Writes Bilal Mpembamoto

In the heart of rural Tanzania, scientists are on a mission to outsmart mosquitoes, one of the world's most notorious nuisances. They're using something sweet and sticky to attract these buzzing critters, but not in the way you might think. This story is about Attractive Targeted Sugar Baits (ATSBs) and how researchers are using high-tech camera traps to see if these baits really work.

The sweet experiment

Imagine a large cage, big enough for a small room, filled with mosquitoes. Here at the Kilombero Valley in Morogoro, Tanzania, Ifakara Health Institute scientists set up different types of baits: one with an attractant, one without (just to see if mosquitoes would visit anyway), and another with plain sugar water. They wanted to know if mosquitoes would prefer the bait with the special attractant. 

Using specially designed camera traps, they took pictures every minute for three days. What they found was fascinating! More mosquitoes, especially the anopheles funestus, flocked to the attractant bait than to the plain one. Both male and female mosquitoes were interested, but female anopheles funestus seemed particularly drawn to it. 

From cage to countryside

The real test, however, was in the Tanzanian countryside. Here, 16 camera traps were set up in homes, mimicking the conditions of the experiment. Seven homes had the attractant bait, seven had blank bait, and two had just sugar water. To compare, they also used a traditional method called Human Landing Catch (HLC), where people count how many mosquitoes land on them.

The results – published on the BMC’s Parasites & Vectors journal recently – were clear: mosquitoes loved the attractant bait much more than the others. On average, 70 anopheles arabiensis mosquitoes were caught per person in HLC, but only one was caught with the baits. 

Yet, the cameras showed that mosquitoes visited the attractant baits more often than the blanks or the sugar water. Again, more females than males were drawn to these baits, with anopheles arabiensis being the most frequent visitors.

What does this mean?

This study – led by Ifakara scientist Felician Meza as lead author – tells us that camera traps are great tools for understanding mosquito behavior. They help scientists see which baits work best without having to rely on traditional, more invasive methods. 

By knowing which baits mosquitoes can't resist, we can better design strategies to control these disease-carrying insects, potentially reducing the spread of diseases like malaria.

The future of mosquito management

The journey of these camera traps doesn't end here. With this knowledge, Meza and colleagues behind this study believe, researchers can refine ATSBs, making them more effective in real-world scenarios. This could mean fewer mosquitoes, less disease, and a safer environment for people living in mosquito-prone areas. 

So, next time you swat at a mosquito, remember: there's a quiet battle being fought with science, cameras, and sweet baits in far-off places, all to keep these tiny pests at bay.

_______

Bilal Mpembamoto heads the Communications Office at the Ifakara Health Institute. He’s an experienced science writer and media editor, having worked for reputable media outlets in Tanzania, including The Guardian and Mwananchi Communications.