Residents of San Jose, California have been alerted to the presence of West Nile virus-positive mosquitoes in the city, specifically in ZIP codes 95110, 95112, and 95125. According to the County of Santa Clara Vector Control District (VCD), in an effort to prevent the disease from affecting human populations, the pests will be targeted for elimination on Monday, September 18, starting around 10 p.m., with the operation lasting approximately two to four hours.
ALERT! West Nile virus infected mosquitoes have been detected in a small portion of the county. An adult mosquito control treatment will take place in part of the 95110, 95112, and 95125 ZIP codes on Mon. 9/18, at 10PM & concluding a few hours later.https://t.co/lGgJVVqBRI. pic.twitter.com/ZsNqsLlihH
— County of Santa Clara Vector Control District (@SCCVCD) September 12, 2023
The Vector Control District's mosquito-management program mainly focuses on preventing mosquitoes from reaching the adult biting stage; to this end, they prioritize targeting immature stages of mosquitoes found in standing water. When a West Nile virus-carrying mosquito is detected, however, the District takes the additional step of conducting adult-mosquito-control treatments in the affected area. Prompt action is critical in order to prevent the public from being exposed to the potentially deadly virus and to ensure public health and safety. Reducing the adult mosquito population also decreases the risk of human infection of West Nile Virus, as adult mosquitoes are the primary carriers of the illness in humans.
A rise in West Nile virus cases is not uncommon during the summer and early fall months, as mosquitoes thrive in warm weather. The District has implemented a dedicated surveillance program to detect the presence of diseases like West Nile virus, St. Louis encephalitis, and western equine encephalitis, which are all transmitted via the bite of infected mosquitoes. Data collected through this surveillance program enables the District to predict locations with higher risks of disease-carrying mosquitoes, which helps to prevent outbreaks from spreading.
Truck-mounted adult-mosquito-control treatments have been regularly conducted by the District since 2003, effectively reducing West Nile virus-transmitting mosquito populations. The public is informed of these treatments through mailed postcards, AlertSCC, emails to registered voters in specific precincts, Nextdoor, and via social media platforms such as Facebook, Instagram, and Twitter.
While adult-mosquito-control treatments pose minimal risk to people, pets, animals, or the environment when applied by professional control specialists, individuals who prefer to take extra precautions may keep family members and pets inside during the treatment, with windows and doors shut. The pesticide used for the treatment quickly breaks down upon exposure to sunlight, ensuring that people are unlikely to breathe or touch any harmful residue.
To assist in preventing the spread of West Nile virus, the County of Santa Clara Vector Control District recommends that the public take steps to minimize the presence of mosquitoes on their property. This includes inspecting for standing water weekly, draining or turning over any containers holding water, cleaning items such as bird baths and pet bowls, clearing debris from rain gutters to allow water to flow, and ensuring window and door screens are in good condition.
The public is also advised to limit outdoor activities during dusk and dawn, when mosquitoes carrying the virus are most active. If spending time outdoors, it is suggested that individuals wear long-sleeve shirts and long pants, preferably light-colored, as mosquitoes are attracted to darker hues. The application of insect repellents containing ingredients such as DEET, IR3535, or oil of lemon eucalyptus is also recommended. The County of Santa Clara Vector Control District offers free assistance with mosquito control and other vectors for residents who may be experiencing mosquito-related problems or know of potential mosquito-breeding sources.
