Maurice Ralph Hilleman (August 30, 1919 – April 11, 2005) was a leading American microbiologist who specialized in vaccinology and developed over 40 vaccines, an unparalleled record of productivity. According to one estimate, his vaccines save nearly eight million lives each year. Many have described him as one of the most influential vaccinologists of all time. Of the 14 vaccines routinely recommended in current American vaccine schedules, Hilleman and his team developed eight: those for measles, mumps, hepatitis A, hepatitis B, chickenpox, Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae bacteria. During the "1957-1958 Asian flu pandemic", his vaccine is believed to have saved hundreds of thousands of lives. He also played a role in the discovery of antigenic shift and drift, the cold-producing adenoviruses, the hepatitis viruses, and the potentially cancer-causing virus SV40. Biography Early life and education Hilleman was born on a farm near the high plains town of Miles City, Montana. His parents were Anna (Uelsmann) and Gustav Hillemann, and he was their eighth child. His twin sister died when he was born, and his mother died two days later. He was raised in the nearby household of his uncle, Bob Hilleman, and worked in his youth on the family farm. He credited much of his success to his work with chickens as a boy; since the 1930s, fertile chicken eggs had often been used to grow viruses for vaccines. His family belonged to the Lutheran Church–Missouri Synod. When he was in the eighth grade, he discovered Charles Darwin, and was caught reading On the Origin of Species in church. Later in life, he rejected religion. Due to lack of money, he almost failed to attend college. His eldest brother interceded, and Hilleman graduated first in his class in 1941 from Montana State University with family help and scholarships. He won a fellowship to the University of Chicago and received his doctoral degree in microbiology in 1944. His doctoral thesis was on chlamydia infections, which were then thought to be caused by a virus. Hilleman showed that these infections were, in fact, caused by a species of bacterium, Chlamydia trachomatis, that grows only inside of cells. Career After joining E.R. Squibb & Sons (now Bristol-Myers Squibb), Hilleman developed a vaccine against Japanese B encephalitis, a disease that threatened American troops in the Pacific Ocean theater of World War II. As chief of the Department of Respiratory Diseases at