
Nobel Prize in Physiology or Medicine · 1976
Baruch S. Blumberg
He discovered the hepatitis B virus and co-invented its vaccine, the first vaccine that protects people against a cancer.
The Nobel citation: “for their discoveries concerning new mechanisms for the origin and dissemination of infectious diseases”
- Born
- July 28, 1925, New York, NY, USA
- Died
- April 5, 2011, Moffett Field, CA, USA
- Shared with
- D. Carleton Gajdusek
- Affiliation at the time
- The Institute for Cancer Research, USA
Medicine prize
1976
Shared with 1 other laureate.
Age that year
51years
Born in 1925.
Headline credited impact
70,000–680,000lives saved
Hepatitis B deaths averted by vaccination through 2025. How it was built
Sources cited
28
Fact-checked September 24, 2026.
- He found hepatitis B by accident while studying inherited blood proteins: the first clue was a New York patient's blood reacting with an Aboriginal Australian's.
- After his team began screening donated blood in 1969, hepatitis after transfusion at a Philadelphia hospital fell from 18% of patients to 6%.
- With Irving Millman he devised a vaccine made from harmless virus coat particles. The hepatitis B vaccine became the first vaccine shown to prevent a human cancer.
- On a 1977 trip to China he handed scientists a copy of his vaccine patent and connected them with Merck, which later helped China make its own vaccine.
- In his seventies he became the founding director of NASA's Astrobiology Institute, which studies how life began and whether it exists beyond Earth.
The breakthrough
Finding the hepatitis B virus and a new way to make a vaccine (1963-1969)
Hepatitis B is a virus that attacks the liver. Many people carry it for years without feeling sick, and decades later some develop scarring of the liver or liver cancer. In the early 1960s nobody could see the virus or grow it in a lab, so no one could tell who was carrying it. Blumberg was not even looking for it. He was studying how blood proteins differ from person to person around the world. He tested the blood of patients who had received many transfusions, to see whether they had made antibodies against other people's proteins. In 1963 his team at the National Institutes of Health saw an odd reaction: blood from a New York hemophilia patient reacted with just one sample in their test panel, from an Aboriginal Australian. They called the mystery substance Australia antigen. Over the next few years his group in Philadelphia showed that it turned up in people with hepatitis. It turned out to be the virus's outer coat. That gave blood banks a simple test to find carriers. It also gave Blumberg and Irving Millman an idea for a vaccine. Carriers' blood is full of harmless empty shells made of that coat, so they proposed purifying the shells and injecting them. It is like training a guard dog with a burglar's jacket instead of letting the burglar in: the immune system learns the coat and blocks real infections.[3],[4],[5],[6]
“All members of the carrier class should not be stigmatized because some can transmit hepatitis.”
What it meant for humanity
Blumberg's discovery turned hepatitis B from an invisible threat into a disease that could be tested for and prevented. The first payoff was safer blood. In the fall of 1969 his team began testing donated blood in Philadelphia and discarding units that carried the antigen. A year later, hepatitis after transfusion at Philadelphia General Hospital had fallen from 18% of patients to 6%. Within a few years the test was routine in blood banks across the United States and many other countries, and more sensitive versions followed. His lab also shared its testing materials with any researcher who asked, which sped up adoption. The second payoff was the vaccine. Blumberg and Irving Millman filed their patent in 1969, Merck took a license in 1976, and the first vaccine was approved in the United States in 1981. From 1986 the vaccine was made by genetically engineered yeast, and it became the first widely used vaccine made that way. By the end of 2020, 190 of 194 countries had added it to routine vaccination for all infants. The World Health Organization estimates that the share of young children with chronic infection fell from about 5% before vaccines to just under 1% in 2019. Because hepatitis B is a leading cause of liver cancer, this was the first vaccine to prevent a human cancer. In Taiwan, the first country to start a nationwide infant vaccination program (1984), carriage among children born after the program began fell from about 10% to about 1%. Blumberg also carried the work abroad: on a 1977 visit to China he lectured to thousands of scientists and shared his vaccine patent. The job is unfinished. WHO puts the number of people with chronic hepatitis B in 2024 at 240 million.
