mosquito

An anti-malaria breakthrough

August 26, 2025 By EarthWise Leave a Comment

The deadliest animal in the world is the mosquito. Mosquitos infected 263 million people with malaria in 2023, leading to 600,000 deaths, 80% of which were children. Malaria is caused by infection from Plasmodium parasites. The parasites are transmitted to humans from the bite of infected female mosquitos.

Researchers at the University of California San Diego, Johns Hopkins University, UC Berkeley, and the University of Sāo Paulo have developed a new method that genetically blocks mosquitos from transmitting malaria.

The study was published in the journal Nature. They used gene editing to change a single molecule within mosquitos. The genetically altered mosquitos can still bite people with malaria and can still acquire parasites from their blood, but the parasites can no longer be spread to other people. The switching of one specific amino acid known as L224 with a genetic alternative called Q224 prevents malarial parasites from reaching the salivary glands of the mosquito, thereby preventing the spread of infection. In extensive tests, the researchers found that while the genetic switch disrupted the parasite’s infection capabilities, the mosquitos’ normal growth and reproduction remained unchanged.

The hope is that the replacement of a single amino acid in mosquitoes that prevents them from being infected with malarial parasites is a beneficial trait that can spread throughout a mosquito population. The researchers believe that the trait can be spread across diverse mosquito species and populations and can pave the way for adaptable, real-world strategies to control malaria.

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Stealth Genetic Switch in Mosquitoes Halts Malaria Spread

Photo, posted June 20, 2014, courtesy of John Tann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Promising Malaria Vaccine | Earth Wise

June 23, 2021 By EarthWise Leave a Comment

Malaria is a parasitic disease transmitted through the bite of female Anopheles mosquitoes. Although the disease is both preventable and treatable, an estimated 435,000 people die of it each year, with the majority being children younger than five. Over 90% of all malaria cases and deaths occur in Africa.

The battle against malaria has mostly centered around the use of bed nets, insecticide spraying and antimalarial drugs. To date, there has not been an effective malaria vaccine available.

That may finally be changing. The first vaccinations have begun in Mali in a phase III trial of a malaria vaccine developed by the University of Oxford. The Oxford vaccine showed an efficacy of 77% over 12 months in a phase IIb trial and the hope is that the phase III trial will lead to the licensing of the vaccine in 2023.

Oxford is partnering with the Serum Institute of India for the manufacturing of the vaccine in order to be able to produce high volumes of low-cost vaccine and provide access to countries where it is required the most. The Serum Institute has committed to the production of more than 200 million doses per year once the vaccine is licensed for use, which will be an adequate supply for children most at risk of malaria in sub-Saharan Africa.

The World Health Organization Malaria Vaccine Technology Roadmap has a goal of a malaria vaccine with at least 75% efficacy. Such a vaccine is needed in order to reach the WHO’s goal of reducing malaria deaths by at least 90% by 2030.

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Promising malaria vaccine enters final stage of clinical testing in West Africa

Photo, posted June 9, 2018, courtesy of Mario Yordanov via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Natural Mosquito Repellents

June 20, 2017 By EarthWise

With summer comes mosquitoes and our desire to keep them away from us. The most common repellents are based on the chemical DEET, which unfortunately has been found to have several health and safety problems. Up to 15% of DEET is absorbed through the skin directly into the bloodstream. Diethyl-meta-toluamide, the chemical name for DEET, has been shown to have a variety of toxic effects. Fortunately, it turns out that there are some natural alternatives which may be as effective as DEET, or possibly even more effective than DEET in keeping mosquitoes away from us.

Are Mosquitoes Necessary?

March 1, 2016 By WAMC WEB

The Zika virus epidemic is yet another disease transmitted by mosquitoes. Those tiny insects are responsible for spreading many of the world’s worst diseases such as malaria, dengue fever and yellow fever. According to the World Health Organization, over 400,000 people worldwide died from malaria in 2015.