Well, it depends.
If there is talent, then the education is not needed. However, if someone lacks the talent then an education certainly will help and be the base from which that person can grow and carry on.
Everyone can benefit from art education of course but I believe there are many artists with a natural talent that still make it big without it. The best thing to do is first determine if illustrating is truly a passion for you. If this is something you really want to do with your life then go for it! If you believe you are not well prepared and doubt your abilities to draw and paint then go to art school.
Draw, practice, read, get informed, look at life differently, draw, practice, observe in detail other artists' work, draw, practice, read the internet, ask questions, read interviews, open an art related blog, draw and practice.
If you think I mistakenly wrote "draw and practice" several times, well it wasn't a mistake. You really need to draw and practice, a lot! The drawing and practicing actually never stops. An artist evolves each and every day by drawing. It's the only way.