- After donor screening for Australia antigen began in 1969, hepatitis after transfusion at Philadelphia General Hospital fell from 18% of patients to 6% within about a year.[3]
- The hepatitis B vaccine became the first vaccine proven to prevent a human cancer. In Taiwan, liver cancer among children and teens fell from 0.57 to 0.17 cases per 100,000 a year after mass vaccination began in 1984.[5],[6]
- By the end of 2020, 190 of 194 countries included hepatitis B vaccine in routine infant vaccination. WHO estimates chronic infection among children under 5 fell from about 5% before vaccines to just under 1% in 2019, and 0.6% in 2024.[9],[17]
- A 2021 modelling study estimated that hepatitis B vaccination in 112 low- and middle-income countries from 2000 to 2030 will prevent about 29 million deaths over the lifetimes of those vaccinated.[11]
- In 1977 Blumberg gave Chinese scientists a copy of his vaccine patent and linked them with Merck, which later shared technical know-how so China could produce its own vaccine.[2]
Impact in numbers
Blumberg's work turned an invisible killer into a preventable disease. The blood test that grew out of Australia antigen made transfusions far safer from 1969 onward, and the vaccine concept he patented with Irving Millman led to one of the world's most widely used vaccines, now given to infants in almost every country. Most of the lives the vaccine saves lie in the future, because hepatitis B usually kills through liver cancer and cirrhosis decades after infection: a 2021 study estimates about 29 million deaths prevented over the lifetimes of children vaccinated in poorer countries from 2000 to 2030. Our number counts only deaths already averted by the end of 2025, and credits Blumberg with 20% of them. Others made essential contributions: colleagues who co-discovered and confirmed the antigen, the Merck and French teams who made and tested the first vaccines, the scientists who created the yeast-made version, and the health systems that deliver it. We add no number for safer blood, although it prevented many infections, because we found no reliable global total.
HealthFundamental science
Each number is the laureate’s credited share of a real-world outcome, cumulative to 2025. The whole outcome, the share of credit, and the reasoning are shown so you can check the arithmetic. Outcomes shared with other laureates are counted once on the impact page.
- Medium confidenceDirectModeledHealth
Hepatitis B deaths averted by vaccination through 2025
70,000–680,000
lives saved, credited share
That is 20% of 350,000–3.4 million lives saved since 1982.
How this number was built
Counts deaths already averted by end-2025, not lifetime benefits. Li et al. (Lancet 2021, VIMC, Table 2): hepatitis B vaccination averted 640,000 deaths (95% CrI 190,000-1.5M) in 98 low- and middle-income countries in 2000-2019 and 1.6M (460,000-2.9M) in 2020-2030. Annual impact is still rising, so we assign 40-55% of the 2020-2030 figure to 2020-2025. Low: 190k + 0.40 x 460k = 374k, rounded down to 350k. High: 1.5M + 0.55 x 2.9M = 3.1M, plus up to 10% for Taiwan, South Korea, rich countries and 1982-1999 = 3.4M. Lifetime figures (Toor et al. 2021: 29M; WHO: 7M for Western Pacific children born 1990-2014) are not counted. Blood screening excluded. Share 0.2: Blumberg found the antigen, tied it to hepatitis and devised the vaccine concept with Millman; co-discoverers (including Harvey Alter), vaccine makers, yeast-vaccine inventors and delivery programmes were also essential.[5],[10],[11],[12],[16]
Sources: The Lancet, via PubMed Central; eLife, via PubMed Central; World Health Organization Regional Office for the Western Pacific; Virology Journal (BioMed Central), via PubMed Central; Vaccines (MDPI), via PubMed Central
- Medium confidenceDirectModeledHealth
Children spared lifelong hepatitis B infection by vaccination
22–52
million people benefited, credited share
That is 20% of 110–260 million people benefited since 1982.
