On April 17, 1957, Maurice Hilleman realized that a pandemic was en route to the United States. That day, The New York Times reported a major flu outbreak in Hong Kong. One detail in particular caught the doctor’s attention: in long queues for clinics, the newspaper said that “the women were carrying glass-eyed children attached to their backs”. He quickly got to work, announcing that a pandemic was coming and pushing to develop a vaccine by the time school started again in the fall.
The first pandemic occurred in southwest China’s Guizhou Province in February 1957. By the time Hilleman learned of it in April, Time reported that about 250,000 Hong Kong residents – 10% of the region’s population – are receiving treatment for the disease.
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The day after the story was read, he sent a cable to an army general medical laboratory in Zama, Japan, asking staff to investigate what was going on in Hong Kong. A doctor identified a member of the United States Navy who was allegedly infected in Hong Kong and returned the soldier’s saliva to Hilleman in the United States so that he could study the virus.
The 1957 virus moved
As chief of respiratory diseases at the Walter Reed Army Institute of Research in Washington, D.C., Hilleman “had access to a large amount of serum from people of different ages in the previous years and decades,” says a pediatrician. Paul A. Offit, who is director of the Vaccine Education Center at the Children’s Hospital of Philadelphia and is the author of Vaccinated: one man’s quest to defeat the world’s deadliest diseases.
In his work with Walter Reed, Hilleman had made the critical observation that the two key proteins of the influenza virus – hemagglutinin and neuraminidase – undergo slight modifications, or “Drifting” between seasons (this idea helped him predict the need for annual flu shots).
Comparing the Navy’s virus to previous influenza viruses, “what he discovered is that there has been this dramatic change,” says Offit. “These two proteins were completely different from what they were before. They hadn’t just drifted, they had changed. This new virus was a completely different strain of the flu.
Hilleman could not find any evidence of the population’s immunity to this new strain, so he sent the virus to other health organizations to confirm his findings. These organizations discovered that the only people who had antibodies to the virus were a small group in the 1970s and 1980s who had survived the “Russian flu” pandemic in 1889 and 1890.
Armed with this knowledge, Hilleman issued press releases announcing that a new influenza pandemic had arrived and would reach the United States by September 1957. Although he encountered some resistance, he succeeded in convincing companies to start working on flu vaccines to be ready by then. Fertilized chicken eggs would be needed for this production, so he told companies to remind farmers not to kill their roosters at the end of the hatching season.
Getting a vaccine for a new strain of flu is very different from making a vaccine for something completely new like COVID-19, the new coronavirus that appeared in 2019. Doctors and scientists first developed vaccines against the viable flu in the 1940s, so they weren’t going to scratch when they went to work on the 1957 flu vaccine. Yet Hilleman bypassed regulators in his efforts to advance the vaccine because he feared that these organisms do slow down the process.
When the flu hit the US, a vaccine was ready
When the new strain of influenza hit the United States in September, as Hilleman predicted, the country was ready with a vaccine. The virus, dubbed the “Asian flu,” has killed around 70,000 Americans and one to four million people worldwide, but experts suggest it would have killed many more without the vaccine. At the time of Hilleman’s birth, the “Spanish flu” from 1918 to 1919 killed an estimated 675,000 Americans and 50 million people worldwide.
“It’s the tricky thing in public health,” says Alexandra Lord, president of the division of medicine and science at the Smithsonian National Museum of American History in Washington, D.C.
“When things really go well, it’s very difficult to say,” so many lives have been saved, “because we don’t know what would have happened without it,” she said. “And so, even if it is impossible for us to say exactly how many lives have been saved, I think it is good to say that it has radically reversed a pandemic.”
Before his death in 2005, Hilleman helped develop more than 40 vaccines, including many for childhood illnesses. For this work, experts credited him with having saved millions of lives. In 1988, he received the National Medal of Science for his contributions to public health.