“We have two,” says Lamar\u00a0Rush, examining a mosquito trap with a magnifying glass. “So far.”<\/p>\n
\nRush, operations director for the City of Long Beach’s vector control program,\u00a0has set dozens of traps for his tiny, potentially dangerous prey: Aedes aegypti, the main mosquito behind the spread of the\u00a0Zika virus, a disease associated with microcephaly in infants. It prefers to live in and around houses, side-by-side with its preferred food\u00a0source: humans.<\/p>\n
\n\n ![\"Mosquitos](\"https:\/\/i.cbc.ca\/1.4279121.1504802922!\/fileImage\/httpImage\/image.jpg_gen\/derivatives\/original_620\/mosquitos-lab-5.jpg\")
<\/p>\n
Most of the mosquitoes they’re finding in Southern California are of the common Culex variety, which don’t transmit diseases. But disease-carrying Aedes aegypti and Aedes albopictus are spreading north and increasing their range. (Kim Brunhuber\/CBC)<\/p>\n
The mosquito, which can also transmit dengue, yellow fever and other diseases,\u00a0has been working its way north. And this summer, for the first time ever, it was spotted in this city only 40 kilometres\u00a0from Los Angeles.<\/p>\n
One was found in Luz Rosales’s Long Beach backyard. The yard is littered with toys, tarps covering furniture, and odds-and-ends, all of which can hold enough water to allow the mosquito to breed. The news that her house might be sheltering this dangerous insect, Rosales\u00a0says, was a shock.<\/p>\n
\n“I have a friend who’s pregnant,” Rosales says.\u00a0“I’m worried about her.”<\/p>\n
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- Zika virus: modified mosquitoes, bacteria use encouraged by WHO<\/a><\/li>\n<\/ul>\n\n
She needn’t worry too much about Zika, not yet. Cases\u00a0in the U.S. are way down, according to Dr. Henry Walke, chief of the Bacterial Special Pathogens Branch at the U.S. Centers\u00a0for Disease Control.<\/p>\n
\n“There is only one case,” Walke says.\u00a0“And \u2026 at this time last year, we were seeing a significant number of local transmission cases.”<\/p>\n
For reasons scientists still can’t explain, the spread of the disease has seemingly slowed worldwide. But\u00a0experts warn that ignoring the mosquitoes that can transmit Zika\u00a0would be a big mistake, because Aedes aegypti is slowly spreading across the country. This year, according to the CDC, the number of U.S. counties reporting the mosquito has increased by 21 per cent.<\/p>\n
\n\n![\"Steve](\"https:\/\/i.cbc.ca\/1.4279133.1504803079!\/fileImage\/httpImage\/image.jpg_gen\/derivatives\/original_620\/steve-mulligan-1.jpg\")
<\/p>\nSteve Mulligan, who heads Fresno County’s mosquito control program, checks a trap. He says it’s too early to tell if the Wolbachia bacteria spread through males is having an effect on the biting female mosquito population. (Kim Brunhuber\/CBC)<\/p>\n
Which brings us back to that mosquito truck. The technology used by the Debug Fresno program was designed by Verily, a Silicon Valley company owned by Alphabet Inc, Google’s\u00a0parent company.<\/p>\n
\nSteve Mulligan, who oversees mosquito control in Fresno County, says\u00a0the mosquitoes being spread were infected by bacteria called\u00a0Wolbachia. It’s naturally occurring in many mosquitoes, but if transmitted to Aedes\u00a0aegypti, it interrupts the females’ reproductive cycle. All the infected mosquitoes being released are non-biting males.<\/p>\n
\n\n“They have a job to do,” Mulligan says,\u00a0“and that job is to seek out and find all of these local females so that the eggs are infertile and no offspring are produced. And so as we continue this program we’ll see fewer and fewer of these local mosquitoes.”<\/p>\n
\n\nTo determine\u00a0whether it’s effective at reducing the Aedes\u00a0aegypti population, they’ve set\u00a0up traps across the area where the males have been released.<\/p>\n
Mulligan checks one trap the size of\u00a0a small flower pot.<\/p>\n
\n“Any small container that holds water can be attractive and serve as a source for this mosquito to lay her eggs and for her young to develop,” Mulligan says.\u00a0<\/p>\n
\n![\"Mosquitos](\"https:\/\/i.cbc.ca\/1.4279106.1504802694!\/fileImage\/httpImage\/image.jpg_gen\/derivatives\/original_620\/mosquitos-lab-7.jpg\")
<\/p>\nBrittany Deegan sifts through the mosquitoes that have been trapped, trying to find any Aedes aegypti. (Kim Brunhuber\/CBC)<\/p>\n
Then they\u00a0transport\u00a0their catch to the lab and count the mosquitoes\u00a0to see if the\u00a0species they’re targeting\u00a0is actually declining.<\/p>\n
Brittany Deegan\u00a0dumps a bunch of mosquitoes onto a petri\u00a0dish, teases and separates each mosquito with her forceps, then peers at them through a microscope.<\/p>\n
\n“We’re looking for the Aedes aegypti,” she says, “we separate the male and female, and we count them.”<\/p>\n
Other mosquito-release programs exist, but most involve genetically altering the mosquitoes with a gene that causes the offspring to die. Verily’s program involves\u00a0automated mass rearing and sex-sorting to allow them to release so many males into the targeted neighbourhoods.<\/p>\n
Already those with Debug Fresno\u00a0say they’re fielding calls from around the world, including Canada.<\/p>\n
Fiona Hunter, an entomologist at\u00a0Brock\u00a0University in St. Catharines, Ont., has found that for the past two years, mosquitoes that can carry\u00a0Zika\u00a0have been found in Ontario.<\/p>\n
“If you had asked me whether these (Aedes)\u00a0albopictus\u00a0and\u00a0aegypti\u00a0would establish in Canada even five years ago, I would have laughed at you,” Hunter says.<\/p>\n
“We are hoping that they don’t become established populations and therefore we don’t have to have this discussion of whether we would use the Debug Fresno model.”<\/p>\n
Hunter doubts this is the most effective way to control them, because while releasing millions of infected males every year could work, it’s\u00a0expensive.<\/p>\n
“It’s a great business model to have to continuously release infected males to bring down the populations,” Hunter says. “But whether or not society wants to absorb those costs, that’s another issue.”<\/p>\n
![\"Mosquito](\"https:\/\/i.cbc.ca\/1.4279115.1504802854!\/fileImage\/httpImage\/image.jpg_gen\/derivatives\/original_620\/mosquito-trap.jpg\")
<\/p>\nAedes aegypti’s preferred habitat is near humans, and only needs a cap-full of water in which to lay eggs. (Kim Brunhuber\/CBC)<\/p>\n
Debug Fresno is still in its pilot stage, and researchers say it’s still too early to tell if the program is paying off. Anecdotally, there certainly seem to be more mosquitoes in the air. Mulligan says even though the males don’t bite, they’re attracted to humans, because that’s where they expect to find females.<\/p>\n
Bonnie Smith says she doesn’t mind being a tasty guinea pig.<\/p>\n
\n“It’s kind of interesting to find out how it’s going to work and ultimately reduce the mosquito population,” Smith says.<\/p>\n
\nSo\u00a0when that van comes around, she’s actually happy to see it. More mosquitoes, she says: just what they\u00a0need.<\/p>\n