How this number was built
Lifetime benefit the deaths-to-2025 claim omits: chronic infection brings lifelong liver-cancer and cirrhosis risk. High: Nayagam et al. (s22) model that infant vaccination had prevented 210M new chronic infections by 2015; adding 2016-2025 births (1.365B, UN via OWID, s23) x 4 points = 55M gives ~265M, rounded down to 260M. Low, a simpler check: WHO (s9) says under-5 prevalence fell from ~5% before vaccination to just under 1% by 2019, 4 points. Cohorts born 1995-2014 (2.77B) at a gain rising linearly from 0 to 4 points (average 2) = 55M; 2015-2025 (1.51B) x 4 points = 60M; total 116M, rounded down to 110M. Counterfactual: no vaccine. Counts infections in vaccinated children, not transfusion infections averted by donor screening. Share 0.2, as on the deaths claim: Blumberg found the antigen and devised the vaccine with Millman; Alter (0.02), makers and programmes did the rest.[9],[16],[22],[23]
Sources: The Lancet Infectious Diseases, via PubMed; World Health Organization; Our World in Data; Vaccines (MDPI), via PubMed Central
- Low confidenceDirectModeledHealth
Transfusion recipients spared hepatitis B by donor screening, 2008-2025
320,000–1.2 million
people benefited, credited share
That is 20% of 1.6–6.2 million people benefited since 2008.
How this number was built
2008-2025 only. WHO: 91.8M donations in 2008, 118.5M in 2018; linear between, flat after = 1.99B. Median HBsAg-reactive rates by income group 0.01/0.29/1.96/2.81%, weighted by 2018 donation shares 40/34/24/2% (WHO 2021) = 0.63%: 12.5M units kept out. Infections averted per unit: 0.15 (Allain, Ghana: recipients over 10, often already immune) to 0.5 (Gocke 1972, US: 52% of recipients of antigen-positive blood were infected). Low x 0.9: 11% of donations not screened to standard (WHO 2011). 12.5M x 0.9 x 0.15 = 1.7M, rounded down to 1.6M; 12.5M x 0.5 = 6.2M. Only susceptible recipients count, so no vaccinated child from the vaccine claim is counted. Rough: medians, unconfirmed reactives. Share 0.2 (Alter 0.05, Yalow 0.01): Blumberg found the antigen and tied it to hepatitis; Prince, test makers and blood services did the rest.[5],[24],[25],[26],[27],[28]
Sources: World Health Organization (archived 16 May 2022); World Health Organization; Blood (American Society of Hematology), via PubMed; JAMA, via PubMed; World Health Organization; Virology Journal (BioMed Central), via PubMed Central
The double edge
No major harms from Blumberg's discoveries are documented, but there are real controversies. In his own Nobel lecture he warned that the blood test was creating a stigmatized group of carriers: some health workers who carried the virus were told to leave their jobs, even though most carriers pose little risk to others. The first vaccine, made from carriers' plasma, met public fear in the early 1980s because some plasma donors later developed AIDS, before the AIDS virus had been identified; that risk was never proven, and yeast-made vaccines soon replaced it. One early experiment by his team, which injected radioactive phosphorus into a terminally ill carrier to study the antigen, is described in a history of the field as somewhat questionable by today's ethical standards. His idea that hepatitis B makes carriers more likely to have sons, which an economist briefly used to help explain Asia's missing women, did not hold up in large studies.
- Minor
A test that could stigmatize carriers
Screening identified large numbers of healthy carriers. Blumberg's Nobel lecture records that some health-care workers who were carriers were told to leave their jobs and that carriers changed their social lives out of fear, even though most carriers are unlikely to spread the virus by everyday contact. He argued that carriers as a group should not be stigmatized.[3]
- Minor
AIDS-era fears about the plasma-derived vaccine
The first vaccine was purified from the plasma of chronic carriers. After the 1980 trial it emerged that some plasma donors later developed AIDS, at a time when the AIDS virus was unknown, and fears of infection held back acceptance. The risk was theoretical and never proven, and yeast-made vaccines replaced the plasma version from 1986.[5],[16]
- Minor
An experiment questionable by today's standards
To test whether Australia antigen particles contained genetic material, Blumberg's team injected radioactive phosphorus into a terminally ill carrier and studied the antigen in the patient's plasma. The virologist Wolfram Gerlich, in a history of the field, calls the approach a bit questionable by today's ethical standards, while stressing it was not comparable to the deliberate-infection studies done by others at the time.[5]
- Minor
The sex-ratio hypothesis did not hold up
Blumberg argued that parents who carry hepatitis B have more sons than daughters. An economist built on this to suggest the virus could explain about half of Asia's missing women, but a large study of births in Taiwan found only a tiny effect, and a 67,000-person cohort in China, studied by that same economist and colleagues, found none.[2],[15]
Against the odds
Blumberg was born in 1925 in Brooklyn, the son of a lawyer and the grandson of Jewish immigrants from Europe. No persecution of him personally is documented, and his story is mostly one of opportunity. But he grew up when American higher education openly limited Jewish students. From the 1920s many medical schools ran quotas. In 1933-34 only about 26% of Jewish applicants won places, against 46% of non-Jewish applicants. At Columbia's College of Physicians and Surgeons, the Jewish share of entering students fell from 47% in 1920 to 6% in 1940. As late as 1946, every one of 39 medical school application forms reviewed asked about religion, and some asked whether the family had changed its name. After World War II, investigations in New York and Philadelphia exposed the quotas, and a New York report found that Columbia and Cornell had selectively turned away Jewish applicants. Blumberg, a Navy veteran who had commanded a landing ship, entered Columbia's medical school in 1947, just as that system came under attack. He trained there, earned a doctorate at Oxford, and did his prize-winning work at the National Institutes of Health and in Philadelphia.
