This stuff scares me.
There has been an ongoing outbreak of Marburg Virus in Angola for well over a month now, and they can't seem to control it. Marburg Virus first came to my attention as a plot device in the unfortunately cancelled TV series Millenium. At first I thought it was fiction; a made-up desease some Hollywood-type deliberately conjured to be worse than Ebola.
Nope. It's all true. And it's highly infectious.
All it takes, at least in theory, is for one person to come into unexpected, unknown contact with the virus and get on a plane to the United States or Europe. Don't believe it can spread like that? Well there is a reason I linked in a previous post to the "Zombie Infection Simulation." It is an admitedly simplified, but fairly accurate representation of just about any infectious scenario.