This is a question that is actually quite difficult to answer. If asked, "Should one go to work when one is ill?", the response is likely to be, "It depends on how ill you are."
And surely that really is the question, how ill do you have to be before you should give work a miss, staying at home instead? How ill is ill?
How often have you woken in the morning feeling a little under the weather perhaps with a sniffle or a slight headache? Then upon getting up, a brisk shower and a cup of char you begin to feel better. Once you arrive to work and get stuck in you forget that for the first ten minutes of the day you were contemplating ringing your boss to make your excuses.
The above situations are the extremes. Easy decisions. Go and stay. But what about somewhere in between? What about when you have been sick in the night and feel a bit better in the morning but still not right? Typically you will have a busy day; a vital meeting that you feel you can't miss. Under these circumstances many people will probably get up and go to work and struggle through. Sometimes they will be fine and they will feel better or at least not worse. Otherwise they will need to leave that meeting before they are forced to throw up in the waste bin or worse.
What might be a little galling is that the person who struggles in with a sense of duty and an aversion to filling in back to work forms is often lambasted for bringing in their bugs, being the Typhoid Mary of the workplace and in the event of anyone else becoming unwell the blame will most definitely be placed on their shoulders.
Woken up ill? Stay warm and under that duvet.
(Cartoon - http://4.bp.blogspot.com/-rxEhBAcOMgU/T5pWNtnVwYI/AAAAAAAAAPI/qfmA52Su6f8/s1600/blob-ill-with-doctors-letter-clipart.gif)