Canadian innovation for killing mosquito eggs could help Zika fight

Grand Challenges Canada

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Video: bit.ly/1S3YFjH

Canadian Government-supported researchers use mosquitoes’ own perfume to lure them to lay eggs in trap; Sudbury-based scientist leads project in Guatemala

OvillantaWith Canadian Government funding, a team of innovators from Canada and Mexico have successfully tested a low cost, environmentally-friendly way of destroying the eggs of the mosquito genus that spreads dengue, and likely spreading the Zika virus.

The 10-month study, conducted in a remote, urban area of Guatemala, documents a cheap, easy system to reduce virus-carryingAedesgenus mosquitoes by capturing and destroying its eggs. The results appear today in the F1000Research Zika & Arbovirus Outbreaks channel: bit.ly/1P3chwX *.

The system includes an innovative Canadian-designed trap called an “ovillanta,” created from two 50 cm sections of an old car tire, fashioned into a mouth-like shape, with a fluid release valve at the bottom.

Inside the lower tire cavity, a milk-based, non-toxic solution developed at Sudbury’s Laurentian University lures mosquitoes. Inserted to float in the artificial pond is a wooden or paper strip on which the female insect lays her eggs. The strip is removed twice weekly, analyzed for monitoring purposes, and the eggs destroyed using fire or ethanol.

The solution, which now includes mosquito pheromone (the female insect’s chemical perfume that helps others identify a safe breeding site), is then drained, filtered, and recycled back into the tire. The pheromone concentrates over time, making the ovillanta even more attractive for mosquitoes.

With a grant from Grand Challenges Canada, funded by the Government of Canada, the researchers, 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.

They found the rubber ovillanta significantly more effective at attracting the Aedes mosquito than standard traps made from 1-litre buckets.

During the 10-month study, the team collected and destroyed over 18,100 Aedes eggs per month using 84 ovillantas in seven neighbourhoods of the town of Sayaxche (population 15,000), almost seven times the roughly 2,700 eggs collected monthly using 84 standard traps in the same study areas.

A tantalizing but anecdotal observation was that there were no new cases of dengue reported as originating in the ovillanta study test area, a community that would normally anticipate two or three dozen cases in that timeframe.

Targeting mosquito eggs using the ovillanta, Dr. Ulibarri says, is one third as expensive as trying to destroy larvae in natural ponds and only 20% the cost of targeting adult insects with pesticides, which also harm bats, dragonflies and the mosquitoes’ other natural predators.

The ovillanta was modelled after 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% 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.

Key to the overall system is an online training program to strengthen the mosquito control expertise of local health workers, coupled with a community engagement strategy that involves households in the regular maintenance of their ovillanta.

The community members collect the egg-laden strips of paper or wood from the ovillanta and pass them to the health workers, who conduct the monitoring and destruction using fire or ethanol.

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.

A female, with a natural lifespan of up to three months, can start to reproduce in one week. Pesticide-resistance, dwindling resources, and an increase in mosquito-friendly environments have thwarted traditional methods of controlling the insect’s rapid spread.

“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.”

“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,” said Dr. Peter A. Singer, Chief Executive Officer of Grand Challenges Canada.

High-res still photos: bit.ly/1RxJZ1O

Researchers’ how-to video for creating an ovillanta: bit.ly/1S3YFjH

Video of an ovillanta under construction in Guatemala: bit.ly/25jlxVW

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(* This paper is posted pending peer review, consistent with the open data approach proposed by the World Health Organization for Data Sharing in Public Health Emergencies: bit.ly/1QIEUx7)

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About Grand Challenges Canada

Grand Challenges Canada is dedicated to supporting Bold Ideas with Big Impact in global health. We are funded by the Government of Canada and we support innovators in low- and middle-income countries and Canada. The bold ideas we support integrate science and technology, social and business innovation – we call this Integrated Innovation. Grand Challenges Canada focuses on innovator-defined challenges through its Stars in Global Health program and on targeted challenges in its Saving Lives at Birth, Saving Brains and Global Mental Health programs. Grand Challenges Canada works closely with Canada’s International Development Research Centre (IDRC), the Canadian Institutes of Health Research (CIHR) and Global Affairs Canada to catalyze scale, sustainability and impact. We have a determined focus on results, and on saving and improving lives. http://www.grandchallenges.ca

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News release in full, click here

Example coverage by:

Agence France Presse, Cheap tire innovation could boost Zika control, click here; in French, “Zika: un piège à moustiques plus efficace, écologique et bon marché, click herePortuguese, click here; Japaneseclick here

ABC News, USA: Using Old Tires to Fight Zika Virus: Canadian Government Funds DIY Mosquito Trap, click here

The Canadian Press, Old tires a new weapon against spread of Zika, click here

CBC Radio As It HappensHow this Canadian-designed mosquito trap could help fight Zika virus, click here

Toronto Star, A Canadian team is testing a $4 hack to solve the Zika crisis, click here

Globe and Mail, Canada, Canadian researcher’s mosquito trap offers hope in fight against Zika spread, click here

The Huffington Post, Canada, Cheap Tire Trap Could Help Fight Zika Virus, click here

Gizmodo, USA and India, This Low-Tech Trap For Killing Mosquito Eggs Is Brilliant, click here

The Weather Network, Canadian team set to turn tires against Zika virus, click here

TreeHugger, USA, Mosquito traps made from old tires 7 times more effective than standard traps

Agencia EFE, Spain, Un método barato para combatir el mosquito Aedes aegypti podría reducir el zika, click here

Agencia Brasil, Cientistas fazem armadilha mais eficaz contra o a adeusa (Scientists make a more effective trap for Aedes), click here

IRIN News, Iran, Persian: روش عجیب کانادا برای مقابله با بیماری مرگبار زیکا (Canada novel way to deal with the deadly disease Zika), click here

Thanh Niên, Vietnam, Cách chống dịch Zika rẻ tiền bằng vỏ ô tô cũ và sữa, click here

Sciences et Avenir, France, Zika: un piège à moustiques plus efficace, écologique et bon marché (Zika: a more effective mosquito trap, environmentally friendly and cheap), click here

Sudbury Star, Sudbury-designed traps could help stop Zika, click here

Motherboard VICE, How Canadian Scientists Plan to Fight Zika With Old Tires and Milk, click here

Daily Beast, USA, Fighting Zika Mosquitos with Tires, click here

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Full coverage summary, click here