Hate to hear of anyone who may have the Swine flu... that is a pretty dramatic & dubious excuse to not follow through w/a contract. You just never know... if he does have the S.Flu, he could die. If he is making excuses, he could drag that ordeal on & on...
I say there is more fish in the sea. Maybe tell him you will pray he gets better, but you must move on due to your circumstances... perhaps an altumatum (quick one) is in order?
Good Luck!!