PRETORIA - Medical entomologist Dr Ashley Burke describes herself as a bit of a detective, a biologist and a public health worker rolled into one. As the newest member of the University of Pretoria’s (UP) Institute for Sustainable MalariaControl, and a lecturer in the School of Health Systems and Public Health in the Faculty of Health Sciences, her role could not be more vital. 

That role takes on added significance on 20 August, with the annual observance of World Mosquito Day. The day commemorates Sir Ronald Ross, who in 1897 proved the link between mosquitoes and malaria transmission, and serves as a reminder of the urgent need to curb mosquito-borne diseases. Dr Burke’s research is part of a broader effort to protect communities from malaria and other mosquito-borne threats.

“We investigate the lives of disease vectors, not because we admire them, but because understanding them is the key tocontrolling them,” she explains. “Our work supports global health efforts, strengthens disease surveillance 

and keeps vital control tools effective. It is an honour to be part of that effort, because while mosquitoes might be small, the impact they have is huge – and the fight against them is one we simply can’t afford to lose.”

Dr Burke’s fascination with mosquitoes began with a transition to medical entomology at postgraduate level, where she focused on malaria vector mosquitoes in Southern Africa. During her master’s and PhD studies, she explored the seasonal biology of South African malaria vectors through field entomological surveillance, morphological and molecular identification of local species, incrimination of new secondary vectors species, and investigations into the effects of seasonality on vector mosquito metabolic respiration. Since then, Dr Burke has centred her work on the search for new, innovative malaria vector control tools to supplement traditional interventions.

“Working at the intersection of human health and insect biology drives my research passion,” she says. “Studying disease-transmitting arthropods to understand how they live, function and spread pathogens is crucial for refining strategies to stop them.”

The work of a medical entomologist is surprisingly varied, Dr Burke says. Some days she’ll be in the field watching thehorizon at sunset for flickers of movement to indicate a mosquito mating swarm, squelching through marshes in searchof larvae or staying up all night to catch the elusive adult female mosquitoes. Other days, she’ll be poring over her insectary-reared mosquito colonies, running insecticide bioassays or analysing DNA in the laboratory.

“In addition to all this, I have the privilege of shaping the next generation of scientists through supervising student projects and lecturing medical entomology courses,” she adds.

Medical entomologists also work closely with public health teams. They help design and test new tools to prevent mosquito bites – from bed nets and insecticides to more novel approaches such as endectocides and genetically modified mosquitoes – and monitor insecticide resistance in local vector populations to inform control programmes of the efficacy of existing tools.

“Much of our work involves understanding vector mosquito ecology: what attracts them, where they breed, when and where they bite, and more,” Dr Burke explains. “This kind of knowledge allows us to develop targeted, sustainable and cost-effective interventions.”

Vector-borne diseases are responsible for more than 700 000 deaths every year. Malaria alone accounts for over 600 000 of those deaths, most of them among young children in sub-Saharan Africa. Without effective vector control, these numbers would be far higher.

“Medical entomology sits at the heart of that fight,” Dr Burke says. “Vaccines and drugs are vital, but many vector- bornediseases have no vaccines at all, and pathogens can develop drug resistance over time. In contrast, stopping the insect vector can break the transmission cycle entirely. A mosquito that can’t bite, can’t transmit malaria.”

The challenge is that mosquitoes are resourceful, Dr Burke adds.

“They adapt quickly to changes in their environment, shift their biting times to avoid bed nets and evolve resistance toinsecticides. Without ongoing research and monitoring, control tools can lose effectiveness in just a few years. That’s why medical entomologists are constantly innovating and adapting strategies. We have to stay one step ahead of the mosquito.”

She sees medical entomology as a field where science directly serves the community.

“Every trap set, every resistance assay run, every field survey completed is part of a bigger picture: helping control programmes stay effective, guiding policy decisions and ultimately saving lives.”