Canadian team helps develop a low-cost solution to stop the spread of Zika
StaffGeneral Medical Laurentian University
The ovillanta design was based on a mosquito trap developed at Laurentian University in response to the outbreak of West Nile virus in northern Ontario.
A team from Canada and Mexico have joined forces to develop a low cost, environmentally-friendly device to help destroy mosquito eggs. The device has been successfully tested and the team hopes that it will help stop the spread of mosquito-borne diseases like dengue and the Zika virus.
The Canadian team designed a trap called an “ovillanta” and created a prototype for testing. The ovillanta was made from two 50 cm sections of an old tire, fashioned into a mouth-like shape, with a fluid release valve at the bottom. The lower cavity of the tire holds a milk-based, non-toxic solution developed at Sudbury’s Laurentian University lures mosquitoes. A strip is floated on the liquid where the female insect lays the eggs. The strip is removed twice weekly and the eggs destroyed using fire or ethanol.
The solution has been developed to now includes mosquito pheromone (the female insect’s chemical perfume that helps others identify a safe breeding site), is drained, filtered, and recycled back into the tire. The pheromone concentrates over time, making the ovillanta even more attractive for mosquitoes.
The 10-month study, conducted in a remote, urban area of Guatemala, documents this cheap, easy system to reduce virus-carrying Aedesgenus mosquitoes by capturing and destroying its eggs. The research team, led by Gerardo Ulibarri of Laurentian University with collaborators Angel Betanzos and Mireya Betanzos of the National Institute of Public Health of Mexico, conducted the project in collaboration with Guatemala’s Ministry of Health. Over the course of the study, the team collected and destroyed over 18,100 Aedes eggs per month using 84 ovillantas, almost seven times the roughly 2,700 eggs collected monthly using 84 standard traps in the same study areas.
Dr. Ulibarr explains that targeting mosquito eggs using the ovillanta is one third as expensive as trying to destroy larvae in natural ponds and only 20 per cent the cost of targeting adult insects with pesticides, which also harm bats, dragonflies and the mosquitoes’ other natural predators.
The ovillanta design was based on a mosquito trap developed at Laurentian University in response to the outbreak of West Nile virus in northern Ontario, which uses a modified solution to lure the Culex genus of mosquito, the West Nile carrier thought by some to be also the Zika carrier.
“We decided to use recycled tires – partly because tires already represent up to 29 per cent 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,” said Dr. Ulibarri.
The Aedes genus of mosquito – the principal genus that transmits Zika, dengue, chikungunya, and yellow fever viruses – has proven extremely difficult to control using other strategies, according to the World Health Organization.
“Innovation is a key driver underlying the Government of Canada’s approach to international development,” said Canada’s Minister of International Development and La Francophonie, the Honourable Marie-Claude Bibeau. “Innovative solutions that deliver improved global health outcomes – such as for the fight against the Zika virus – are needed.”