My husband almost never gets sick, but when he does, it's rarely a minor illness. A little over two weeks ago, he came down with a very severe, very rapidly-progressing respiratory infection. Within a period of 96 hours, it went from a mild cough with no fever to severe pneumonia and a fever over 40C. The doctor prescribed amoxicillin/clavulanic acid on the morning of the third day, but it didn't really have any effect. My husband only started to get better once the doctor put him on levofloxacin a couple of days later. I think there's a very good chance his infection was caused by some kind of drug-resistant bacteria, but they didn't do any cultures, so we'll never know for sure.
On the other hand, I seem to be getting fewer and milder respiratory infections in the past few years. Even though I've always been prone to respiratory infections (I used to get bronchitis and/or pneumonia pretty much every winter), and have become quite a connoisseur of antibiotics, the worst I came down with this time was a mild ear/sinus infection and extreme fatigue. I also managed to avoid catching the H1N1 flu despite staying home to care for my daughter while she had it in 2009.
The brain is a wonderful organ; it starts working the moment you get up in the morning, and does not stop until you get to work.