For reducing the risk of WNV among people, at least four products (with various active ingredients) are available as EPA-registered insect repellents. The active ingredients include:
1) DEET (as chemical: N,N-diethyl-3-methlybenzamide or formerly known as N,N-diethyl-m-toluamide) represents an insect repellent that provides complete protection for the longest duration among the repellents available for mosquitoes (view research article at: http://content.nejm.org/cgi/content/full/347/1/13).
Repellents containing DEET are available as pump sprays, aerosols, lotions, creams, soaps, and sticks. You may use these products to repel other biting pests, such as biting midges (no-see-ums), ticks, fleas, horse flies, deer flies and chiggers. The DEET concentration in products may range from less than 10% to more than 30% (for example, the military uses up to 100%). Products with concentrations around 10% are effective for periods of about 2 hours whereas 30% concentrations provide protection for about 6 to 8 hours. As the DEET concentration increases, the duration of protection increases. However, the excessive application of products containing DEET (with the same concentration) does not increase the duration of protection.
Products containing DEET may occasionally create some health problems (skin reactions including rash, swelling, itching; and eye irritation). Frequent application or saturation may not be necessary. Even though the chances of experiencing adverse health effects from using DEET-containing repellents are low, EPA recommends the following precautions:
- Read and follow all instructions and precautions on the label before application
- Store out of the reach of children
- Do not allow children to apply DEET themselves
- Do not apply DEET-containing repellents to children 2 years old or younger
- Do not apply DEET directly to children; apply to your own hands first and then place this material on the child (Note: repellents used on children under the age of 5 should contain no more than 10% DEET and no more than 30% DEET for other children)
- When applying DEET, avoid the child's face and hands
- Do not use DEET-containing sunscreens
- Avoid prolonged and excessive use of DEET; use sparingly to cover exposed skin only (treating unexposed skin is not necessary)
- Do not apply repellents in enclosed areas; avoid breathing a repellent spray and do not use a spray near food
- Do not apply directly on your face, especially near the eyes, nose, or mouth; apply sparingly around the ears; if using a spray, apply on the hands first and then apply to the face
- Do not use DEET on skin that is damaged by sunburn, cuts, bruises, or skin conditions (such as psoriasis)
- Apply DEET to clothing; however, this product may damage some synthetic fabrics and plastics
- Wash treated skin and clothing with soap and water after returning indoors
- If you or a child experience an adverse reaction to a repellent containing DEET, stop use, wash the treated area immediately, and contact your medical care provider.
You may view information about DEET at: http://www.deet.com/.
2) Picaridin or KBR 3023 [2-(2-hydroxyethyl)-1-piperidinecarboxylic acid 1-methypropyl ester].
3) Oil of lemon eucalyptus (OLE) or PMD (para-menthane-3,8-diol).
4) IR 3535 [3-(N-butly-N-acetyl)-aminopropionic acid, ethyl ester].
You may view information about these active ingredients at: http://epa.gov/pesticides/insect/choose.htm.