In the spring of 1957, American microbiologist Maurice Hilleman read an article in The New York Times that left him greatly alarmed. “It said that there were all these children taken into dispensaries in Hong Kong, twenty thousand people lined up,” he said, describing the hospital scene in China in an interview years later. “My god, this is the pandemic,” he remembered thinking. “It’s here!” As a scientist who studied influenza and its mutations, Hilleman knew the virus could be stopped with a vaccine. But he had no time to lose.
Today, few people outside the immunology field recognize Hilleman’s name. Unlike Louis Pasteur, who developed vaccines for rabies and anthrax, or Jonas Salk, who created one for polio, Hilleman never basked in fame’s limelight, but he’s credited with saving more lives than any one person in modern history. He created more than 40 vaccines, including the staple trio of measles, mumps and rubella (MMR), hepatitis A and B, influenza and chickenpox, to name a few. Experts estimate that Hilleman’s vaccines save about 8 million lives a year.
Born in rural Montana, Hilleman lost his mother and his twin sister at birth. Before she died, Hilleman’s mother asked her husband to take care of the older children but to send Maurice to be raised by his aunt and uncle, a childless couple. So Hilleman grew up on a family farm, weeding patches and picking beans and tending to chickens, keeping the coop clean and collecting eggs, experience that would come in handy years later. It was a time when childhood diseases killed thousands, and the memories of the 1918 flu pandemic were still vivid. After Hilleman earned his Ph.D. in microbiology and chemistry, he made vaccine development the focal point of his career. “He was driven like no other person I met before,” says Paul Offit, a pediatrician and immunologist who wrote Hilleman’s biography, Vaccinated: One Man’s Quest to Defeat the World’s Deadliest Diseases. “He was motivated by one thing — he wanted to try and make vaccines for every disease that could possibly hurt or kill a child.”
Reading The New York Times’ descriptions of children with “glassy” eyes, Hilleman could see that threat. At the time, he worked at Walter Reed Hospital, says epidemiologist and public health scholar Rene F. Najera, who also runs the vaccines history blog for The College of Physicians of Philadelphia. Walter Reed is a military hospital that monitored the influenza outbreaks around the world, along with the World Health Organization. But when Hilleman announced his prediction that the virus would reach the United States in September of that year and trigger a pandemic on the second or third day of school, he wasn’t taken seriously at first. “I was declared crazy,” Hilleman says in Offit’s book. Thomas Francis, who directed the Influenza Commission for the military, responsible for controlling the disease with vaccines, didn’t think a vaccine was needed.
Meanwhile, the virus, dubbed the Asian flu, was well on its way. First appearing in February 1957 in the Guizhou province in southwestern China, it reached the Hunan province by March, Taiwan by April, and the Philippines by May, making landfall in India and Japan later in the month. Hilleman managed to get a virus sample from an American marine stationed in Asia. When he examined it, he saw that it was a new influenza strain that most people wouldn’t have antibodies to — except for a few elderly people who had survived the 1889-1890 influenza outbreak. Yet because, unlike now, people didn’t cross the globe in a matter of hours, Hilleman still had a few months. He grew the virus in the lab, showed his findings to Francis and proved his point, Offit writes in his book. “My god, it’s a pandemic virus,” Francis finally agreed, looking at the data.
Sidestepping the Division of Biologics Standards, the government agency responsible for regulating vaccines, Hilleman sent his viral samples directly to six vaccine manufacturing companies. In his own words, he “bypassed the bureaucratic red tape” in the interest of time. He also did something few microbiologists would know to do, unless they had once reared chickens: He called chicken farmers and asked them not to kill off their roosters because vaccine makers would need a lot of eggs.
At the time, vaccines were made by growing pathogens in chicken eggs. As viruses multiplied inside the eggs for several generations, they became better at devouring chicken cells while weakening their ability to destroy human ones. When given to people, the attenuated germs wouldn’t make them sick but would elicit an immune response. “After a few generations, the virus becomes more accustomed to chickens than to humans,” Najera explains. “So when you inject it into someone’s arm, it doesn’t give them the infection but gives them the immunity.” To create millions of vaccines, the manufacturers would need loads of fertile eggs, but typically, farmers would get rid of roosters at a certain point in the season. Hilleman fixed that problem.
The virus finally reached the U.S. by summer of 1957 and outbreaks started to happen — one after a church conference in Iowa, another one among Boy Scouts in Pennsylvania. Luckily, the first vaccines were ready by June, and vaccinations began in July, with 40 million doses distributed by late fall.
At the time, vaccine hesitancy wasn’t a problem. On the contrary, there was much excitement about immunization and vaccines because they had shown tremendous promise in beating infectious diseases. “The polio vaccine trials that took place in 1954-1955 were hugely successful,” Najera says. “So there was this trust that if vaccines saved us from polio, then this one would save us from the flu.” So people wanted their shots, and they lined up to get them.
Hilleman bypassed the bureaucratic red tape on other occasions too. When his 5-year-old daughter, Jeryl Lynn, woke him up one night in in 1963, complaining of a sore throat, he felt a lump at the angle of her jaw and realized she had the mumps. Back then, the mumps virus sickened a million people a year, causing anything from simple gland swelling to meningitis, seizures, deafness, paralysis and death. Hilleman was worried, but he also knew he had a unique opportunity to exterminate the scourge — and not only in his daughter.
At the time, Hilleman worked at Merck, so he drove to his lab in the middle of the night and returned with a cotton swab and a vial of nutrient broth. He swabbed his daughter’s throat, put the viral samples into the broth and then grew them in chicken cells for a vaccine. Three years later, Jeryl’s younger sister Kirsten received the still-experimental mumps shot, made from the virus that had attacked her sibling. Dubbed the Jeryl Lynn vaccine, it was approved and available to other children shortly after. In his book, Offit writes that from the time the vaccine was licensed in 1967 to 2000, it had prevented nearly a million children a year from getting meningitis or going deaf. Using the vaccine, a number of European countries eradicated the mumps entirely. As virologist and writer Alan Dove wrote in a Nature article, “Jeryl recovered from the mumps virus, but the mumps virus never recovered from infecting Jeryl.”
Hilleman spent his life trying to save the lives of other people and lost his own to cancer in 2005. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, who had known Hilleman, described him in a commemoration video as being focused like a laser beam. “He was someone who used a combination of intellectual brilliance, creativity with this amazing ability to see the big picture and get things done in a totally no-nonsense way,” Fauci said. Offit adds that Hilleman was a strong leader who wasn’t afraid to ruffle feathers and take matters into his own hands. “He commandeered this country,” Offit says. “People listened to him because he was right so much, and that enabled him to do things because he was such a strong, clear voice. The type of a strong clear voice we don’t have right now.”