Summer is the season that brings us outdoors to enjoy picnics, barbecues and campfires. Unfortunately, blood-feeding arthropods such as mosquitoes and ticks can ruin our outdoor experiences by making us itch or by spreading disease. Over-the-counter sprays are one way that people avoid a forced retreat to the indoors. Choosing the right product and understanding how it works is important to keep you and your family safe. Here are a few considerations.
Repellant vs. Pesticide. There are two classes of products that you might see on the shelf. Products that contain DEET, picaridin, oil of lemon eucalyptus and IR3535 are repellants. These products interfere with the host-finding abilities of biting insects, making you hard to find. On the other hand, products that contain permethrin are pesticides that kill these organisms on contact. Permethrin is used to treat clothing, hats, shoes, and gear (backpacks, tents, etc.), and should never be applied to the skin for safety reasons.
Repellant Formulation. Repellants differ in their effectiveness at keeping pests away. On the bottle is a “percent active ingredient” listing, which is a measure of how long the product will remain effective. The higher the percentages, the longer it lasts. In general, products with less than 10% active ingredient provide only limited protection (1-2 hours at most). Here are some specifics about two of the common active ingredients.
- DEET comes in concentrations from 4 to 100%. Despite this broad range, studies have shown that concentrations over 50% do not provide any additional protection. Therefore, products with 20 to 30% DEET are recommended for outdoor exposure of four to five hours.
- Picaridin concentrations range from 7 to 20%, with a 20% concentration providing four to five hours of protection (equivalent to DEET at the same concentration).
How to Apply. For repellents, use just enough product to cover exposed skin and clothing – do not over-apply. Never directly spray your face, but rather spray your hands and apply to areas as needed. Follow label instructions carefully for applications, especially for children.
Treatments using permethrin to protect clothing should be done outdoors in an area with limited wind. Treat materials according to the label, paying particular attention to the amount of time needed for the product to dry. In most cases, once the material is dry, it is safe to wear. Additional information can be found on the TickEncounter website, including information about having your clothing professionally treated.
Clean Up. After outdoor exposure, a shower is recommended to remove repellants applied to skin. This should be followed by a tick check. See TickEncounter’s Shower Cards for more information.
Other Options. Screenhouses and appropriate clothing, such a long pants, long-sleeved shirts and a hat can be utilized to reduce problems with biting insects. Visit the following links for information on managing mosquitoes and ticks in your yard.