Sick again.

About 5 weeks ago I was down with a nasty flu that caused me to miss 2 days of work, and about 3 weeks ago I was slammed with a killer cold. I still have the cold so on Sunday I went to see the Dr, and as it turns out it's not a cold at all, but a bacterial sinus infection that has moved to my larynx giving me laryngitis ( no voice at all folks ), affected my lungs so that I wheeze all the time and can't get a nice deep breath of air, I sneeze/cough all the time, and my eyes are so swollen/red from the sneezing that I need to put drops in several times a day as well. That leaves me on 4 prescriptions and several days off work because I can't answer phones with no voice. It seems that since I moved to BC I get sick every year about this time and I can't figure out why. I take my multi vitamins as well as Vitamin C every day, I wash my hands frequently to avoid bringing germs home etc, but I still get pretty sick when every one else I'm in close contact with ( Frank, Hike, co-workers etc ) seem to be fine. What could be causing me to get sick like this when I never used to get sick at all???