Adele’s debut at the Grammy’s was a success. She performed beautifully after her vocal surgery (hemorrhaged polyp was removed). http://huff.to/wZBEQH
After following the advice of doctor’s and having the polyp removed, she strictly abided by not speaking for weeks. Not speaking or singing is very hard to do, but essential to vocal repair for a singer. She will be carefully followed by her voice teacher to ensure her healthy singing voice. http://www.usatoday.com/life/music/awards/grammys/story/2012-02-09/adele-throat-surgery/53033638/1
Everyone’s voice can withstand different levels of singing activity. To maximize that activity, secure and healthy technique is essential. So is a healthy lifestyle including adequate sleep, hydration, good diet and moderate exercise. http://www.healthyandconfidentsingingvoice.blogspot.com/2011/05/healthy-voice-and-healthy-you.html
Pay attention to your body and what it is saying. Even when you are down and out with a cold virus, the best thing you can do is to sleep and not speak. Whispering causes more wear and tear on the vocal folds than speaking alone, so stay quiet and find a notepad or apps on your phone. Unless there is absolutely no way out of it, if it hurts or feels weird when you sing, DON’T DO IT. Give it a rest and if it persists, get a professional opinion (voice professional or medical professional). Better safe than sorry as they say!