The scientist who saved more lives than any other in the last 100 years almost didn’t become a scientist at all. Maurice Hilleman was born in 1919, during the Spanish flu pandemic. His twin sister arrived stillborn and his mother died soon after of eclampsia. He was adopted by his aunt and uncle, who raised him on a family farm just down the road from his domineering and distant birth father. Ironically, his father was distrustful of medical science and prevented him from receiving any vaccinations. He was nearly killed by diphtheria at the age of 8.
As a bright but poor kid growing up in Montana during the Depression, Hilleman figured he’d be lucky just to get a job at the local J.C. Penney. But thanks to the encouragement of one of his brothers and a full scholarship to Montana State University, Hilleman acted on his childhood fascination with chemistry and microbiology. And we should all be grateful that he did. Because that intense, lanky, brilliant young man went on to create more than 40 vaccines, many of which have saved untold millions of lives.
There are 16 vaccines given in the standard vaccination schedule. Maurice Hilleman developed 9 of them. Specifically, he led the creation of vaccines for measles, mumps, rubella, chickenpox, hepatitis A, hepatitis B, pneumococcus, meningitis, and Haemophilus influenzae Type B. This is an unparalleled contribution to humanity.
If we’re fortunate, most of us have not personally encountered the worst of these diseases. Some of them seem almost quaint, like something from a Laura Ingalls Wilder story. Take measles, for example. To me, it brings to mind vague images of some kind of red rash and cold-like symptoms. And that’s actually how it starts out: runny nose, cough, and mild fever. But the measles virus can be deadly. In the worst cases, it causes encephalitis and fatal pneumonia. As recently as the early 1960s, measles killed 8 million children a year, worldwide. In 1968, Maurice Hilleman and his team at Merck refined a vaccine that had been developed by John Enders, greatly reducing its side effects. Hilleman’s version is the only one that has been used in the United States ever since. In September 2016, the World Health Organization declared measles eradicated from North and South America.
Maurice Hilleman was part of an incredible burst of vaccine inventions after World War II. But it took centuries of discovery and work to make that burst possible, and Hilleman was always quick to give credit to the geniuses who came before him. Edward Jenner created the world’s first vaccine, for smallpox, in 1796. It was almost 90 years before Louis Pasteur created the second vaccine, for rabies, the deadliest disease affecting man with a nearly 100% fatality rate. After that, the era of modern vaccines began to accelerate as the science and production capabilities improved in the first half of the 20th century. Vaccines for diphtheria, tetanus, yellow fever, whooping cough, and influenza were produced in this period. With every decade that passed, scientists added to the list of vaccine-preventable diseases. But Hilleman wanted to go further, and faster. He made it his goal to prevent every common infectious disease that killed or harmed children. He didn’t quite get there, but he spent his entire life and every moment of his long career getting as close as he could.
Hilleman embodied a powerful combination of intellect and tireless willpower. During graduate school at the University of Chicago, he ate one meal a day because that was all he could afford. Yet he began to make groundbreaking discoveries even before finishing college. As part of his doctoral research work, he found that chlamydia was actually caused by an unusual bacterium and not a virus, as had been previously thought. His work was vital in leading to a treatment for one of the most common sexually transmitted diseases.
During the 1940s and 50s, Hilleman worked for the U.S. Army’s Walter Reed Institute. He was put in charge of detecting and preventing viral pandemics. It was here that he carried out one of his most extraordinary achievements: he became the only person in history to accurately predict a flu pandemic and develop a vaccine to fight it. He recognized patterns in the way influenza viruses evolved over time, and found that abrupt “shifts” in their genes could change them quickly enough that people would be left with no immunity to the new version. To this day, we benefit from this finding every year when we get a flu vaccine which has been updated to account for these genetic changes. Back in 1957, Hilleman determined that the Asian flu, which had broken out in Hong Kong, was going to spread around the world as a lethal pandemic. This illness, which hadn’t flared up in 70 years, had the potential to be extremely infectious and deadly. Hilleman tested hundreds of military and civilian blood samples and found that not a single one had any immunity to Asian flu. But he couldn’t get anyone to believe him. Exasperated, he ambushed the U.S. military’s head of the Influenza Commission during dinner at a Washington D.C. club and demanded he look at the data. The director was horror-struck by what he saw, and Hilleman was immediately given approval to make the vaccine. He worked with 6 companies to produce over 40 million doses in just a few months. When the Asian flu entered the U.S. in September 1957 just as Hilleman had predicted, it infected more than 20 million Americans and killed 70,000. But Hilleman’s bold actions prevented millions from being infected with Asian flu and saved many thousands of lives.
Maurice Hilleman spent the rest of his career working for Merck Research Laboratories. He created more than 20 vaccines over the next three decades. He was tenacious, methodical, and equally obsessed with results and safety. He was tough on his staff and hilariously profane, but also intensely loyal and nurturing to them. In return, his workers adored him and worked hard to meet his high standards. Those who didn’t make the cut were represented by shrunken heads made from apples, which he gleefully kept in a row behind his desk. Hilleman knew he could be a tyrant, but he relished the role and knew how effective it could be. Near the end of his life, he said:
“The most apt description of me was by Roy Vagelos, who said that on the outside I appeared to be a bastard but that if you looked deeper, inside, you still saw a bastard.”
In spite of his mercurial nature, he was a big-hearted man who dedicated his life to saving others, with very little fanfare. It’s sad but really not surprising that most of us have never even heard the name Maurice Hilleman. While not without an ego or a sense of professional pride, he simply wasn’t interested in fame or self-promotion. As a result, he was largely ignored by the public and the press. At his core, he was a humble man, devoted not only to his work but to his wife and two daughters. He never named a single one of his vaccines after himself and was unfailingly respectful of others’ work. If he found a new version of a vaccine that was superior to his own, he would set his work aside and advocate the use of the new one. Above all, he was interested in results and progress, regardless of the source.
The one vaccine whose name bears even a remote connection to Hilleman is the mumps vaccine based on the “Jeryl Lynn” strain of the virus. Jeryl Lynn is the name of one of Hilleman’s daughters. In 1963, Jeryl had a sore throat one night and woke up her father, who quickly realized she had the mumps. Mumps is another one of those “old” diseases that sounds pretty innocuous these days. But at the time, it infected 1 million people per year in the U.S. alone, and sometimes caused meningitis, paralysis, birth defects, sterility, and even death. So Hilleman responded as the virologist he was, and took a culture from his daughter’s throat. Over the next four years, he worked to weaken Jeryl’s strain of the virus and used it to create the best and safest mumps vaccine ever produced. In the 50 years since, Hilleman’s vaccine has been given to hundreds of millions in the U.S. and many other countries, and every single dose is derived from his daughter’s strain of mumps.
Maurice Hilleman died of cancer in 2005. During his final months, he shared the stories of his life and career with Paul Offit, MD, who wrote a remarkable book about Hilleman called Vaccinated: One Man’s Quest to Defeat the World’s Deadliest Diseases. If you’d like to learn more about Hilleman and the science and history of vaccines, I recommend it highly.
Think of Dr. Hilleman when your child gets a cold, knowing how much more terrifying a sore throat would have been to parents a century ago. Think of him when you get your flu shot. Think of him when you hear a news story about the eradication of another disease. Think of him, and imagine how different the world would be without his lifesaving work and its impact on hundreds of millions of people.
Maurice Hilleman was a mighty fine person.