Info!
House has taken over a clinic not far from the apartments. Safe to assume the staff were turned to zombies and vacated. It's fully equipped and fully functional at this time, with several exam rooms and a single operating room.
In addition to providing health care and terrible/sarcastic bedside manner, House is also conducting research on zombies. Claire Bennett is his unofficial assistant. Hopefully Cuddy will join him on the healthcare for the living side of things!