The only way to face a phobia really is head on. Maybe try gradual exposure by, first of all, looking at pictures of sick people. Then watch videos where people are ill (some films may show people being sick, for instance, or you could watch hospital shows). Then meet up with someone who is not well. You could try and volunteer at a hopistal/ hospice reading to people who are sick and the general interaction with the people will make you see they are nothing to be afraid of. If you don't want to volunteer, then going to visit someone with a baby or very small children would be a good alternative, as they sick up quite a bit.
It is worth seeking medical advice and help if you have a major phobia, but for most people gradual exposure works. Just try and keep calm when around someone who is sick and take slow, deep breaths, whilst telling yourself there is nothing to be worried about as sickness is just part of life. Just keep repeating 'there is nothing to worry about' in your head and the message should sink in.
i don't now! visit them often