.

Collecting mosquitoes isn’t so straightforward. Cristina explained that there are three main ways:

Mosquito light trap - one way to catch malaria-carrying mosquitoes
Mosquito light trap – one way to catch malaria-carrying mosquitoes

“You can use a light trap, which is placed in a bedroom overnight. Or you can spray a bedroom with insecticide in the morning. But these methods may not get a full representation of the population, because some mosquitoes might be resistant to the insecticide, or not fall into the trap.”

The third option uses people as live bait. Working in small groups overnight, two people will sit outside a house, and wait for the mosquitoes. They are mostly covered, but leave their legs bare. They collect any mosquito that bites, or attempts to bite them. Workers swap over every 30 minutes throughout the night, alternating resting inside the house with sitting out in the dark. It isn’t a fun job, but it is effective.

Know thy enemy: DNA analysis

Once the samples are collected, they are shipped back to the Sanger Institute for genomic testing. Parasite and mosquito DNA is extracted, sequenced and analysed.

Sequencing machines processing malaria DNA at the Sanger Institute
Sequencing machines processing malaria DNA, at the Sanger Institute

The information in the DNA could help inform decisions about which insecticides, antimalarial drugs and other control measures should be used, as well as how and where to use them. The knowledge is a key part in the battle against the rapidly evolving parasites.

For example, genomic information can identify transmission hotspots, where the parasite is rapidly moving from host to host. This can help focus control efforts in the right place. Genomic analysis can also identify drug and insecticide resistance – helping public health officials decide which treatments to use in any particular area. It can monitor the effects of a control measure, for example to see if parasites are becoming resistant to an antimalarial drug that has been used. The data can also show if parasites are migrating in from outside the region.

DNA analysis is sent back to the local researchers in Navrongo, who use the data to conduct their own studies in malaria and its transmission

The data from this genomic analysis goes back to the local partners in Navrongo. The work is part of SpotMalaria, which has similar collaborations all over the world. As well as helping to inform control efforts, partners in Navrongo are able to use the data in their own additional research too. The analysis feeds into wider research at the Sanger Institute too; studies into the evolution of the parasite and research to develop new treatments.

Making a difference: pens, bednets and classrooms

Cristina has made a real difference to lives in Navrongo. Since 2016, she has fundraised for school supplies and stationery and has supplied enough for 6,000 children in the region. She has also raised money to renovate a classroom. This year she is raising cash to supply insecticidal bed nets to protect people from malaria. To donate, visit the Against Malaria Foundation.

“As a scientist you want to find out how things work,” Cristina said. “You want to find out why things are the way they are. With malaria, there is an extremely interesting biological challenge. The parasite is a fascinating organism. But also working on it has public health implications; the parasite can have a devastating effect on people and communities. Our work has the potential to change that and make a real difference.”

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