Imagine if you will, a world in which 1 child in 3 or 4 does not survive infancy. A world in which one-half of children or more do not reach their 21st birthday. A world in which the average life span is in the 30s.
That world was reality not so very long ago. In the late 19th century, when my grandparents were born, the average life span in the UK, then one of the most advanced countries in the world, was still only in the 40s. Both my grandmothers died at age 42. None of my grandparents lived to see me (not that that would have been the highlight of their lives).
Human longevity began increasing slowly in the late 18th century, then increased rapidly during the 20th century, despite devastating world wars and the worst pandemic in modern times.
The developments that made this increase possible were many: improvements in food production, sanitation, housing, personal hygiene, and medicine. In the world of medicine, antisepsis (from the 1840s) antibiotics (from 1940s), and numerous pharmaceutical and surgical advances all contributed to the increase in longevity.
But I would argue that the most important medical breakthrough has been the development of vaccines. The first vaccine was that for smallpox, generally credited to Edward Jenner, an English physician, who announced his discovery to the world in 1796.
At that time smallpox was perhaps the most feared disease plaguing the world. Mortality often exceeded 20 percent of those infected, compared to about 1 percent for Covid19. Survivors could suffer long-term impairment: often a pock-marked face, sometimes a loss of sight or hearing.
Jenner (or a friend of his) also gave us the words "vaccine" and "vaccination." They derive from the Latin for "cow" -- vacca. Why "cow"? you may ask. His vaccine consisted of cowpox matter, a milder but related disease once common in cows.
Jenner's vaccine has a backstory. He was not the first to use cowpox matter to prevent smallpox. An English farmer, Benjamin Jesty, had used it about twenty years before. But Jesty did not publicize it. Jenner did, and reaped a fortune.
A different method of smallpox prevention was widely used in parts of the world before Jenner's discovery. Inoculation, as it came to be known, involved purposely infecting healthy people with smallpox matter from the pustules.
Ordinary folk in China, Africa, and the Ottoman Empire had used some variety of the procedure for some time before knowledge of it came to Western Europe and America in the early 18th century. (See Lady Mary Wortley Montagu and Smallpox Inoculation)
Inoculation was highly controversial. Some opponents rejected it on religious grounds, others from the fear that it could spread the disease. It could also kill. About 1 inoculated person in 100 died.
In contrast, the natural disease often produced a case mortality rate of 20 percent or more. In some populations, mortality approached 80-90 percent.
These facts help explain both the opposition to inoculation and the desire for it. In British North America, where it became common after the 1720s, some communities tried to ban it, but public demand for it was powerful, especially during epidemics, and in some towns general inoculations took place at public expense.
Interestingly, as the American Revolution approached, many colonials demanded inoculation to give them "liberty" from a dread disease, not as an infringement of their freedom.
During the American War for Independence, General Washington ordered the inoculation of all soldiers in the Continental Army, a move that helped secure victory over the British.
The soldiers obeyed Washington's order. In fact, many of them were demanding it, even inoculating themselves when it was still prohibited. Compare that to the attitudes of today's anti-vaxxers.
Twenty years after Washington's directive, news of Jenner's vaccine began to spread around the world. In many countries it became mandatory and free. When my family emigrated to America from the UK in 1952, we had to provide proof of smallpox vaccination to be admitted. I still have a faint imprint of the scar on my left arm.
Eventually, in 1979, the vaccine achieved something unique. The World Health Organization declared that smallpox had been eliminated from the world.
No other vaccine has achieved this yet, although the polio vaccine has nearly eradicated a disease that terrified parents in the early 20th century.
One reason why the smallpox vaccine was so successful is that the causative virus is highly stable. In some types of diseases, notably influenza, the causative organism mutates often.
Vaccines do not always provide complete or lasting immunity. But the array of vaccines science has developed since Jenner has saved hundreds of millions of lives.
Below is a list of some of the main ones, and the year in which each vaccine was first developed or approved (In some cases, more effective vaccines came later):
Cholera -- 1880
Rabies -- 1885
Tetanus -- 1890
Typhoid Fever -- 1896
Bubonic Plague -- 1897
Tuberculosis -- 1921
Diphtheria -- 1923
Scarlet Fever -- 1924
Pertussis (Whooping Cough) -- 1926
Yellow Fever -- 1932
Typhus -- 1937
Influenza -- 1937 (first of many)
Polio -- 1952
Measles -- 1963
Mumps -- 1967
Rubella (German Measles) -- 1970
Pneumonia -- 1977
Meningitis -- 1978
Hepatitis B -- 1981
Chicken Pox -- 1984
Hepatitis A -- 1991
Lyme Disease -- 1998
Human Papillomavirus (Causes Cervical Cancer) -- 2006
Malaria and Dengue Fever -- 2015
Ebola -- 2019
Covid-19 -- 2020
PS. I contracted several of these diseases in my youth because no vaccines yet existed. They included measles, rubella, and chicken pox. I recently had the chicken pox vaccine to prevent shingles, a painful disorder that often attacks older people who contracted chicken pox as a child.