Obituary: Maurice Hilleman

Scientist who developed a multitude of vaccines and saved countless lives

By Kristen Jill Kresge   

Dr. Maurice Hilleman 

Maurice Hilleman was without doubt one of the towering figures of 20th Century science. Since his death on April 11, tributes have consistently cited him as the medical scientist responsible for saving the most human lives. 
Hilleman let no obstacles stand in his way and this led him through one of the most distinguished careers in the history of vaccinology. Developing one successful vaccine is certainly a milestone, but Hilleman had a career littered with milestones. In total he developed more than 40 vaccines, including 5 of the 14 immunizations routinely given to children and adults today. Vaccines against measles, mumps, rubella,Haemophilus influenzae type B, and hepatitis B are just some of Hilleman’s contributions to the field. He also pioneered the combination of the measles-mumps-rubella (MMR) vaccine as a single immunization.

Hilleman was raised on a farm in Montana, an environment he considered “a crucible for learning science”, and he maintained his rural demeanor throughout his life. “Maurice believed there were very simple, profound truths to the way you do science and develop vaccines. Even though it is very complicated work, he always had a clear path,” recalls Mike Goldrich of the International AIDS Vaccine Initiative (IAVI). At a public memorial service held in his honor on April 25, Hilleman was described as “an affable curmudgeon”. “At times you have to be cantankerous. It may not get you prizes, but it is what is needed for you to develop more vaccines than any other person,” adds Goldrich. “He was like the Yogi Berra of science,” referring to the baseball legend known for his pithy insights. Goldrich remembers Hilleman as a steadfast—maybe even stubborn—scientist and humanist who dedicated his life to protecting people from disease.

Hilleman was awarded the Lasker Public Service Award and the US National Medal of Science. Yet even among other scientists, the number and importance of Hilleman's contributions to the field were underappreciated, perhaps because he was known best for his applied science rather than basic research. But his contribution to new fundamental knowledge was still immense; he was the first to work out how to serotype microorganisms (Chlamydia spp.), he discovered SV40 and the adenoviruses, he was the first to purify interferon and show that it was induced by double-stranded RNA. He was also the first to describe the phenomenon of antigenic shift in influenza virus, the genetic reassortment that occasionally throws up new pandemic strains.

This latter understanding led to him almost single-handedly averting an influenza epidemic in the US. In 1957 he noticed a report of a new outbreak of influenza in Asia and realized a new pandemic was on its way. He obtained samples and worked nine 14-hour days with his team to confirm that a new influenza virus strain was responsible for this ‘Hong Kong flu’. Knowing that the US population would have no immunity to this strain, he convinced manufacturers that production of a new vaccine was imperative, even providing the virus stock samples. As a result the death toll in the US from Hong Kong flu was a relatively modest 69,000 people rather than the predicted one million.

Many of his outstanding accomplishments came during the subsequent 28 years he spent at the Merck Research Laboratories in West Point, PA, an association he maintained in an advisory capacity right up until his death. Emilio Emini of IAVI spent 20 years at Merck and recalls that “Hilleman was my hero. He was the scientist who set the standard for what my colleagues and I wanted to accomplish. Of course, the standard proved to be too high for any of us.”

Occasionally, Hilleman seemed to have even more gravitas than that usually accorded to such an exceptional scientist. Pat Fast of IAVI recalls a high-level advisory council meeting at the National Institutes of Allergies and Infectious Diseases where Hilleman was advocating decisive action. A storm was brewing outside and each proclamation from Hilleman was met with a huge clap of thunder. “It was as if there was endorsement from on high,” remembers Fast. “No one seemed very surprised.”

Even well into his retirement, Hilleman remained active in the field. When it came to AIDS vaccines, Hilleman recommended a “Manhattan Project” style approach, suggesting that the only way to tackle the extensive scientific difficulties was to get the best people, whether from academia, industry, or government, together in the same building where they could work on solving each problem.

At his memorial service, a quote from Hilleman summed up his ethos. “Well, looking back on one’s lifetime, you say, ‘Gee, what have I done—have I done enough for the world to justify having been here?’ That’s a big worry—to people from Montana, at least. And I would say I’m kind of pleased about all this. I would do it over again because there’s great joy in being useful.”

The number of lives that Hilleman’s vaccines have saved is immeasurable—one estimate has put it at 8 million lives each year. His passing marks the end of a life that saved so many millions of others.