Soola's Disease is a disease that Andalites may get which will eventually kill them. It attacks their nerves and causes excruciating pain as time goes on, although this pain can be soothed with medication. Because the disease is part of the Andalite's DNA, it cannot be cured by simply morphing as the Andalite's genetic code will still have the disease. The only known cure is for the infected Andalite to acquire and morph another Andalite without the disease, willingly becoming a nothlit, but this approach is considered shameful.