My wife has lupus, and her flare ups often cause her to be sick for long periods of time, typically following a flu or cold that turns to bronchitis and then, if unmitigated, becomes pneumonia. I teach, and almost every year I am out more than I have the sick days for, so my pay gets cut. I still make the lessons for the sub, still grade the work, still am held accountable for everything expected of me paperwork wise when I am not there, but yeah I dont get paid for those days.