The mosquitoes were found in Madera and Fresno County.
A team with the Consolidated Mosquito Abatement District is out checking traps after they found a mosquito called the Aedes Aegypti.
They say it can transfer deadly diseases like Dengue and Yellow Fever. It's a concerning development.
"This is a new species. It has never been found in this part of California before," said Steve Mulligan with the Consolidated Mosquito Abatement District.
While the team was checking traps they placed Thursday evening,
they came across a small pan of standing water in a neighbor's front yard -perfect breeding grounds.
"We were able to find a small tray that was here containing specifically the larvae we were looking for to try to determine if that specific mosquito was here," said Jodi Holeman with the Consolidated Mosquito Abatement District.
Right now, the abatement district is trying to figure out how wide of an area the mosquitoes span. They've increased the number of traps and started heavily spraying the locations they've been sighted in.
It's important not to leave standing water because it only takes five to seven days for the eggs to turn into an adult mosquito.
"Any containers that you do need that may hold water be sure that you empty them once a week, possibly more than once a week," said Mulligan.
The County Department of Public Health says not only are these mosquitoes aggressive biters during the day when the sun is up, but they like to bite indoors as well.
"So you have to make sure your window screens don't have any holes in them so those mosquitoes don't come inside," said David Luchini with the Fresno County Department of Public Health.
They say the best protection is to use mosquito repellent and really do your part to monitor your area for standing water.
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