The Shelby County Health Department has received confirmation of mosquitoes carrying West Nile virus within the areas of Memphis (zip codes 38116, 38122, 38127), Bartlett (zip code 38133), Germantown (zip code 38125), Collierville (zip code 38017), and unincorporated Shelby County (zip code 38141).
This is the earliest occurrence of positive WNV pools on record in addition to the most positive pools present this early in Shelby County.
Since the middle of April, the Health Department's Vector Control Program has applied Environmental Protection Agency (EPA)-approved larvicides to bodies of water known to produce mosquitoes as part of its proactive effort to decrease the number of mosquitoes. Larviciding is the most effective method of reducing mosquito populations and will continue throughout the summer.
Health Department also will continue to schedule truck-mounted sprayings of EPA-approved insecticides in areas where adult mosquitoes are infected with the virus, weather permitting.
Residents are also encouraged to be vigilant as it relates to controlling mosquito populations around their homes and businesses by taking the following precautions:
· Wear DEET-containing mosquito repellants according to label directions.
· Eliminate standing water where mosquitoes can lay eggs. Check properties for objects – including old tires, flower pots and drip plates, tin cans, buckets, and children's toys – that collect rainwater and either drain or dispose of the water.
· Install or repair windows and door screens.
· Empty, clean and refill birdbaths and small wading pools weekly.
· Empty and refill pets' water bowls every few days.
· Repair failed septic systems.
· Repair leaky outside faucets.
· Clean rain gutters and down spouts.
· Secure swimming pool covers tightly and remove any standing water after rainfall.
· Store wheelbarrows, canoes and boats upside down.
· Stock ornamental lawn ponds with mosquito fish (Gambusia), which eat mosquito larvae. (Gambusia fish are available FREE from the Vector Control Program; call (901) 222-9715 for availability.
Humans contract WNV via a bite from an infected mosquito. Although WNV can occasionally cause severe disease, most human infections are mild, resulting in fever, headache and body aches lasting only a few days.
Symptoms of severe disease include a high fever, neck stiffness, stupor, disorientation, coma or convulsions. Persons over the age of 50, under the age of 5, and those with compromised immune systems are at higher risk of severe disease and should be especially careful to avoid mosquito bites.
"Historically, most human cases of West Nile virus in Shelby County have not occurred until the months of August and September," said Tyler Zerwekh, DrPh, REHS, administrator for Environmental Health Services Bureau at SCHD.
"It is however absolutely critical to exercise the recommendations listed above in addition to using mosquito repellants before going outside to work or play, especially during evening and nighttime hours, to help reduce the mosquito burden in Shelby County."
(A copy of the 2011 WNV report can be found at http://shelbycountytn.gov/index.aspx?NID=2404.)