The first cases of West Nile Virus have been discovered in Shasta County, one in a dead bird and another in an infected mosquito.
The bird was found in Anderson and the mosquito was found in Redding.
Although mosquitoes do need standing water to breed, officials said that Shasta County's dry winter will not have much of an effect on the mosquito population.
Most local mosquitoes breed in agricultural and urban water sources like gutters, neglected pools and livestock troughs.
In addition, the heat could make West Nile more virulent as heat encourages the virus to multiply, which could lead to a more pervasive spread.
So far this year, over 500 cases of West Nile Virus have been reported, but most of those reports have come out of central and southern California.