Nav: Home

New model predicts substantial reduction of malaria transmitting mosquitoes

March 28, 2019

The role of mosquitoes in spreading malaria is the biggest factor behind a recent study that found them to be the 'World's Deadliest Animal'. It is particularly concerning that current measures to control them (the most important of which is the use of insecticide treated bed-nets) are losing potency as mosquitoes are evolving resistance.

The persistence of malaria in large parts of sub-Saharan Africa has motivated the development of novel tools to complement existing control programmes. These include gene-drive technologies to modify mosquito populations, either to reduce them in number or to make the mosquitoes unable to transmit disease.

In new research published today in BMC Biology, from Oxford's Department of Zoology and Oxford Martin School, a team of scientists model the potential of modifying mosquitoes with a gene-drive technology called "driving-Y chromosome" to reduce mosquito populations in a one million square km area of West Africa, including all of Burkina Faso. A driving-Y chromosome has been genetically modified so that the male mosquitoes that carry it produce predominantly male offspring (which also carry the modification). Since only female mosquitoes bite, the spread of this modification will result in less females to transmit the disease, and less mosquitoes overall.

The researchers predict that introductions of driving-Y mosquitoes will cause significant reduction of the target mosquito species in some regions and complete elimination in others.

Lead researcher, Dr Ace North, from the Department of Zoology, said: 'Gene drive holds a lot of promise for malaria control, yet the potential impact at the scale of a country has not been considered much before. We built models to help understand how a gene-drive technology could affect mosquito populations in Burkina Faso, a country with a huge malaria burden. Our results suggest it would have a major impact in reducing malaria.'

The researchers found seasonality to be the most important predictor of the local impact of the gene-drive. Population elimination is more likely in regions with mild dry seasons, while reduction is more likely in regions with strong seasonality. However, even in the most challenging environments, populations were reduced. The model suggests that this approach would have a major impact in reducing malaria.

To reach this conclusion, the scientists fed large and varied data into their models, including:
  • information of more than 40,000 settlements

  • locations of all rivers and lakes - seasonal and permanent

  • historical rainfall data

  • field data estimating mosquito population sizes and mosquito movement rates
They ran a large number of simulations on Oxford University "super-computer" facilities to explore how different factors and assumptions influence the outcome of introductions of genetically modified mosquitoes with a driving-Y chromosome.

This technology, still under development, proposes creating a driving-Y chromosome modification into the most important species of malaria mosquitoes of sub-Saharan Africa.

Professor Charles Godfray, Director of the Oxford Martin School and co-author, said: 'This study suggests that repeated introductions of modified mosquitoes over a few years into a small fraction of human settlements may be sufficient to substantially reduce the overall number of mosquitoes across the entire geographic area.'

Dr Abdoulaye Diabate, a medical entomologist at the Institut de Recherche en Science de la Santé (IRSS), Burkina Faso, said: 'There is evidence that this approach, with the right national and international approvals, could be rolled out within the next 10 years.'

The region to model was selected as it is one of the worst malaria affected areas in Africa and exhibits much of the wide variation in environmental conditions found in West Africa.

The researchers are part of Target Malaria, an international not-for-profit research consortium aiming at developing and sharing new, cost-effective and sustainable genetic technologies to modify mosquitoes and reduce malaria transmission.
-end-
For more information or to request images, please contact the University of Oxford press office at ruth.abrahams@admin.ox.ac.uk / 01865 280730.

Notes to editors

About the University of Oxford

Oxford University has been placed number 1 in the Times Higher Education World University Rankings for the third year running, and at the heart of this success is our ground-breaking research and innovation. Oxford is world-famous for research excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research sparks imaginative and inventive insights and solutions. Through its research commercialisation arm, Oxford University Innovation, Oxford is the highest university patent filer in the UK and is ranked first in the UK for university spinouts, having created more than 170 new companies since 1988. Over a third of these companies have been created in the past three years.

