I had this thought earlier today before reading this: Schools have been spreading illness for a long time. That feature may be considered just as important as bullies and mind-rottingly boring curriculum.

Seriously if they were going to install such things would they really have to close the schools? No. It shouldn't take more than a few hours. Which could be done after hours or over the weekend or over a holiday weekend. Or over summer break for the equipment and then a quick visit to install the virus.

The good thing is that warnings like this focus more eyes on potential problems.