Several hospitals in the Boston area are modifying their visitation rules in response to the spread of H1N1 and seasonal flu in Massachusetts. For example, only people age 18 and older are permitted to visit patients at Winchester Hospital, Lawrence General Hospital, Lawrence Memorial Hospital in Medford, and Melrose-Wakefield Hospital. Anyone visiting an H1N1 patient at Lawrence General Hospital must wear a mask and should not wander around the hospital, said a hospital spokeswoman. Visitors at all the hospitals are asked to wash their hands or use hand sanitizer when entering and leaving a patient's room and cough or sneeze into the bend of their elbow.