No one knows what it is, or why it's spreading like wildfire. The infinitologists claim that it's the wrath of the universe while the psychiatric technicians says that it is a form of isolation sickness, feeding into the fears and mental weaknesses of the stricken. But no one knows.
Those who have been sucked into the maddening spiral of full blown VPS are a danger to themselves and others. Insomnia, paranoid delusions paired with homicidal and suicidal tendencies are just the tip of the iceberg.