Before vaccination, there was inoculation, a process of producing immunity by introducing an infectious agent onto abraded skin or a mucus membrane. Inoculation was used for thousands of years across many cultures to prevent smallpox, a disfiguring and sometimes deadly disease.
Several accounts describe smallpox inoculation as practiced in China and India in the 1500s. It is difficult to pinpoint when the practice began, as some sources claim it dates back as early as 200 BCE.
17th century Chinese Emperor K’ang, survived a case of smallpox, and then wrote about inoculation in a letter to his descendants:
“…I had it used upon you, my sons and daughters, and you all passed through the smallpox in the happiest possible manner…. In the beginning, when I had it tested on one or two people, some old women taxed me with extravagance, and spoke very strongly against inoculation. The courage which I summoned up to insist on its practice has saved the lives and health of millions of men. This is an extremely important thing, of which I am very proud.”
The method used during K’ang’s time involved grinding up smallpox scabs and blowing the dust into a person’s nostril.
Africa & America
In 1721, a ship arrived in Boston from the West Indies with smallpox on board, and despite precautions, a full-blown epidemic started that infected roughly half of the town’s 11,000 residents. An African-born enslaved man named Onesimus, shared his experience with Cotton Mather, the town’s problematic leading minister and Onesimus’ legal owner. When Mather asked Onesimus if he’d ever had smallpox, he answered “yes and no,” explaining that he had been inoculated in his home country and was now immune to the disease, “people take juice of smallpox and cut the skin and put in a drop.”
Mather interviewed other African-born men and realized that those who had been inoculated were immune to the epidemic currently raging in Boston. Mather pursued a determined course of action, asking doctors to inoculate their patients and the town’s ministers to support the plan. Boston still suffered dreadfully, but thanks to information about a practice dating back untold generations, from people enslaved by white landowners, the terror linked to smallpox began to recede.
Stories of the success of inoculation in New England spread to England and in the 1790s physician Edward Jenner noticed that milkmaids in his community generally didn’t become sick with smallpox. He guessed it was because they were often exposed to cowpox, a related disease in cattle that only caused mild illness in humans.
In May of 1796, Jenner inoculated an eight-year-old boy with matter from a cowpox sore on the hand of a milkmaid named Sarah Nelmes. The boy suffered a small rash and felt ill for several days but made a full recovery. In July, Jenner inoculated the boy again, this time with matter taken from a fresh human smallpox sore, to test his immunity. The boy remained healthy.
Jenner published a pamphlet which outlined his success in protecting 23 patients from smallpox infection with material from a cowpox pustule. In fact, the word “vaccine” was coined by Jenner; derived from Variolae vaccinae (Latin for ‘smallpox of the cow’). Even though Jenner used the scratching method to introduce infectious material to his patients, ‘vaccination’ was adopted later as the term for the practice of inoculation by injection with a needle that we use today.
Fast forwarding to 1960, messenger RNA (mRNA) was discovered as the cell’s means to encode information needed to fight infections. In late 1987, Robert Malone, a graduate student at the Salk Institute for Biological Studies, mixed strands of mRNA with droplets of human fat. The human cells absorbed the mRNA and began producing proteins. Realizing that this discovery might have far-reaching potential in medicine, Malone thought it might be possible to “treat RNA as a drug”.
Since 2010, mRNA vaccines have been studied for influenza, Zika, rabies, and other diseases in animals and humans. Recent technological advancements improved mRNA vaccines’ stability and effectiveness enough for scientists and drug manufacturers to recommend their use for the first time outside of the research lab in the fight against COVID-19.
Currently vaccines for COVID-19, are the only approved mRNA vaccines. They use mRNA that directs cells to produce copies of a “spike protein” on the outside of the coronavirus. Once replicated, the immune system detects the spike protein and creates an immune response to prevent the disease. If the immunized person is exposed to COVID-19, they are less likely to become seriously ill or die from the disease. Researchers are studying how mRNA might be used to develop vaccines for additional infectious diseases and continue the life-saving legacy of vaccination.
Vaccines to Keep You and Your Community Safe this Winter
Aside from the COVID-19 vaccines now available through the miracle of modern science, there are two other vaccinations we can get to help keep ourselves and our community safe. Flu vaccines protect against the four influenza viruses that research indicates to be most common. Everyone 6 months of age and older should get a flu shot every season with rare exception. A study just this year showed that among adults, flu shots were associated with a 26% lower risk of ICU admission and a 31% lower risk of death from flu compared with the unvaccinated.
Pneumococcal disease is another serious illness that is caused by bacteria called pneumococcus. In adults the disease can cause pneumonia, blood infections, meningitis, and is sometimes deadly. Pneumovax is a vaccine that protects against 23 types of pneumococcal bacteria. The CDC recommends annual vaccination for all adults 65 years or older and for adults 19 years or older who smoke or have an immunocompromising condition.
If everyone who has been vaccinated for COVID-19 received flu shots and Pneumovax this year as well, countless hospitalizations and deaths could be avoided. Making vaccination a regular part of your health care can prevent future pandemics and save lives.
Volume 6 of Science and Civilisation in China by Joseph Needham
The Life and Death of Smallpox by Ian and Jenifer Glynn
“How an African slave helped Boston fight smallpox” from The Boston Globe:
Timeline of vaccination history