The quaint bedtime saying "sleep tight, don't let the bed bugs bite" has become a grim mission statement for even the finest hotels in the United States amid a resurgence of the tiny bloodsucking pests. Rising complaints about these unwelcome guests that bite in the night are leading to red faces at reception desks and an increase in the number of help calls, according to pest control firms and entomologists. Hotels battling infestations typically request discreet and immediate service, and for good reason. Even though they don't pose a health threat, bed bugs, which live off human blood, can take...