Third Batch of Mosquitoes Tests Positive for WNV in Antioch
Test Results show Sustained Transmission of Disease
Health Department Steps Up Effort Against WNV by Spraying Section of Antioch
NASHVILLE, Tenn., August 15, 2008 – Mosquitoes tested positive for a third time in the past month near the intersection of Murfreesboro Road and Bell Road in Antioch. Test results confirm sustained West Nile virus infection among mosquitoes.
“Having repeated positive mosquitoes over a period of time in one residential area is very rare in Davidson County” said Bill Paul, M.D., Director of Health. “We need to take additional, targeted action because these conditions represent a significant public health threat.”
Spraying will take place on Monday, August 18th and again Thursday, August 21st. Spraying will occur in selected areas within the following boundaries:
South of Nashboro Boulevard/Smith Springs Road
West of Owendale Drive/Butler Road
North of Anderson Road/Bell Road
East of Murfreesboro Road
Spraying will begin at dusk (8 p.m.) and nighttime hours when female Culex mosquitoes are most active.
If it rains, or winds are greater than 10 miles per hour, then the Health Department will reschedule spraying.
The Health Department will utilize ultra low volume (ULV) application of sumithrin/piperonyl butoxide (Anvil 2+2) by licensed technicians on trucks to control adult mosquitoes. Anvil 2+2 is registered by the Environmental Protection Agency for use in residential and recreational areas.
The first batch of mosquitoes tested positive for West Nile virus in Antioch July 17th. The Health Department increased trapping and testing efforts in the area to determine if there was sustained transmission of infection or if this was an isolated occurrence, and also stepped up efforts to remove standing water, apply larvicides, and notify residents to avoid mosquito bites. Despite these actions, a second batch of mosquitoes tested positive July 31, and a third batch collected last week tested positive, documenting sustained transmission of the virus in this area.
This is the first time since 2006 that the Health Department will spray to reduce the threat of WNV in the mosquito population.
Health Department officials continue to monitor standing water areas and apply larvicide when mosquito larvae are present. Mosquito traps are monitored twice weekly in all areas within Davidson County.
The Health Department will use several modes of communication to notify community members of when and where spraying will occur.
Spray Notification:
• Distribution of news releases and map of specific boundaries to Nashville news media.
• Spray notification announcement with maps placed on the Health Department’s website. (www.health.nashville.gov)
• Spray notification details placed on Health Department telephone hotline (340-5668).
• Signs placed 48 hours in advance at spray boundary entries notifying residents of spraying in English and Spanish.
• Use of Reverse 911 technology to send spray notification details to all households within the planned spray area with a telephone.
• Inform those who have submitted cell phone numbers to the Health Department.
• Spray notification maps and details placed on Metro 3 (Cable channel 3).
• E-mail spray notification specifics with maps to Mayor’s office and Mayor’s Office of Neighborhoods.
• E-mail spray notification specifics and maps to Metro Council Members.
• E-mail spray notification specifics to Health Department “Health E-Mail” Subscribers.
• Health Department staff drive through each neighborhood within the boundaries two hours leading up to spraying to inform those outside that spraying will occur.
• Each spray team is made up of a two vehicles:
o The lead vehicle is in place to provide any last minute notification to drivers or anyone outside that the spray truck is in operation. (When necessary, the person in the lead vehicle will radio to alert the person in the spray vehicle to turn off the spray unit before exposure occurs.)
o The second vehicle in the caravan is the truck with the spray unit. Each spray truck is equipped with yellow flashing lights. It is important to know the spray unit sounds similar to a chainsaw and that the compressor continues to operate even when the spray has been turned off.
The pesticide, Anvil 2+2 has been used for many years for mosquito control in residential areas. It will be applied in accordance with the EPA label and state regulations. The ultra-low-volume (ULV) spray applies approximately 3 ounces of compound per acre of land. Individuals who wish to reduce their exposure may take the following steps:
• Remain indoors during and 30 minutes after spraying occurs.
• Close windows and doors in your home during the spraying process.
• Do not allow children or pets to follow the Mosquito Control truck while spray unit is engaged.
• Make yourself as visible as possible if you are outside when the trucks are in your area.
• Make sure pets are indoors or out of the front yard during the spraying process.
West Nile virus is transmitted to humans by mosquitoes carrying the virus. Human cases of the virus have been rare in Davidson County, with five cases and one death. The Health Department recommends that everyone take steps to protect from mosquito bites:
• Limit time outdoors at dusk and nighttime hours when mosquitoes are most active.
• If you must be outdoors then wear a CDC recommended mosquito repellent that contains either Picaridin, Oil of Lemon Eucalyptus, or N-N-diethyl-meta-toluamide (DEET).
• Wear shoes, socks, long sleeve shirts and pants when outdoors during dusk and dawn when mosquitoes are most prevalent. Clothing should be light colored and made of tightly woven materials to keep mosquitoes away from the skin. Pant legs should be tucked into shoes or socks, and collars should be buttoned. Light colored clothes are less attractive to mosquitoes.
• Make sure all your windows and doors have screens and are in good repair.
Spraying and larviciding will not fully eliminate the presence of mosquitoes. The health department stresses taking the necessary measures to reduce mosquitoes in your neighborhood:
• Reduce or eliminate all standing water in your yard – especially in children’s toys, bird baths, clogged gutters, tires, flowerpots, trashcans, and wheelbarrows.
• Aerate ornamental pools or stock them with Gambusia fish.
• Apply mosquito dunks in standing water areas on your property.
• Cut back overgrown vegetation (mosquito hiding areas).
The Metro Public Health Department has a mosquito control information hotline with a recorded message about mosquito control efforts in Davidson County – 340-5668.