An adult female Aedes aegypti mosquito is seen ready to bite a human. These mosquitoes bite day and night and are very prolific in Los Angeles County. (Image courtesy of the Centers for Disease Control)
With the exotic mosquito invading backyard corners, Los Angeles County can no longer keep pace just by using pesticides or releasing mosquito-eating fish into ponds and old ponds.
So the county’s pest control district is trying to send out squadrons of sterilized male mosquitoes that will mate with females in the wild, lay the eggs, and hopefully reduce the female population. Females are targeted because they bite humans for the protein they need to lay their eggs, while males don’t bite.
A new use of biological bug warfare begins on Thursday, May 16, when 60,000 irradiated men Temples of the Egyptians A species of mosquito is released every week in Sunland-Tujunga to find mates, said Susan Kluh, general manager of the Greater Los Angeles County Vector Control District.
Excretion of irradiated man Temples of the Egyptians Mosquitoes will continue weekly through November, Kluh said. The district, which contains six million people and covers most of Los Angeles, from Santa Clarita to the San Fernando Valley to San Pedro and the southeastern counties, is starting the program in Sunland-Tujunga because it will be less intrusive. Males in an area bordered by mountains to the north, he said.
Using sterilized males to depopulate the species is one tool in the district’s mosquito-killing toolbox, which also uses hormonal pesticides to disrupt the pest’s life cycle. But sterile mosquito technique is preferred.
“It is environmentally friendly. There are no other impacts,” Kluh said.
The vector control district is spending about $255,000 on the sterile release program this year, but that cost could increase, he said.
Here’s how it works:
In the wild, up to 10 sterile males will be released for each of them, greatly increasing the chances of mating with sterile mosquitoes. Females can lay up to 150 eggs, but eggs with sterile sperm will never hatch. Females die after about a week, and without new babies, the population declines, Kluh explained.
“And when the number Aedes “The female mosquitoes will come, people will go outside and not get bitten,” he said.
The mosquitoes are collected and the males are placed in a kind of X-ray machine that shoots them enough radiation to render them sterile – but not enough to reduce their overall fitness. Males are then placed in release cages that are manually opened in the areas.
LA County is the second in the state to use sterile mosquitoes to reduce the population Aedes. The first group to pioneer the practice was the West Valley Mosquito and Vector Control District, which continues to hold weekly releases in Ontario, Montclair, Upland, Rancho Cucamonga, Chino and Chino Hills, said Brian Reisinger, community outreach coordinator.
The goal is to reduce Aedes population now, before the peak mosquito season in July and August, Reisinger said.
In September 2023, pilot project results showed a 70% drop Aedes Residents in Ontario target neighborhoods, he said. This led to an extensive program in six cities that began in late April. “With this 70% reduction, we’re excited to see what happens this year,” he said.
Experts say that the population Aedes In Southern California, there has been a four- to ten-fold increase since 2017. Recent wet years, including unusual humidity and summer storms such as Hurricane Hillary in August 2023, have created excellent breeding grounds.
The Aedes Can do more than spoil a backyard barbecue. They carry worrisome diseases, including yellow fever, chikungunya, dengue fever and Zika. This exotic species of mosquito is mega unpleasant, it bites day and night. They are known as ankle bites and leave a lot of red, itchy welts each time.
Two cases of mosquito-borne dengue fever in humans last year – one Pasadena and one inside Smooth beach – were the first two cases ever reported in California that were not imported by someone who had traveled outside the US. The two diseases were locally transmitted by mosquitoes, Kluh said.
“Dengue is very painful. I heard it sounds like every bone in your body is broken,” he said. However, only 20% show symptoms. According to him, two people have fully recovered.
The vector control areas involved only the Culex species known as the southern house mosquito. They carry West Nile virus but are easier to contain. They lay their eggs in clusters in a trash can or cart filled with water and are destroyed when the container is overturned.
These common mosquitoes only bite at night, as opposed to a 24-hour biting cycle Aedes.
“These new, invasive species (mosquitoes) bite all day long. They follow you into your house — so you can have the same problem sitting on the couch,” Kluh said.
They lay durable eggs that can hatch after a year. Eggs stick to containers even after the water has been emptied – buckets, pots, troughs, birdbaths, even bottle caps – then they are transported to other places. Because they are so hardy, they have established well in Southern California, he said.
“In recent years, we have had a lot of problems with providing adequate control for this Aedes Mosquitoes,” Kluh said.
In the West Valley district, the sterile mosquito program is used alongside traditional control methods – for example, tree traps continue to be installed to identify hotspots in the district. They then apply spot treatments with pesticides to standing water or use bait to attract and kill mosquitoes, Reisinger explained.
“Having this new tool is great, but it’s not going to be a magic bullet,” he said.
The LA County District hopes to expand the Sunland-Tujunga program to other high-concentration areas. AedesClu said. “If the mosquito population (in Sunland-Tujunga) is very low throughout the summer, we’re hoping to get it to a larger population,” he said.
The county also works with the Orange County Mosquito and Vector Control District, sharing materials and equipment. The Orange County District is preparing a sterile release Aedes Mosquitoes in Mission Viejo, Kluh said.
While these biologics last, summer is coming. After a rainy winter and spring, experts expect all kinds of mosquitoes to be out in search of blood.
Tips for preventing bites and removing larvae and adults Aedes includes:
• When going outside, wear a mosquito repellent that contains DEET (15% is adequate); IR3535, picaridin or oil of lemon eucalyptus.
• Wear long pants and long sleeves.
• Empty and clean all sources of water collection, such as pots, birdbaths, litter boxes and gutters.
• Place mosquito fish in ponds, horseshoe pits and permanent water sources.