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. He has been described as one of the most influential vaccinologists ever. He has been called the "father of modern vaccines". Robert Gallo called Hilleman "the most successful vaccinologist in history". He has been noted by some researchers as having saved more lives than any other scientist in the 20th century.
Of the 14 vaccines routinely recommended in 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 influenza pandemic in Southern China, his vaccine is believed to have saved hundreds of thousands of lives. He also played a key role in developing the vaccine for the Hong Kong flu. 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.
Source : Wikipedia