A group of mosquitoes collected from San Onofre tested positive for the West Nile Virus, a potentially deadly disease.
This is the first positive test for West Nile all year, according to a County Vector Control statement Thursday.
Mosquitoes often do not travel far from the sight of the infection, so residents of San Diego should be aware of the disease, said Chris Conlan a county vector ecologist.
Conlan said that people should always be wary of mosquito bites, but with the recent detection of the virus, they should take extra measures to ward off the bugs.
Mosquitoes are most active between dusk and dawn, so the CVC says to stay inside during those times, or wear long sleeves and pants with bug spray containing DEET, Picaridin, or Eucalyptus.