Not that they are aware of. A daughter and her husband caught it and came through fairly easily with no problems. My big sister is fighting it right now, but she said that forcing herself to do breathing exercises and getting our of bed and moving around the house has helped a great deal. Hope she doesn't end up with any lasting effects. She said the worst thing was sleeping sitting up for two nights because she couldn't breathe (which basically meant no sleep for two nights). The nights seem to be the worst - my daughter said that, too.