BOSTON  As if all the double-parked moving vans, anxious parents and mountains of discarded furniture and trash are not enough to fray nerves on the day when thousands of college students move into their apartments here, city officials on Wednesday were up against a tiny problem that poses a huge threat.

Bedbugs.

The first of September is traditionally when leases start or expire for off-campus housing here, and students moving in often claim the couches, beds and other material left behind. But city officials would prefer they buy their own furniture.

“The problem that you have, some old furniture that has bedbugs in them and they get passed around to other apartments,” said Mayor Thomas M. Menino, who took a tour of a student building with multiple code violations Wednesday. “We’re discouraging the use of secondhand furniture.”

With heightened awareness  some might call it panic  over the biting bugs nationwide, city officials are trying to warn colleges and landlords more than ever about bedbugs, adding another issue to a time of year that causes the blood (bedbug food) of many to boil.