Target Malaria

Target Malaria is an international not-for-profit research consortium aiming at developing and sharing new, cost-effective and sustainable genetic technologies to modify mosquitoes and reduce malaria transmission. It brings together more than 130 experts from a range of scientific disciplines, risk assessment specialists and regulatory experts, stakeholder engagement and communication teams and project management experts from Africa, North America and Europe.

Source: Mosquito 'World's Deadliest Animal': https://www.gatesnotes.com/Health/Most-Lethal-Animal-Mosquito-Week

University of Oxford

Related Malaria Articles:

Breakthrough in malaria research
An international scientific consortium led by the cell biologists Volker Heussler from the University of Bern and Oliver Billker from the Umeå University in Sweden has for the first time systematically investigated the genome of the malaria parasite Plasmodium throughout its life cycle in a large-scale experiment.
Scientists close in on malaria vaccine
Scientists have taken another big step forward towards developing a vaccine that's effective against the most severe forms of malaria.
New tool in fight against malaria
Modifying a class of molecules originally developed to treat the skin disease psoriasis could lead to a new malaria drug that is effective against malaria parasites resistant to currently available drugs.
Malaria expert warns of need for malaria drug to treat severe cases in US
The US each year sees more than 1,500 cases of malaria, and currently there is limited access to an intravenously administered (IV) drug needed for the more serious cases.
Monkey malaria breakthrough offers cure for relapsing malaria
A breakthrough in monkey malaria research by two University of Otago scientists could help scientists diagnose and treat a relapsing form of human malaria.
Getting to zero malaria cases in zanzibar
New research led by the Johns Hopkins Center for Communication Programs, Ifakara Health Institute and the Zanzibar Malaria Elimination Program suggests that a better understanding of human behavior at night -- when malaria mosquitoes are biting -- could be key to preventing lingering cases.
Widely used malaria treatment to prevent malaria in pregnant women
A global team of researchers, led by a research team at the Liverpool School of Tropical Medicine (LSTM), are calling for a review of drug-based strategies used to prevent malaria infections in pregnant women, in areas where there is widespread resistance to existing antimalarial medicines.
Protection against Malaria: A matter of balance
A balanced production of pro and anti-inflammatory cytokines at two years of age protects against clinical malaria in early childhood, according to a study led by ISGlobal, an institution supported by ''la Caixa'' Foundation.
The math of malaria
A new mathematical model for malaria shows how competition between parasite strains within a human host reduces the odds of drug resistance developing in a high-transmission setting.
Free malaria tests coupled with diagnosis-dependent vouchers for over-the-counter malaria treatment
Coupling free diagnostic tests for malaria with discounts on artemisinin combination therapy (ACT) when malaria is diagnosed can improve the rational use of ACTs and boost testing rates, according to a cluster-randomized trial published this week in PLOS Medicine by Wendy Prudhomme O'Meara of Duke University, USA, and colleagues.
More Malaria News and Malaria Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#541 Wayfinding
These days when we want to know where we are or how to get where we want to go, most of us will pull out a smart phone with a built-in GPS and map app. Some of us old timers might still use an old school paper map from time to time. But we didn't always used to lean so heavily on maps and technology, and in some remote places of the world some people still navigate and wayfind their way without the aid of these tools... and in some cases do better without them. This week, host Rachelle Saunders...
Now Playing: Radiolab

Dolly Parton's America: Neon Moss
Today on Radiolab, we're bringing you the fourth episode of Jad's special series, Dolly Parton's America. In this episode, Jad goes back up the mountain to visit Dolly's actual Tennessee mountain home, where she tells stories about her first trips out of the holler. Back on the mountaintop, standing under the rain by the Little Pigeon River, the trip triggers memories of Jad's first visit to his father's childhood home, and opens the gateway to dizzying stories of music and migration. Support Radiolab today at Radiolab.org/donate.