Scientific American writes about EpiSims, a program that simulates the spread of an infectious disease throughout a population, taking into account the social interactions of the people within it. [via Slashdot]
This is a good time to point out that I conflated a couple of different issues when I rambled about the spread of HIV in the comments here. The range of cell types that a virus can infect, the ease with which a virus can cross from one individual to another, and the damage that a virus causes when it infects (at the cellular and gross levels) are all conceptually different attributes of an infection; but, to make things more complicated, they are deeply intertwined. The important thing to remember, though, is that virulence—the disease-causing power of a pathogen—and infectiousness—the ease with which it spreads—should at least be kept separate in your mind when you try to predict the behaviour of a bug.
[When I found out that the NIH had put the epidemiology chapter of Medical Microbiology online for free I was going to point you at this diagram, but a quick glance was enough for me to realise that it’s worse than useless.]