The Shelby County Health Department has received confirmation of mosquitoes carrying West Nile virus within several areas around the county.
The areas include 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 West Nile Virus pools on record in addition to the most positive pools present this early in Shelby County.
Since the middle of April, the SCHD 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 to reduce the number of adult mosquitoes.
As an additional precaution, the SCHD will continue to schedule truck-mounted sprayings (i.e. adulticiding) of EPA-approved insecticides in areas where adult mosquitoes are infected with WNV, weather permitting. Adulticiding is only effective at killing mosquitoes which are actively flying in the air when the spray is applied to a given area.
To ensure cases of human West Nile Virus are minimized, residents are also encouraged to be vigilant as it relates to controlling mosquito populations around their homes and businesses by taking the following precautions:
Humans contract West Nile Virus via a bite from an infected mosquito. Although the virus 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 and 2012 West Nile Virus reports can be found at http://shelbycountytn.gov/index.aspx?NID=2404.