Underlying Health Issues

Underlying Health Issues.
Three words that you read as the excuse for all the recent swine flu deaths.
I see these words everywhere, in all the stats and all the news stories and the macabre mummy in me wants full details of what they mean.
So far I've guesses at tonsilitis, some kind of lung thing and probably lots of colds that happened to be raped and pillaged and mutated by H1N1.
You see I'm so used to interrogating every medical aspect of my little man's life, I'm thinking of studying medicine so I never have to rely on a doctor's opinion at all. So when I read something like this, something that could easily be the difference between getting over a case of swine flu (which did I mention is just one away from us at work, in the family, at nursery...) I need to know more
I need to pry and have details because my house is full of underlying health issues, complicating the ordinary run of our lives and meaning I have be as observant as I am.
So when does an underlying health issue become an overarching excuse for tragedy and illness?
Is there more I can do than ruthlessly medicating to get rid of the horrid ear infection in one boy, and checking the temperature and watching and listening for the slightest physical sign of change in them both.
yet there's a rattle in my chest and a cold that won't go away that I'm seemingly in denial about.
does that count as Underlying?
can my underlying infect them and turn into theirs?
it's all so confusing and I fear I've finally tipped into neuroticism?
how do I avoid us being part of those headlines?
how do I get them to take my vulnerable little boy seriously?
and will we get to go on holiday on Sunday?