Bed bugs move from an infested site to new places by means of furniture, bedding, baggage, boxes, and clothing. Bed bug infestations occur around or near areas where people sleep, rest, or sit for a significant period of time. Bed bugs have been reported in many types of places in the United States including: apartments, single family homes, hotels and motels, dorm rooms, shelters, nursing homes, hospitals, movie theaters, fire stations, schools, office buildings, and libraries. 

The Environmental Protection Agency (EPA) offers a few simple precautions that can help prevent a bed bug infestation (from EPA web page: Preventing bed bug infestations).

At home:

• Check secondhand furniture, beds, and couches for any signs of bed bug infestation before bringing them home. How to inspect for bedbugs is described below and in the inspection section.
• Use a protective cover that encases mattresses and box springs which eliminates many hiding spots. The light color of the encasement makes bed bugs easier to see. Be sure to purchase a high quality encasement that will resist tearing and check the encasements regularly for holes.
• Reduce clutter in your home to reduce hiding places for bed bugs.

When traveling:

• In hotel rooms, use luggage racks to hold your luggage when packing or unpacking rather than setting your luggage on the bed or floor.
• Check the mattress and headboard before sleeping.
• Upon returning home, unpack directly into a washing machine and inspect your luggage carefully.

Discarded couches, mattresses, beds and other furniture may be
infested and should be left alone. Photo courtesy of
http://seeclickfix.com

Additional tips on how to prevent spreading bed bugs from an infested location to new places:

CBS Chicago article and audio story (June 2011): Avoiding bedbugs when you’re on vacation

National Pest Management Association (NPMA)
   Video (2009): Locating and preventing bed bugs (how they spread, travel tips)
   Articles: Bed bug prevention (everyday tips, tips for the office, tips while shopping, tips for travelers, tips for college students)

University of Minnesota article: Prevention for travelers