West Nile Virus: Recommendations for outdoor activity

Farm Forum

With all the rain the mosquitoes are plentiful and will stay that way in the future. West Nile Virus (WNV) is in North America to stay and we must be as vigilant today as we were when the virus first appeared in South Dakota in 2000. SDSU Research has yielded valuable information about Culex tarsalis, the predominant mosquito that carries WNV virus in South Dakota:

1. It adapts to our weather extremes, thus surviving even in hot dry weather.

2. It is a “stealth” bitter, you could be bitten and not know it, unlike the bites from the usual mosquito.

3. South Dakota have developed excellent control programs, trapping, larvaciding, and adulticiding; but, it is OUR OWN responsibility to take precautions to protect ourselves.

4. Culex tarsalis numbers appear to be highest and most active in late evening (10 p.m. – 2 a.m.), but they can be out at anytime, thus precautions should be taken whenever outdoors.

CDC/NIOSH recommends the following for outdoor workers (and any time outdoors):

1. Use insect repellent if you work outdoors:

· Apply insect repellent containing DEET (more that 20% DEET for longer protection), picaridin, or oil of lemon eucalyptus to exposed skin and to clothing.

· Use permethrin on clothing only.

· Carefully follow label directions for repellent use.

· Do not apply pump or aerosol products directly to the face. Instead, spray these products onto the hands and carefully rub them over the face, avoiding the eyes and mouth.

· Use a repellent that provides protection for the amount of time that you will be outdoors and reapply it as needed. The percentage of active ingredient is the repellent determines the length of protection.

· Wash skin treated with insect repellent with soap and water after returning indoors.

2. Use protective clothing if you work outdoors during mosquito season:

· Wear long-sleeved shirts, long pants, and socks.

· Spray clothing with products containing DEET, picaridin, oil of lemon eucalyptus, or permethrin as mosquitos may penetrate thin clothing.

· Use permethrin repellents on clothing as directed; do not apply them directly to skin.

· Washing clothing treated with insect repellent before wearing it again.

· Do not apply repellent to skin that is covered by clothing.

3. Avoid handling dead animals when possible, if you must, take the following precautions:

· Use tools such as shovels to avoid direct contact with the animals.

· Wear examination gloves, such as nitrile or poly gloves that provide a protective barrier between your skin and the blood or body fluids.

· If gloves are not available, use a plastic bag, which may act as a protective barrier between the animal and your skin.

Places Where Mosquitoes May Breed – Keep Them Drained

· bird baths/ flower pot bases

· storm water drains

· landscaping

· roof gutters/eaves

· compost piles (turn frequently)

· ornamental ponds

· attic vents

· pool covers/ tarps

· wading pools

· trash cans/ yard equipment

· leaky faucets

· old tires