Fighting Zika Mosquitos With Tires
Researchers built a cheap, easy, and successful solution to mosquitos carrying Zika virus.
With 33 countries in the Americas now identified as carrying the Zika virus, the need for a solution to the epidemic is great. But with limited funds in the regions where it’s spreading the fastest, the need for a cost-effective one is even greater.
Thanks to the creativity of some researchers in Canada and Mexico, we may have just landed one. In a study released Thursday morning, researchers revealed a cost-effective mosquito trap capable of killing tens of thousands eggs in a matter of months—using spare car parts.
Named the “ovillanta,” the device is essentially a mosquito trap made of two sections of a recycled car tire. Cut into half circles, the two pieces are molded into a mouth-like shape, the bottom of which is filled with a milk-based solution that attracts mosquitoes. A valve to release liquid sits at the base of the ovillanta, allowing the researchers to drain and filter the device.
Mosquitos have long thrived in the inside section of tires. Capable of containing heat, holding water, and collecting organic rain matter, tires form an ideal breeding ground for mosquitos—an incubator of sorts where female mosquitos can safely reproduce. The Aedes aegypti mosquito—which carries Zika, among other infectious diseases—particularly love tires.
“We have dragged mosquitoes around the world in billions of used tires,” Paul Reiter, a French professor of medical entomology, told The New Yorker in 2012. He’s right. In 1985, when a large population of Aedes albopictus mosquitoes were discovered in Houston, Texas, officials traced it to tires arriving from Japan. Since then, researchers have tracked similar instances across the globe.
Using the appeal of tires to mosquitoes, the Canadian and Mexican researchers found a way to beat the bugs at their own game. The tires attract the mosquitos into the ovillanta, where researchers create a pseudo “pond” inside—a perfect place to lay eggs. At the bottom of it is a strip of paper to collect the eggs. Every few days, the researchers removed the strip and destroyed the eggs.
After filtering the liquid, they reintroduced it into the ovillanta, allowing the pheromone that female mosquitos release when laying eggs to attract even more mosquitoes. This pheromone, a sort of perfume that the female releases, lets others know that it’s safe to lay eggs. In other words—the longer it’s used, the more appealing and successful it becomes.
Using 84 ovillanta over a 10-month span in Guatemala, the researchers destroyed more than 18,000 Aedes mosquito eggs. The typical traps in the area, made of 1-liter buckets, only collect around 2,700 eggs per month—seven times less than the ovillanta. Beyond the efficacy of the trap, it’s easy and cheap to make.
Plus, made up of old tires, a milky liquid, and paper stripes, it’s an extremely cost-effective solution. Underneath the study, the researchers posted a link explaining to health workers how they can construct the ovillantas themselves. Dr. Gerardo Ulibarri of Laurentian University, the lead researcher on the study, says the trap was inspired by a similar concept used during the West Nile virus in Ontario
He says the decision to make this trap out of tires was three-fold. "We decided…partly because tires already represent up to 29 percent of the breeding sites chosen by the Aedes aegypti mosquitoes, partly because tires are a universally affordable instrument in low-resource settings, and partly because giving old tires a new use creates an opportunity to clean up the local environment.”
Funded by the Canadian government, the project aims to involve community members who can collect the paper strips and deliver them to health workers. Using an online training program to educate local health workers on mosquito breeding, the researchers hope to start changing the tide of the Zika outbreak.
“While in its early days, this integrated innovation of a mosquito trap coupled with training local health workers and engaging communities in vector control is a promising example of how Canada’s leadership in development innovation can respond to public health emergencies such as Zika,” CEO of Grand Challenges Canada Dr. Peter A. Singer said.
Whether or not the trap will prove the end of the Zika outbreak remains to be seen. But with the scientific community reaching a consensus on the connection between the virus and the birth defect microcephaly, it’s absolutely worth a try.