Bed bugs are biting insects that feed on the blood of people while they sleep. Bed bug bites are often numerous on the skin. Bites are found mostly on parts of the body not covered when sleeping, such as arms, shoulders, back, stomach and legs. Symptoms caused by bed bug bites can vary from one person to another. The main symptoms are the following: red lumps similar to those caused by mosquito bites, itching that can at times be very intense and uncomfortable. The intensity of the itching is more pronounced early in the morning but subsides as the day progresses. Bed bugs do not transmit any illnesses to persons bitten.