Southern California lawns are expected to take a beating this summer, but at least that means less pesky mosquitoes likely will be about.
Rainfall can lead to stagnant water where mosquitoes breed as temperatures rise. And Southern California is in a drought, and this past winter and spring didn’t bring much rain, either.
But that doesn’t mean locals will be mosquito-free.
“Drier conditions may limit breeding areas but can concentrate mosquito activity around available water sources,” said Francis Delapaz, a spokesperson for San Bernardino’s Department of Public Health.
Besides irritating bites, mosquitoes can spread diseases such as West Nile virus, dengue, Zika, and malaria, said Brian Brannon, a spokesperson for the Orange County Mosquito and Vector Control District.
Generally, mosquito populations in Southern California peak from June until mid-October. Populations of the larger culex species have historically peaked in June while the numbers of the invasive aedes, or so-called ankle-biter species, pick up in August and September, he said.
So far this year there have been no reported human cases of West Nile virus and 33 reported travel-related cases of dengue in the state, according to California’s Department of Public Health: That includes five in L.A. County, one in Riverside County, and two in San Bernardino County.
Last year, there were 723 dengue cases in California, compared to 250 in 2023 — the vast majority were acquired while traveling.
The symptoms of dengue and West Nile virus can include a fever, headaches and joint pains, experts say, with each illness at times having other unique effects on the body. Both illnesses, in rare cases, can be very serious.
Residents are advised to regularly walk around their property and look for potential mosquito-breeding sites, from an unmaintained swimming pool to an upturned bottle cap. Mosquitoes, particularly the invasive, small ankle biters, don’t need much water to thrive.
“They are container breeders,” Steve Vetrone, an assistant general manager at the Greater Los Angeles Vector Control District, said about aedes mosquitoes. “Anything that can hold water, whether it’s plant saucers, rain barrels, a bucket left in your yard, water bottles left in your recycling bin.”
Long-sleeved shirts and pants, insect repellent and even spraying on oil of lemon eucalyptus are recommended by vector control experts.
Some vector control districts release sterile mosquitoes, to lowering the population of them and reduce disease transmission.
To learn more about mosquitoes in your area, visit the website of your local agency:
- Greater Los Angeles County Vector Control District
- Orange County Mosquito and Vector Control District
- Riverside County Vector Control
- San Bernardino County Mosquito and Vector Control