Guide to Insect Repellents, Insecticides, and the Prevention of Insect-borne Diseases

Fleas, mosquitoes, lice, assassin bugs, sand flies, chiggers, ticks and other biting insects may be carriers of an infectious disease. With the advent of global warming, insects and insect-borne infectious diseases are spreading to new areas. To protect yourself against contracting an insect-borne infectious disease, the Centers for Disease Control and Prevention (CDC) recommends using the following insect repellents and insecticides; they have been shown to be safe and effective, even in pregnant and breastfeeding women. Clothing, tents, and mosquito netting are ideal for first order of protection and sleeping, especially when saturated with Permethrin (which kills insects on contact).

To protect against chiggers and ticks, wear light-colored or white long pants, long-sleeved shirts, and socks so ticks can be more easily seen; pull socks over pant cuffs. Wear a hat and place petroleum jelly around hairline to keep ticks from crawling into hair (where they will be very difficult to find). Do a thorough tick check each morning & evening before entering and leaving your tent.

The CDC does not recommend other insect repellents and products as they have not been shown to be effective despite manufacturers claims. These include natural plant oils, (such as citronella oil, cedar oil, geranium oil (or geraniol), and lemongrass oil), repellents containing vitamin B1 or garlic, and wristbands and ultrasonic devices.

Application

• Avoid spraying repellents on or near the face; instead spray on hands and then rub on face; avoid contact with the eyes and mouth.
• Parents should apply repellents and insecticides to children.
• Reapply regularly and if/when mosquitoes—or other insects—bite.
• Lower concentrations provide shorter protection.

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DEET

• 30% concentration should provide protection for 6 hours.
• 20%-23.8% concentration provides 4-5 hours of protection.
• 6.65%-10% concentration provides about 1-3 hours of protection.
• Concentrations over 50% offer no additional benefit.
• Controlled-release products might offer a longer duration of protection even with lower concentrations.
• Safe for children > 2 months in concentrations of 10%-30%.

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Picaridin

• 20% concentration provides protection for up to 7 hours.
• 10% products provide protection for up to 5 hours.
• Known as icaridin in Canada. Canada recommends against use in children under 6 months.

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IR3535

• 7.5% concentration provides about 10-60 minutes of protection.

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Lemon Eucalyptus Oil

• Protection for up to 2 hours.
• Not recommended for children < 3 years.

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Permethrin

• Kills insects on contact. Apply to clothing, gear, netting, & tents; it will last through numerous washings/rain storms. Do not use directly on skin.

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