Intended for healthcare professionals

Medical Milestones

Vaccines: conquering untreatable diseases

BMJ 2007; 334 doi: (Published 04 January 2007) Cite this as: BMJ 2007;334:s19
  1. Michael Worboys, director
  1. 1Centre for the History of Science, Technology and Medicine and Wellcome Unit for the History of Medicine, University of Manchester, Manchester M13 9PL

    Vaccines have saved tens of millions of lives. All modern innovations can be traced back to Pasteur's 1885 breakthrough with rabies vaccine

    Louis Pasteur's introduction in July 1885 of a rabies vaccine that contained a laboratory attenuated live virus deserves the title of the greatest medical milestone for three reasons. First and foremost, Pasteur's innovation introduced the laboratory modification of micro-organisms by attenuation, to render them less pathogenic but still immunogenic. Vaccines have saved hundreds of millions of lives and spared generations the suffering and long term consequences of infections. These numbers continue to grow, as researchers—in disciplines such as bacteriology, virology, and immunology, which Pasteur effectively founded—improve the number, effectiveness, and delivery of vaccines.

    Although this reason alone would make Pasteur's work the leading medical milestone, two other reasons make the case for vaccines unanswerable. Pasteur's rabies treatment was the world's first medical breakthrough to be recognised and celebrated in the public domain. Pasteur was hailed in the press as a great benefactor of humanity and to have opened a new era in medicine. Finally, his high profile and the support he gained garnered funds to establish the Pasteur Institute in Paris, the world's first purpose built medical research institute and the model for others that were established soon after, such as the Robert Koch Institute in Berlin, which opened in 1891, and what became the Lister Institute, opened in London in 1893.

    Milkmaids and cows, children and dogs

    It can be argued that the breakthrough with vaccines actually occurred a century earlier, with Edward Jenner's introduction of vaccination against smallpox in 1796. Jenner was a country doctor in Gloucestershire who had noticed that patients, especially milkmaids, who had suffered from cowpox (also known as vaccinia) were subsequently immune to the deadly smallpox. He first trialled and then promoted inoculation with small doses of vaccinia pustules, which he assumed carried the poison, as a preventive measure—terming the inoculation “vaccine.” Although it attracted much scepticism, news of Jenner's innovation spread rapidly round the world, and travelling doctors took vaccine to the colonies and other countries. Smallpox was greatly feared, and it seemed miraculous that so many thousands of lives could be saved; indeed, such was the standing of “vaccine” that Pasteur named his own methods after it. However, Jenner's innovation was a one-off, and subsequent attempts at emulation, such as inoculating material from syphilis sores to treat infection, failed. By comparison Pasteur's breakthrough was grounded in knowledge and techniques that have been the basis for all the vaccines we have today.

    Pasteur, who was not a doctor, shifted his attention from vaccines for anthrax, sheep pox, and rabies in animals to those for human disease, because of medical interest in the new microbiology and because of the possibility, in the case of rabies, of building up immunity during the long incubation period. Pasteur announced his breakthrough in October 1885, giving graphic accounts of the cases of two children, savagely bitten by rabid dogs, who faced certain death until treated in his clinic. Medically, an untreatable disease had been conquered. Such was the excitement this generated that some doctors and scientists immediately looked to the eradication of major communicable diseases. At this moment all things seemed possible for medicine, and the next decade seemed to prove this. Frightening killer diseases could be cured, as Pasteur's coworkers contributed to the development of antitoxic sera for diphtheria and tetanus; but they could also be prevented, as protective vaccines using inactivated micro-organisms were developed against cholera, typhoid fever, and the plague.

    In the 20th century vaccines for many more bacterial and viral infections were introduced. To imagine a world without vaccines is to imagine a world threatened with smallpox, which was eradicated in the 1970s largely through vaccination campaigns. In the United Kingdom today only older generations will remember the predations of childhood diseases made rare by jabs now taken for granted: diphtheria (1923), whooping cough (1926), measles (1963), rubella (1969), polio (1958 and 1961), and measles, mumps, and rubella (1969). For example, from 1920 to 1940 between 40 000 and 70 000 cases of diphtheria were notified each year in the UK, but by the 1990s the number was around 10 a year. In the 1950s as many as 7500 cases of polio were reported in a year; in the whole of the 1980s there were only 25. The incidence of tuberculosis—the principal cause of death in adults a century ago—was reduced by the BCG vaccination, introduced in 1927. Many elderly people now receive annual flu shots, as do high risk workers, who also receive hepatitis A and B vaccines. And would we have the same confidence about overseas travel without yellow fever jabs or modern versions of the vaccines introduced in the 1890s?

    New delivery systems and new targets

    There is no reason to suppose that the future of vaccines will be any less remarkable than their past. The greatest benefit to humanity would be for all current vaccines to be made available in all countries and to all groups across the world. Greater diffusion should be aided by new delivery systems—aerosols and skin patches—and by the move away from vaccines that need cold storage. Molecular biology means that we can look forward to preventive and therapeutic vaccines for common infections such as those from staphylococci and pneumococci, for parasitic diseases such as malaria and schistosomiasis, for recent infections such as HIV, viral haemorrhagic fever, and severe acute respiratory syndrome, for autoimmune diseases, and even for infective cancers. Indeed, a vaccine against human papillomavirus and thus against cervical cancer was approved very recently and could be seen as a medical milestone in its own right.

    Although Pasteur brought the great benefits of medical innovation to the public's attention and pioneered the institutionalisation of medical research, it is because of the present and future potential for vaccines to save lives and prevent suffering that we can consider his 1885 discovery to be the greatest medical milestone.


    • Publication of this online supplement is made possible by an educational grant from AstraZeneca

    • Competing interests: None declared.