Whether people are traveling or dealing with bed bugs in their home, one of the most common questions I receive is “can I use DEET-based mosquito repellent to keep bed bugs away from me while I sleep?” There are two ways to look at this question: do DEET sprays work and can I keep bed bugs away from me.
First let’s define repellency as it applies to bed bugs. Something being repellent means that insects can sense it and avoid it. Obviously DEET-based mosquito sprays are repellent to mosquitoes which is why people spray their clothes when heading outside during warmer months. Research has also shown that DEET-based insect sprays can also be repellent to bed bugs. The length of that repellency is directly dependent upon the percent of DEET in the spray. Meaning the higher percentage of DEET, the longer it will be repellent. What most people don’t understand is that just because something is repellent, it doesn’t mean bed bugs won’t feed on you. It just means they are less likely to, and research has shown the repellency of these products breaks down quickly.
In fact, many over-the-counter (OTC) pesticides have a level of repellency associated with them. Meaning that bed bugs and other insects can often sense the presence of pesticides and avoid the surface they are sprayed on. Research has shown that bed bugs will avoid surfaces sprayed with certain pesticides proving that pesticides can be repellent to bed bugs. What the research also demonstrated though was that the attraction of food and other pheromones will overcome the repellency of those pesticides. This means that if bed bugs are hungry they will cross surfaces treated with the pesticide to get to the food.
The take home with this information is that you can’t spray your clothes with DEET or spray a circle around your bed with a pesticide and be assured you’ll keep bed bugs away. It’s not to say using DEET consistent with the label won’t reduce the chance bed bugs feed on you as long as it’s active. However, it breaks down quickly, and bed bugs may choose to “ignore” the spray and feed anyway. What people also lose sight of is that DEET is a synthetically derived product and following label directions is important. Using a product against the directions and extended exposure to these products (such as sleeping every night in sheets sprayed with DEET) can have negative health effects.
The other aspect to the over-application of pesticides or sprays that have a repellent component is that you can change the way a bed bug infestation behaves. While bed bugs will cross repellent surfaces to feed, if a large portion of surfaces in a home have been treated with a repellent product the bugs will hide in places you wouldn’t expect and you can spread them throughout your home. Bed bugs behaving in a normal fashion can make treating them much easier because knowledgeable professionals know approximately where they will be hiding. The concept is similar to a strategic sneak-attack. Catch your enemy off-guard as they are going about their predictable, daily routines.
A more logical use for a DEET-based product would be entering an area you think may have bed bugs in it and applying it to your shoes to reduce the chance you take bugs home with you. If label permits, applying a repellent spray to a bag you’re taking into an environment for a short amount of time you think may have bed bugs to keep bed bugs off of it. Remember though that the spray may only last for a few hours so this may not work for suitcases and traveling for long periods of time as the spray will break down quickly. You also want to consider how much contact you will be making with that bag as if you applied a repellent to a purse that was resting against your body all day there could be health risk associated with that exposure.
So in conclusion, DEET-based insect repellents can help with keeping bed bugs away for short amounts of time but nothing is fool-proof. The most important aspect is to follow label directions with these products as they are often used in manners that are inconsistent with their label directions. Lastly, using these products inconsistent with label directions and the over-application of repellents or pesticides can have a negative impact on both the bed bug infestation within a home as well as your health.