IBitis
A deadly disease that's known to cause insanity, insomnia, and often death. Symptoms include dark bags under your eyes, excessive yawning, hair loss, fatigue, loss of appetite and shaking. Not to be confused with senioritis, this disease infects all IB students around the world.
That kid has the worst case of IBitis I have ever seen; he doesn't sleep, doesn't eat, and his eyes look constantly bruised.