Take on the sick seat mate

Is there anything worse than getting onto a flight and the lady next you tells you she's nauseous and will likely throw up? I'm not neurotic but the thought of being in a confined space with somebody likely suffering from Ebola is not my definition of fun.
Then again, she may have just had too much to drink or ate some bad soup but if she coughs my way, I may push her out the emergency exit, you know, for the safety of everybody