Mosquito Repellent

Why You Should Use Mosquito Repellent

Insect repellent helps reduce your exposure to mosquito bites that may carry West Nile virus or other diseases, and allows you to continue to play, work, and enjoy the outdoors with a lower risk of disease.

When You Should Use Mosquito Repellent

Use repellent when you go outdoors. You should use repellent even if you're only going outside for a few minutes- it only takes one bite to get West Nile virus. Many of the mosquitoes that carry the West Nile virus bite between dusk and dawn. If you're outside during these hours pay special attention to using repellent.

How Often Should You Re-Apply Repellents

Follow the directions on the product you are using. Sweating or getting wet may mean that you need to re-apply more frequently.

What Percentage of Active Ingredient in a Product Relates to Protection Time

In general, the more active ingredient (higher percentage) it has, the longer a repellent will protect you from mosquitoes. For example, DEET products are available in many formulations - something with 30% DEET will protect you longer than one with 5% DEET. You cannot directly compare the percentage of one active ingredient to another, however.

Use your common sense. Re-apply repellent if you start to get bitten and follow the label instructions.

As a “rule of thumb”:
  • For many hours outside (over 3-4 hours) and/or where biting is very intense - look for a repellent containing more than 20% DEET. Products with more than 50% DEET do not offer additional protection.
  • For shorter periods of time, repellents containing less than 20% DEET, the repellent currently available with 7% picaridin or one of the products containing oil of lemon eucalyptus may provide adequate protection. There are other products available, but they may not protect as long as those named here.
  • Even if you’re going out for 10 minutes use a repellent - that’s long enough to get bitten!
Hint: Applying permethrin to your clothing ahead of time will give you even greater protection.

Remember—if you’re getting bitten, do something about it!

Choose a repellent that you will use consistently. Also, choose a product that will provide sufficient protection for the amount of time that you will be spending outdoors. Product labels often indicate the length of time that you can expect protection from a product. If you are concerned about using insect repellent, consult your health care provider for advice.

The National Pesticide Information Center (NPIC) can also provide information through a toll-free number, 1 (800) 858-7378.


Center for Disease Control and Prevention (CDC): The CDC is a source of information on disease control, and their Internet website includes a listing of state health departments. Call (972) 221-6400.