Anna asked:


Me and several of my flatmates have had quite bad headaches for the past few days. As far as I can tell, that is the only real symptom, but it seems strange that we would all get headaches at the same time. Can anyone suggest what the cause might be, and how best to treat it?
Carbon monoxide seems unlikely, as there’s been no changes in the system, and only a few of us are having headaches. There’s been no new painting either.

Wanda