High-tech devices catch mosquitoes one by one

Hidden in overgrown backyards and piles of old tires, dotted around Houston, are what look like ten tiny models of Hollywood’s iconic Capitol Records building.

They are full of recording gear, but not to capture the vocals of Frank Sinatra or the Beastie Boys.

These high-tech devices catch mosquitoes — though not in big batches, like typical traps. They catch them one by one, each in its own compartment, after inspecting each mosquito’s wing beats to be sure it’s a species that researchers want.

“We were the first to have these,” said Mustapha Debboun, Director of mosquito control for the Harris County public health department. “I saw something on the internet about them, and I said, ‘Whoa — can I get some?’

“They’ve been wonderful,” he added. “Why would I want to collect a thousand nuisance mosquitoes if I can avoid it?”

The new traps, made by Microsoft, overcome one of the most frustrating aspects of insect surveillance: There are 56 species of mosquitoes in this buggy bayou city, and conventional traps suck in nearly all of them.

Entomologists want only a few disease-carrying types, including Aedes aegypti, which carries Zika and dengue, and Culex quinquefasciatus, which spreads West Nile virus.

To find them, scientists must freeze whole batches caught in the usual traps and tediously hand-sort them with tweezers under a microscope.

Making matters worse, most traps suck the insects through a fan and then whirl them around a mesh basket for hours.

“The white scales get rubbed off, so you lose the white lyre on the back that tells you it’s aegypti,” said Pamela Stark, a county entomologist. “June bugs get pulled in and stomp around like cows.”

The Microsoft trap, by contrast, has 64 compartments, arrayed like studio apartments in a skyscraper.

When an insect flies in, it crosses an infrared beam that reads the pattern of the shadows thrown by its buzzing wings, said Ethan Jackson, a computer scientist who leads Microsoft’s Project Premonition, which created the trap with advice from mosquito experts at the Bill and Melinda Gates Foundation.

If it’s a species the county wants, a clear plastic door shuts “like a Venus fly trap,” Dr. Jackson said. The trap can catch the right species almost 90 percent of the time.

Each compartment also records and uploads to a website the time, temperature, humidity and ambient light — data that records when each species hunts for blood, which is a good time to spray.

The first 30 prototypes, of which Houston has 10, cost several thousand dollars each, Dr. Jackson said. But he hopes to get the price down below $300, so even poor countries where malaria and yellow fever kill thousands of victims could afford them.

Selling traps is not the point, he explained. He has a far more ambitious goal: to have thousands of them around the world gathering viral DNA the way Google Street View gathers pictures — for the value of the data.

He was thinking about Ebola’s long migration from central Africa to Guinea, he said, when he had an idea.

Animals are full of diseases that infect humans, but it’s tricky to get blood samples from gorillas, migrating birds, cave-dwelling bats, poisonous snakes and so on.

“Then I realized that’s a mosquito’s full-time job,” Dr. Jackson said. “There are over 3,600 species, but if we can catch the right ones and do metagenetic sequencing on all the DNA and RNA we find in them, we can see the diseases on the move.”

Research efforts like the Global Virome Project are trying to find and sequence every virus that might threaten mankind.

Mosquitoes, he suggested, could make that go much faster “by being their field biologists.”

Source The New York Times

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