How do bed bugs protect themselves?

A bedbug protects itself from being attacked by a human in various ways. Firstly the bedbug can tell from the breath of the person when he or she is asleep, so the bedbug will usually wait until it detects a person who is asleep before coming out of its hiding place and crawling on to the person's skin to feed on his or her blood during the night.

Secondly immediately after crawling on to the person and before piercing their skin in order to insert the tiny tube through which the bedbug needs to extract the blood into its mouth, which is adapted for piercing and sucking, the bedbug first injects a chemical comprising a powerful anaestheticand a coagulant into the sleeping person's skin.

This anaesthetic effect protects the bedbug by numbing any feeling, so the sleeping person does not know nor react to the presence of the bedbug on their skin while it is feasting on their blood such as by scratching until the anaesthetic has worn off. This only happens after the bedbug has completed its meal and by then crawled back off the person and to its hiding place, and so it can no longer be harmed by the person scratching or swatting.

Secondly the coagulant makes the blood come out of the wound the bedbug has made in their skin nice and slowly. This protects the bedbug from being flooded with too much blood coming out too fast

The bedbug also protects itself by only coming out of its hiding place to have its meal when it is dark, as well as when detecting breath of somebody asleep so should the bed occupant wake up he will not be able to see the presence of bedbugs unless he or she turns on a light and so will most likely not realize there are bedbugs in the bed.

Another protection is that the bedbug remains somewhere during day times such as in a crevice or the fold of a mattress or a crevice or crack in the floor or wall or nearby furniture so its flat tiny body can not be readily seen by people during daylight.