Sars
The CBC FAQ Fred posted is actually from the W.H.O. site, where you can find a lot of other information about SARS, including daily status reports, counts of cases, what is known and what is being done, etc.:
http://www.who.int/csr/sars/en/
While I think the risk to the hobby is pretty low right now I'd be worried that all it would take is one "super spreader" to visit several SP's, and suddenly it could spread to the whole community--it'd have a few days to spread before symptoms started to show.
Any idea how many "degrees of separation" there are between SPs via clients?
Fortunately most people with SARS are doing OK so far--it's killing 4-5% of those infected worldwide (which is quite a high number for an infectious disease). The trouble is that many of those who get it require a mechanical ventilator in order to survive it.
That's fine so long as the number of cases remains small. The fear in the medical community is that if SARS breaks out into the general public there wouldn't be enough mechanical ventilators to go around. It's putting a severe strain on the hospitals already.
(edited: added link deeper into WHO site. Sorry Goober, I didn't realize I could post to this thread or I would have.)