As mentioned earlier, applying insect repellent at bedtime will probably not deter bed bugs from biting. When working in severely infested dwellings, there may be some benefit to spraying tops and bottoms of shoes with DEET-based repellents. Those working in bed bug-infested environments may also want to hot wash or run clothing, etc. through a dryer upon returning home or to the office.
My husband returned from a Military Deployment…and brought bed bugs home with him. The day after we realized we had them, an exterminator that specializes in Bed Bugs came to our house and sprayed. They scheduled themselves to come back in 14 days to spray again (to kill the new bugs that hatch after the initial spray). We were old the spray would kill all the adults and babies…and the second spray would get the new hatchlings. 3 days after the initial spray, we started seeing adult bugs again!
All of the stages of bed bugs are visible, at least if you don't need reading glasses and you have a sufficient amount of light. So if you're looking closely enough, you can even see bugs in the nymphal first instar stage. A fecal spot, for its part, can be as large as a bed bug itself in terms of the area it covers. The spots are basically digested blood, so most are dark in color. On a white mattress, they stand out pretty well.
Don't assume your bites are bedbugs. Bites can be hard to identify, even for doctors. Rule out mosquitoes, fleas, mites, and biting gnats by conducting a visual inspection. It's best to collect and identify bedbugs to confirm bites. Look for the bugs themselves or their bloodstains, especially along the seams of mattresses. Further, look for dark spots of insect waste where bedbugs might crawl into hiding places on furniture, walls, and floors.
If, after everything is thoroughly taken apart and cleaned, you still have an infestation, other measures may need to be taken. If you have an infestation of bats, you may also have a serious infestation of “bat bugs” which are very similar to the common variety. Often, the infestation is not as strong as those caused by their cousins as they are more apt to wander and relocate.
Unlike those of other insects, bed bug bites may sometimes appear in tight lines of multiple, small, red marks where multiple bed bugs have fed along an exposed area. Bed bug bites can cause itchiness. Initially, a victim may detect a slight burning sensation. The burning area then develops red bumps, known as papules or wheals (rash). In extreme cases, bites may swell dramatically or turn into blister-like skin inflammations.