To use sprays effectively to eliminate all traces of bed bugs, you need to know the signs of a bed bug infestation. The first sign that you may have bedbugs are some itchy bite marks on your skin when you wake up in the morning. Dr. Carol DerSarkissian on WebMD says that the bites from bed bugs cause red itchy bumps on the skin.3 You can learn about their other signs and symptoms in my articles on what do bed bug bites look like.

It is hard to tell if you’ve been bitten by a bed bug unless you find bed bugs or signs of infestation. When bed bugs bite, they inject an anesthetic and an anticoagulant that prevents a person from realizing they are being bitten. Most people do not realize they have been bitten until bite marks appear anywhere from one to several days after the initial bite. The bite marks are similar to that of a mosquito or a flea — a slightly swollen and red area that may itch and be irritating. The bite marks may be random or appear in a straight line. Other symptoms of bed bug bites include insomnia, anxiety, and skin problems that arise from profuse scratching of the bites.
Wash the bites with soap and water. Wash the area with mild soap and water; use a bar of soap and enough water to wet surface of your hands. Work the soap in your hands into thick, soapy lather. Rub the lather over the affected area liberally. Repeat until the entire area is covered. Leave on and do not rinse. Allow the soap lather to dry over the bitten areas. You should experience immediate relief from itching.[5] 

Other types of bed bug traps include those that do not rely on humans as bait, but instead use CO2and/or other attractants. CO2 is thus far the most powerful lure for bed bugs, as it is the primary cue they follow to locate hosts. Traps that issue CO2 for a period of time are more expensive than Climbup™ traps, but can effectively trap bed bugs when no host is present, such as in common areas, vacant homes or units, offices, schools, and theaters. Thus they can help confirm infestation and eradication.
Reactions to bed bug bites vary among individuals. Many persons show no signs of bites. Others don’t realize they’ve been bitten until redness and swelling appear around the bite, sometimes with intense itching. Some exhibit inflamed swollen spots that may occur in linear series or have a rash-like appearance. Such bite marks, when they appear, may not show for several days after the person is bitten.
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