The winter deluge that pummeled Southern California this year, via multiple severe storms, gave Angelenos a reprieve from the drought, green lawns and a flower super bloom.
But a more ominous consequence looms has the weather warms up — mosquitoes.
Because of all the rain, which caused pools of water to be scattered across the Southland, public health officials are anticipating a “heavy” mosquito season and, with it, the threat of illness from the viruses the pests carry, including West Nile. So as peak mosquito season approaches in Los Angeles and across the region, officials say, residents need to be informed, do their part to lower the mosquito population and protect themselves from getting bit.
“All Los Angeles County residents play an important role in protecting their community,” the Greater Los Angeles County Vector Control District website says. “Mosquito control is a shared responsibility and residents can take simple steps to reduce them in their neighborhood.”
The Greater Los Angeles County Vector Control District serves 36 cities and portions of unincorporated areas.
Although mosquitoes can be a pest year-round, peak season is from early as May to September because of the warm weather, said vector control spokesperson Caroline Gongora.
Mosquitoes are vectors — meaning they are capable of transmitting diseases and can be considered a public health nuisance.
One disease that residents in the LA area should be wary of is the West Nile virus.
West Nile virus is the most common mosquito-borne disease that affects residents in Los Angeles County. Because West Nile is endemic in the county and found in city environments, public health agencies across the county detect it every year.
One in five persons infected with West Nile virus will exhibit symptoms, including fever, headache, body aches, nausea and a skin rash. These symptoms can last for several weeks to months. Vulnerable people can also be at risk of death.
“The heavy rain we received earlier this year may affect West Nile virus activity in Los Angeles County,” Gongora said, “but it more so depends on the transmission in the wild bird population.”
The first sign of West Nile virus activity is when dead birds — the proverbial canary in the vector coal mine — or mosquitoes from traps test positive for the disease.
“Dead birds serve as a surveillance and early warning system for West Nile virus activity,” Gongora said. “Birds such as American Crows, Common Ravens and California Scrub jays have a particularly high mortality rate due to infection.”
It is recommended that people do not touch dead birds when they are found. Instead, officials say, folks, should call local vector control.
If moving or discarding a carcass is necessary, the district urges residents to wear rubber or latex gloves. If gloves are not available, use a plastic bag turned inside-out over the hand and invert the bag to surround the bird, seal and discard it in the trash, if the bird will not be picked up for testing.
Taking precautions is particularly necessary during peak mosquito season.
In 2022, for example, the Los Angeles County of Department of Public Health reported 64 human cases of West Nile.
The total number of positive mosquito samples countywide was 357, and the total number of positive dead birds was 27.
In Long Beach, which has its own health department, four human cases West Nile cases were confirmed. The San Gabriel Valley Mosquito and Vector Control District reported 165 positive cases of West Nile virus in mosquito samples in 2022, and 11 of West Nile Virus-positive dead birds.
But health officials throughout LA County and beyond work year-round to help control and monitor the mosquito population.
In Long Beach, for example, the Bureau of Environmental Health has mosquito surveillance strategies, with staff monitoring potential breeding sites for mosquito habitation. Avian testing is done to detect the transmission of the virus in bird populations by having four chicken coops throughout the city. The blood of these “sentinel chickens,” as they are called, is tested every two weeks.
The LA County’s vector control, as well as San Gabriel Valley’s, use higher-than-average daily temperatures, mosquito population monitoring, mosquito testing for diseases, dead birds to assess health risks in communities.
They also use sentinel chickens.
Residents, though, can also do their part to prevent an invasive mosquito season hindering their spring and summer activities.
“After all the rain we received,” Gongora said, “residents should inspect their property for any standing water.”
This includes eliminating standing water in clogged rain gutters, rain barrels, discarded tires, buckets, watering troughs or anything that holds water. And change the water in pet dishes, birdbaths and other small containers weekly.
Residents should also take precautions to avoid bites by wearing loose-fitting long sleeves and pants, and using insect repellent when outdoors.
Officials recommend looking for repellents that include one of these four ingredients: DEET, Picaridin, IR 3535 or oil of lemon eucalyptus.
Vector control programs also offer free mosquito fish to residents with artificial lakes and industrial ponds. Mosquito fish feed on larvae — making them a great way to protect homes from mosquitoes. The use of mosquito fish should be paired with a weekly habit of removing stagnant water sources around the home, according to county vector control.
Although vector control programs work year-round to monitor mosquito and disease activity — and keep the public safe — they are also putting extra efforts to prepare cities and residents before peak mosquito season this year.
“We will continue to control mosquitoes in public spaces like street gutters, flood control channels, underground storm drains, and abandoned or unmaintained swimming pools,” Gongora said. “We will increase our public information efforts to educate the public on how they can prevent mosquito breeding and bites.”
To make a service request to the Greater Los Angeles County Vector Control District visit glamosquito.org, or call 562-944-9656.
Long Beach residents can report mosquitoes online at longbeach.gov or by phone at 562-570-4132, and report dead birds online or call 877-968-2473. San Gabriel Valley area and Pasadena residents can submit a tip at sgvmosquito.org or call 626-814-9466.