1940
Quota
The Jewish share of entering students at Columbia's College of Physicians and Surgeons, where Blumberg later studied medicine, fell from 47% in 1920 to 6% in 1940 under restrictive admissions. There is no record that Blumberg himself was turned away anywhere.[13]
1946
Discrimination
A 1946 review of 39 US medical school application forms found that all asked the applicant's religion, and a New York investigation found that Columbia and Cornell selectively rejected Jewish applicants. Blumberg entered Columbia's medical school the following year.[13],[14]
1943
War
He joined the US Navy in 1943, served as a deck officer on landing ships during World War II, and was commanding one of them when he left active duty in 1946.[2]
Jewish background
Blumberg was born in Brooklyn into a Jewish family. His parents were Meyer Blumberg, a lawyer, and Ida (Simonoff) Blumberg, and his grandparents had come to the United States from Europe in the late 19th century. He went to the Yeshiva of Flatbush, a Hebrew day school, where he read the Hebrew Bible in the original and studied rabbinic commentaries and the Talmud. He credited Talmud study with teaching him to reason through hard questions, kept going to a weekly Talmud study group for the rest of his life, and told The New York Times in 2002 that the Jewish idea that saving one life saves the whole world drew him to medicine.[2],[7],[8],[20],[21]
Key dates
July 28, 1925
Born in Brooklyn, New York, to Meyer Blumberg, a lawyer, and Ida Blumberg; he attends the Yeshiva of Flatbush for elementary school.[1],[2],[7],[8],[20]
1943
Joins the US Navy in World War II and serves as a deck officer on landing ships.[2]
1946
Graduates in physics from Union College, New York, and leaves active duty in command of a landing ship.[2],[7]
1951
Earns his medical degree from Columbia University's College of Physicians and Surgeons, then trains at Bellevue Hospital.[2],[7]
1957
Completes a biochemistry doctorate at Oxford and joins the National Institutes of Health to study inherited variation in blood.[2],[19]
1963
His team finds a new blood antigen, reacting between a New York hemophilia patient and an Aboriginal Australian, and names it Australia antigen.[3],[5]
1964
Moves to the Institute for Cancer Research (later Fox Chase Cancer Center) in Philadelphia to lead clinical research.[2],[19]
1967
Publishes evidence linking Australia antigen to viral hepatitis; it is later shown to be the coat of the hepatitis B virus.[3],[5],[6]
October 1969
Donor-blood screening starts in Philadelphia, and he and Irving Millman file a patent for a hepatitis B vaccine made from carriers' blood.[3]
October 14, 1976
Awarded half of the Nobel Prize in Physiology or Medicine, shared with D. Carleton Gajdusek.[1],[4]
1981
The first hepatitis B vaccine, developed from his concept, is approved in the United States.[6]
1989
Becomes Master of Balliol College, Oxford, serving until 1994.[2],[19]
May 1999
Becomes founding director of the NASA Astrobiology Institute at Ames Research Center, serving until 2002.[2],[19]
April 5, 2011
Dies of an apparent heart attack at Moffett Field, California, soon after delivering a keynote talk at a NASA conference.[1],[18],[20]
Sources
- 1.Baruch S. Blumberg - Facts · NobelPrize.org (Nobel Prize Outreach)
- 2.Baruch S. Blumberg - Biographical (1976 autobiography with 2006 addendum) · NobelPrize.org (from Les Prix Nobel en 1976), 2006
- 3.Australia Antigen and the Biology of Hepatitis B (Nobel Lecture, 13 December 1976) · NobelPrize.org, 1976
- 4.The Nobel Prize in Physiology or Medicine 1976 - Press release · NobelPrize.org (Karolinska Institutet), 1976
