In response to elevated West Nile virus (WNV) threat in the San Fernando Valley, more steps were and are being taken by the Greater Los Angeles County Vector Control District (GLACVCD) to target and combat the virus-carrying mosquitoes.
GLACVCD spent the early morning hours of Wednesday, Sept. 27, spraying the non-residential Sepulveda Basin recreation area to try and rid it of adult mosquitoes that may carry the virus. The low-volume fogging was performed between 1 a.m. and 5 a.m.
“About three square miles of the recreation area were treated over several hours,” said Kelly Middleton, GLACVCD’s director of community affairs. She said the treatment would last for a couple hours, but it breaks down in sunlight.
“It only kills the mosquitoes out at the time of the treatment,” Middleton said.
Today, Sept. 28, GLACVCD officials will canvas neighborhoods in Encino, Northridge and Reseda to inform and warn residents about the elevated concerns the vector has for the potential for virus-carrying mosquitoes in those communities.
“We’ll have seven teams going out to areas where we see the increase in activity,” Middleton said, adding that the teams will hang informational placards on front door knobs and handles about West Nile Virus, along with tips and precautions residents should be taking.
“If people are home and have questions we will be happy to talk with them. But we will not be knocking on doors or doing inspections,” Middleton said.
“The point is to get the information that the WVN risk is higher in the Valley this year than in previous year. For our district (which covers 35 cities, including those in the San Fernando Valley) it’s a kind of a hot spot.”
Mosquito surveillance data shows the increased levels of WNV activity in the areas like the Valley, officials said. A dozen mosquito samples tested positive for WNV so far this year, and sentinel chickens confirmed virus activity.
In addition, the LA County Department of Public Health has confirmed multiple WNV human cases in the San Fernando Valley. At least 17 new WVN cases were reported in Los Angeles County, including three deaths among elderly patients who died due to neuro-invasive West Nile virus infection.
The total number of West Nile virus cases and deaths in Los Angeles County this year is 98 cases and six deaths.
To date, no Zika virus infections have been acquired locally in Los Angeles County. However, the Aedes mosquito that can carry and spread the Zika — which can cause birth defects, including brain malformations, in unborn children — is present in some areas of the county posing a risk that infection could occur here.
Since 2015, 116 infections, including 10 infections this year, have been reported among people traveling to those areas becoming infected and carrying the infection back to LA County.
Residents planning to spend time outdoors are being reminded of the importance of preventing mosquito bites and removing sources of standing water where mosquitoes lay eggs and develop.
“At this time of year mosquito bite prevention is most important,” said Levy Sun, vector public information officer.
“Getting sick or dying from mosquito-borne diseases is a real threat here in Los Angeles county. But there are steps people can take to stay healthy and reduce the risks,” Sun said.
“The solution is simple: use insect repellent, and tip and toss containers that can hold standing water.”
Infection with WNV is often mild, but the virus can cause significant cognitive and neurologic symptoms in some patients. Milder fever and body aches can progress to weakness, confusion, and paralysis that could take months to years of recovery, or even result in a patient’s death.
At present there is no cure or vaccine available for treatment.
Along with preventing mosquito bites, GLACVCD offers other tips:
— Apply mosquito repellents to exposed skin before going outdoors. Clothing can also be treated with permethrin products to prevent bites (read and follow all labels);
— Use and reapply repellents recommended on the label. How long a repellent works depends on the active ingredient and the concentration you select. The Centers for Disease Control (CDC) recommends products with the active ingredients DEET, Picaridin, IR3535, some oil of lemon eucalyptus and para-menthane-diol products as being safe and effective.
— Use infant seat /stroller screen covers on babies younger than two months, and only EPA registered repellents on children. Oil of lemon eucalyptus should not be used on children younger that three years of age.
Around the home, eliminating mosquitoes from properties is critical:
— Any water left standing for more than one week in containers such as flower pots, fountains and pet dishes provide the perfect breeding habitat for mosquitoes.
— Check water collected in rain barrels and buckets as these can breed hundreds of mosquitoes every week. If larvae is detected, treat immediately with BTI products or dump the water onto lawns where the immature mosquitoes will die (do not pour into gutters or streets). Discard or seal these containers against future mosquito problems.
— Ensure swimming pools, spas and ponds are properly maintained. Report inoperable pools to the GLACVCD at ReportMosquitoes.org, or by calling (562) 944-9656.