In your luggage. Bed bugs live in the creases and folds of bedding, furniture, and baseboards. They feed at night while you sleep. Look for rust-colored spots on bedding or furniture. The bugs look like apple seeds. Keep your luggage on racks or in the bathtub away from their hiding spaces. When you get home keep your luggage outside and put all your clothing into the dryer (120 f) for 15+ min to kill bugs & eggs.
Cimex lectularius or. The bed bug is a parasite that is nocturnal. It can be transported on your clothing, luggage, second hand furniture etc. You can even get it using public transportation. It can go up to a year without feeding, so that allows it to just sit and wait until it catches a ride on something or someone. If you live in an apartment complex it may move from one unit to another. It is an insidious problem.