LA JOLLA, Calif. (AP) _ Dr. Jonas Salk, the medical pioneer who developed the first vaccine to prevent polio's crippling rampage and later tried to devise a treatment for AIDS, died Friday. He was 80.

Salk died of heart failure at Green Hospital in La Jolla at 12:23 p.m., said Anita Weld, a spokeswoman for the Salk Institute.