- 5.Medical virology of hepatitis B: how it began and where we are now (Gerlich WH, Virology Journal 10:239) · Virology Journal (BioMed Central), via PubMed Central, 2013
- 6.Baruch S. Blumberg, MD, PhD: Research · Fox Chase Cancer Center
- 7.Baruch Samuel Blumberg · Wikipedia
- 8.Baruch Blumberg: Early life and school (video interview) · Web of Stories
- 9.Hepatitis B - Fact sheet · World Health Organization, 2025
- 10.Estimating the health impact of vaccination against ten pathogens in 98 low-income and middle-income countries from 2000 to 2030 (Li X et al., Lancet 397:398-408) · The Lancet, via PubMed Central, 2021
- 11.Lives saved with vaccination for 10 pathogens across 112 countries in a pre-COVID-19 world (Toor J et al., eLife 10:e67635) · eLife, via PubMed Central, 2021
- 12.7 Million Deaths Averted through Hepatitis B Vaccination · World Health Organization Regional Office for the Western Pacific, 2016
- 13.The Jewish Problem in U.S. Medical Education, 1920-1955 (Halperin EC, Journal of the History of Medicine and Allied Sciences 56) · Journal of the History of Medicine and Allied Sciences (reprint hosted by the Jewish Historical Society of South Carolina), 2001
- 14.Jewish American Heritage Month: The Forgotten History of Quotas in American Medical School Admissions · Himmelfarb Health Sciences Library, George Washington University, 2023
- 15.Hepatitis B Does Not Explain Male-Biased Sex Ratios in China (Oster E, Chen G, NBER Working Paper 13971) · National Bureau of Economic Research, 2008
- 16.Global Perspectives on the Hepatitis B Vaccination: Challenges, Achievements, and the Road to Elimination by 2030 (Vaccines 12:288) · Vaccines (MDPI), via PubMed Central, 2024
- 17.Progress Toward the Elimination of Mother-to-Child Transmission of Hepatitis B Virus - Worldwide, 2016-2021 (MMWR 71(30)) · US Centers for Disease Control and Prevention, via PubMed Central, 2022
- 18.Baruch Blumberg dies at 85; helped on hepatitis B vaccine (New York Times News Service obituary) · The Bulletin (Bend, Oregon), 2011
- 19.Baruch S Blumberg, MD, PhD: A Life · Fox Chase Cancer Center
- 20.Baruch S. Blumberg, Who Helped Make Hepatitis Vaccine, Dies (obituary by H. Roger Segelken) · The New York Times, via the Internet Archive, 2011
- 21.Baruch (Barry) Blumberg (1925-2011): tribute by David Morrison · SETI Institute, via the Internet Archive, 2011
- 22.Requirements for global elimination of hepatitis B: a modelling study (Nayagam S et al., Lancet Infect Dis 16:1399-1408) · The Lancet Infectious Diseases, via PubMed, 2016
- 23.Number of births per year (UN World Population Prospects) · Our World in Data, 2024
- 24.Blood safety and availability (fact sheet, Table 1: prevalence of transfusion-transmissible infections in blood donations by income group) · World Health Organization (archived 16 May 2022), 2022
- 25.Global Database on Blood Safety: Summary Report 2011 (2008 data: 91.8 million donations) · World Health Organization, 2011
- 26.The risk of hepatitis B virus infection by transfusion in Kumasi, Ghana (Allain JP et al., Blood 101:2419-2425) · Blood (American Society of Hematology), via PubMed, 2003
- 27.A prospective study of posttransfusion hepatitis: the role of Australia antigen (Gocke DJ, JAMA 219:1165-1170) · JAMA, via PubMed, 1972
- 28.Global status report on blood safety and availability 2021 · World Health Organization, 2022
Fact-checked on September 24, 2026 by a separate AI fact-checking pass that re-opened the sources, with 11 corrections made. How we check
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