Maurice Hilleman, We Salute You

It has not gone unnoticed that – in conjunction with online vaccine misinformation – the number of cases of children contracting the measles has risen in recent years. Such is the severity and proliferation of cases, the US NFID has had to address the issue by urging members of the public to remain up to date with MMR vaccinations – a legacy public health recommendation from days when such reminders were deemed obvious rather than necessary. 

Although measles was declared eliminated in the US in 2000, there were 41 reported cases in the US in the first two months of 2024. Compare this to the 58 US cases reported in the whole of the previous year (1), and there are concerns of an escalating problem. Canada is also seeing the beginnings of a concerning increase in cases, with 17 confirmed this year. Europe also has a measles problem with 2,361 cases reported to the European Centre for Disease Prevention and Control (ECDP) by EU member states and European Economic Area countries. In January and February, the ECDP also noted an increasing number of EU/EEA countries reporting measles cases, with six fatal cases reported in Romania and one in Ireland (2). 

Prominent Canadian health journalist André Picard recently berated a skeptic on Twitter who asked, “Tell us why measles is so bad in 2024 when we born before 1950 got it without dying.” Picard responded in facts highlighting the “survivorship bias” implied: “In 1950, before a vaccine available [sic], more than 55,000 Canadian children contracted #measles. It was the leading cause of blindness, deafness and ‘mental retardation.’ And more than 100 children died. What is your point: That, in 2024, we should have more sick and dead children?” 

I’m very interested in the history of medicines and vaccines. You may have seen my previous blog posts on James Phipps, Ignaz Semmelweiss, and Rosalind Franklin. In light of the measles problem, I thought it would be apt to look into the history of the measles vaccine.

Maurice Ralph Hilleman is no household name, but within the vaccinology circuit, he is considered among the most influential and successful vaccinologists ever known, and was described by Anthony Fauci specifically as “one of the true giants of science, medicine and public health”(3). 

The developer of more than 40 vaccines, including for the prevention of mumps, rubella, Haemophilus influenzae type b, hepatitis A, hepatitis B, and chickenpox, Hilleman’s productivity is estimated to still be saving around eight million lives per year (4).

Born the eighth child of Montana farmers in 1919, Hilleman’s twin sister died at birth, with his mother following just two days later. Hilleman was raised in his uncle’s farmstead – for which he would later credit much of his success due to his familiarity with hens’ eggs (famously used for vaccine development).

Hilleman’s interest in science superseded the conservative religious upbringing, but when the time came to study, he had no money to do so. His eldest brother encouraged him to apply for a scholarship to Montana State University, where he later graduated top of his class (1941) and earned a fellowship to the University of Chicago, where he gained his doctorate in microbiology (1944) after proving that chlamydia infections were caused by a species of bacterium, Chlamydia trachomatis, which grows inside cells.

During his early career, Hilleman developed a vaccine against Japanese B encephalitis whilst working for ER Squibb & Sons (now Bristol-Myers Squibb). In 1957, Hilleman joined MSD to lead its new virus and cell biology research department. He was among the first to theorize that a 1957 outbreak of influenza originating in Hong Kong would become a pandemic. 69,000 people in the US died, but many, many more lives were saved by the 40 million doses of Hilleman’s vaccine that were manufactured and distributed (5). Hilleman was awarded the Distinguished Service Medal from the American military for this effort, which had to be repeated in 1968, during another flu pandemic, during which Hilleman and his team played a key role in developing a vaccine, of which nine million doses became available in a matter of months. Sounds familiar?

Leaving a legacy that extends far beyond the development of numerous life saving vaccines, including a Maurice R. Hilleman Chair in Vaccinology at the Children’s Hospital of Philadelphia; Merck’s Maurice R. Hilleman Center for Vaccine Manufacturing; the American Society of Microbiology’s Maurice Hilleman/Merck Award in Vaccinology; and Montana State University’s Hilleman Scholarship Program for students who “commit to work at their education beyond ordinary expectations” (6), Hilleman continues to be remembered more poignantly now than since before the pandemic by those emulating his success. 

For that reason, Maurice Hilleman, we salute you. Let’s hope this alarming trend is met with the same combination of productivity and ingenuity.