On June 20, the St. Clair County Health Department reported finding West Nile Virus positive mosquitoes for the first time this season. WNV was first discovered in the United States in 1999, in infected birds and is transmitted to humans via the bite of the mosquitoes.
By the summer of 2001, WNV had spread from its origin in New York across the lower 48 states. SCC HD’s conclusion was not unexpected—finding WNV in mosquitoes is a common summertime occurrence in this region.
Fortunately, most people (eight out of 10) infected with WNV do not develop any symptoms. About one in five people who are infected with WNV develop a fever with other symptoms such as headache, body aches, joint pains, vomiting, diarrhea, or rash. Most people who develop this type of disease will recover completely, but fatigue and weakness can last for weeks to months.
About one in 150 people who are infected develop a severe illness affecting the central nervous system, such as encephalitis (inflammation of the brain) or meningitis (inflammation of the membranes that surround the brain and spinal cord).
Severe illness can occur in people of any age; however, people over 60 years of age are at greater risk, as well as people with certain medical conditions such as cancer, diabetes, hypertension, kidney disease, and individuals who have received organ transplants.
There are no vaccines to prevent, or medications to treat, WNV beyond managing the symptoms. The most effective way to avoid WNV disease is to prevent mosquito bites. Here are some additional tips to prevent WNV.
USE INSECT REPELLANT
Use an Environmental Protection Agency registered insect repellent with one of the following active ingredients. When used as directed, EPA-registered insect repellents are proven safe and effective (do not use insect repellent on babies younger than 2 months):
▪ Picaridin (known as KBR 3023 and icaridin outside the U.S.);
▪ 2-undecanone; and
▪ Oil of lemon eucalyptus or para-menthane-diol (do not use on children under 3 years old).
AVOID BEING OUTSIDE WHEN MOSQUITOES ARE MOST ACTIVE
▪ The times to avoid typically are dusk and dawn.
WEAR LONG-SLEEVED SHIRTS AND LONG PANTS
▪ Outer clothing items can be treated with permethrin or purchased already treated to further reduce bites; and
▪ Do not use permethrin products directly on the skin.
CONTROL MOSQUITOES both INSIDE AND OUTSIDE THE HOME
▪ Use screens on windows and doors;
▪ Use air conditioning when available; and
▪ Mosquitos lay eggs near water. Once a week, empty and scrub, turn over, cover, or throw out items that hold water (i.e. tires, buckets, planters, toys, kiddy pools, birdbaths, flowerpots, or trash containers).
The 375th Aerospace Medicine Squadron Public Health Flight is also conducting routine mosquito surveillance on SAFB this summer. For info, call 256-4986. People also can find out more about WNV at the Centers for Disease Control website, https://www.cdc.gov/westnile/index.html.