DIED. Albert Sabin, 86, medical researcher; in Washington. While the world most honors Jonas Salk as the developer of a vaccine for polio, the paralyzing illness that terrified America after World War II, his great rival Sabin devised the oral version, which did the most to conquer the disease. During the war, Sabin's vaccines protected thousands of U.S. troops against such diseases as dengue fever and Japanese encephalitis.