As we line up for our flu shots this year, it’s worth remembering that influenza is only one of about 30 diseases that once terrorized our ancestors but are now largely preventable with vaccination. Though we take them for granted, most vaccines—such as the flu shot, developed in 1945—are recent inventions. In fact, it was just 50 years ago that the World Health Assembly embarked on a global campaign to eradicate smallpox. It’s also been only 30 years since that effort’s success and since the United States’ last case of polio caused by a “wild” virus.
The idea that survivors of some diseases couldn’t become ill again—and that they might pass this immunity on to others—has a long history. In 430 BC, Thucydides observed of a plague that swept Athens, “No one was ever attacked a second time.” China and India tried forms of vaccination hundreds of years before the Western world’s modern attempts. Women from the Caucasus, prized for their beauty, were inoculated (from the Latin for “to graft”) with matter from smallpox pustules in places on their bodies where the resulting scars wouldn’t be noticed (assuming they survived). Circassian traders brought this process, also called variolation, to the Ottoman Empire in 1670.
There it came to the attention of one of the first heroes of immunization, Lady Mary Wortley Montagu, wife of the British ambassador in Istanbul. Smallpox had already killed her young brother and severely scarred her beautiful face. When Montagu learned about variolation at the Ottoman court in 1718, she ordered the embassy surgeon to inoculate her 5-year-old son. Later, she had her 4-year-old daughter inoculated in the presence of the royal physicians back home in England.
Boosted by Lady Montagu, variolation soon became popular. Though the procedure had risks, the fatality rate was only one-tenth that of naturally occurring smallpox. In 1721, variolation reached the Americas, where the Rev. Cotton Mather advocated it during a smallpox epidemic that infected half of Boston. Mather carefully documented the lower mortality rate among the inoculated, but the procedure was controversial, and the reverend’s house was firebombed.
In 1757, 8-year-old Edward Jenner was inoculated with smallpox in Berkeley, Gloucester, England. He survived the resulting mild case of the disease and, a few years later, at age 13, was apprenticed to a country surgeon and apothecary in Sodbury—where Jenner first got a glimmer of a better way to prevent smallpox. He overheard a milkmaid say, “I shall never have smallpox for I have had cowpox. I shall never have an ugly pockmarked face.”
It had long been legend that milkmaids were immune to smallpox, perhaps because of catching the milder form of the disease, which affected cattle. Even before Jenner famously put this idea to the test, Benjamin Jesty had experimented with such an inoculation. But Jenner was the first to scientifically attempt to stop the spread of disease by vaccination.
On May 14, 1796, he took matter from the fresh cowpox lesions on a young milkmaid, Sarah Nelms, and inoculated 8-year-old James Phipps. In July, Jenner inoculated the boy again, this time with smallpox; no disease developed.
Jenner coined the term vaccination for his new process, from the Latin for cow, vacca. A Harvard physics professor, Benjamin Waterhouse, and Thomas Jefferson experimented with vaccination in Virginia in 1880; Jefferson went on to establish the National Vaccine Institute to implement a nationwide program.
Smallpox, which had killed 400,000 people annually in 18th-century Europe, claimed its last victim in 1977 in Somalia, and was declared eradicated in 1979. Louis Pasteur built on Jenner’s work, developing a rabies vaccine in 1885. Subsequent vaccines began to conquer one scourge of humanity after another—plague, cholera, diphtheria, pertussis and, in 1921, tuberculosis, which had killed Jenner’s wife, oldest son and two sisters.
But protection remained elusive against poliomyelitis, which infected 60,000 Americans—mostly children—in 1952 alone. Reminiscent of the twin approaches to smallpox, there were two schools of thought in regards to a polio vaccine: Dr. Jonas Salk used a killed virus, while Dr. Albert Sabin argued for a weakened live virus.
Working at the University of Pittsburgh, Salk—who helped create the influenza vaccine—succeeded first. Preliminary tests in 1952 were promising enough for the National Infantile Paralysis Foundation to undertake a massive clinical trial in 1954. Each of the 1.8 million grade-schoolers who participated, only about one-third of whom got the actual vaccine, received a piece of candy and a “Polio Pioneer” card. When the results were announced April 12, 1955—the vaccine was “safe, effective and potent”—church bells rang across the nation.
Sabin’s rival approach, which led to an oral vaccine in 1962, ultimately superseded Salk’s vaccine in the global fight against polio. Because the live virus can sometimes cause the actual disease, however, the United States has returned to the Salk strategy of using killed viruses.
Today, immunologists continue the battle against infectious diseases, with efforts to develop new vaccines for viruses ranging from HIV to “swine flu.” Ironically, the vaccines our ancestors heralded as miracles are increasingly forsworn for religious reasons or fears of side effects. Arthur Allen, author of Vaccine: The Controversial Story of Medicine’s Greatest Lifesaver, has written, “As infectious diseases disappeared, in part thanks to vaccines, the risks of vaccination itself were thrown into relief.”
In recent years, various vaccine fears have led to resurgences of diphtheria in Russia and polio in Nigeria. In the first half of 2008, the US Centers for Disease Control received reports of 131 measles cases—the highest number since 1996; more than 90 percent of those infected apparently hadn’t been vaccinated.
If there’s anything positive about the latest flu scare, perhaps it’s to make us appreciate anew the medical miracle of “getting a shot.”
The flu shot, first developed in 1945, is the only vaccine that must be updated every year, to account for ever-evolving strains of influenza. The flu virus itself wasn’t identified until the early 1930s. Epidemiologists today estimate the 1918 influenza killed as many as 100 million people worldwide—more lives than the Black Death claimed in the Middle Ages. Some historians believe more soldiers died from the flu than in all the battles of World War I.
Yet, as John M. Barry writes in The Great Influenza (Penguin), the flu pandemic also helped revolutionize US medical science: “As late as 1900, it was more difficult to get into a respectable American college than into an American medical school. At least 100 US medical schools would accept any man—but not woman—willing to pay tuition; at most 20 percent of the schools required even a high-school diploma for admission—much less any academic training in science—and only a single medical school required its students to have a college degree.”
The 1918 flu challenged a new breed of medical scientists and, Barry writes, “The scientific knowledge that ultimately came out of the influenza pandemic pointed directly—and still points—to much that lies in medicine’s future.”
1670 Traders bring inoculation to Turkey
1796 Edward Jenner tests first smallpox vaccine
1885 Louis Pasteur develops rabies vaccine
1897 Plague vaccine invented
1917 Cholera vaccine invented
1918 Great flu pandemic infects 500 million worldwide
1921 First tuberculosis vaccine tested
1923 Diphtheria vaccine released
1926 Pertussis vaccine released
1935 Yellow fever vaccine released
1945 First influenza vaccine released
1952 Jonas Salk tests polio vaccine
1955 Salk vaccine declared safe and effective
1959 World Health Authority calls for smallpox eradication
1962 Albert Sabin releases oral polio vaccine
1964 US rubella epidemic infects 12.5 million
1968 Reusable bifurcated hypodermic needle invented
1971 “MMR” (measles, mumps, rubella) vaccine released
1980 Smallpox eradicated
2003 Measles no longer endemic in US
2005 Rubella no longer endemic in US
From the December 2009 Family Tree Magazine