History of Vaccines – Part 4

Fourth and last part of a series of articles where you will learn how vaccines came about and how they have evolved over the years.

By Pierina D’Amico

Translation by Sumit Khanna 

In “Vaccine History – Part 3”, we looked at what happened during the second generation of vaccines. At that time, there were achievements against anthrax, cholera, rabies, tetanus, diphtheria, and plague. This latest article looks at the advances that occurred in the 20th century and how they endure to this day.

The period between 1901 and 2000 was very prolific in terms of vaccine research and production. It began with inoculation against tuberculosis (BCG or Bacillus Calmette-Guérin), which was developed between 1905 and 1921 but was not used in mass vaccinations until after World War II.

Immunization against this disease remains important today: globally, it is the 13th leading cause of death overall and the second from infection (after COVID-19). In 2020 alone, it caused the infection of 10 million people and the death of 1.5 million.

Creating the pertussis (whooping cough) vaccine took years and required the efforts of several researchers. It culminated in production in the 1930s. Then improvements came in the 1980s and 2000s.

Today, this disease is one of the main causes of death preventable by vaccination. The majority of deaths occur in unvaccinated young children or with incomplete vaccination (ie, without the necessary three doses). 

In the 1960s, two vaccines against poliomyelitis or infantile paralysis were developed: an injectable one based on the dead virus, by Jonas Salk, and an oral one based on the live virus, created by Albert Sabin. None was patented. Through these inventions, and with inoculation campaigns, the eradication of the disease was achieved throughout the world except in Pakistan and Afghanistan.

A great figure of this period was Maurice Hilleman, an American microbiologist with a record number of vaccines to his name – more than 40. Thanks to him and his team, millions and millions of lives have been saved in the fight against measles, mumps, chicken pox, hepatitis A and B, meningitis, pneumonia, Haemophilus influenzae bacteria, rubella and more.

Other achievements of the 20th century included vaccinations against yellow fever, typhus, influenza, and Lyme disease. Adding improvements in research and production, as well as more robust regulations, the 21st century has seen advances against Human Papillomavirus (HPV), Hepatitis C, Influenza A (H1N1), Ebola and, of course, COVID. -19.

Without a doubt, the world has come a long way to get here. From pulverizing scabs from sick people to observing milking cows, injecting chickens in a laboratory, and breaking records developing vaccines during a pandemic, humanity has made incredible progress. But something has remained the same. The goal has always been the same: save lives.


The ‘experimental stable’ of the BCG vaccine: safety, efficacy, proof, and standards, 1921-1933, PubMed.gov, October 26, 2005

Tuberculosis, WHO, October 14, 2021

Tuberculosis, Wikipedia, April 26, 2022

Whooping cough, Wikipedia, April 26, 2022

Pertussis vaccine, Wikipedia, April 22, 2022

Polio, Wikipedia, April 13, 2022

How Much Money Did Jonas Salk Potentially Forfeit By Not Patenting The Polio Vaccine?, Forbes, August 9, 2012

Polio Eradication, Wikipedia, April 20, 2022

Maurice Hilleman, National Center for Biotechnology Information, April 30, 2005

Maurice Hilleman, Nature Medicine, April 2005

Maurice Hilleman, Wikipedia, April 27, 2022

The COVID-19 Vaccine Rollout Was the Fastest in Global History, but Low-Income Countries Were Left Behind, CGD, February 9, 2022

Vaccine, Wikipedia, March 30, 2022

Timeline, The History of Vaccines, Date not specified

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