Interesting story, pickel.
Viruses don't tend to survive well on inanimate surfaces for long, as they require the presence of living cells to survive in. The cause of the outbreak was thought to be bacterial, and bacteria can survive for quite some time outside living cells with no problem.
It's quite possible this bacteria was on the keyboards, and if some irritant (eg smoke, or even screen flicker) caused the students to rub their eyes after touching the keyboards, then transmission of the bacteria is quite possible.
The key to avoiding any kind of infection is good hygiene. Make sure you wash your hands before eating, or sticking your fingers into any body cavities (including the nose

).
We live surrounded by bacteria and viruses, some of which can cause disease in us. Our best defence is good health and good personal hygiene.
Cheers
Mick