Called “the most dreadful scourge of the human species,” smallpox begins with fever, muscle pain, headache, and fatigue. Days later lesions will appear first inside the mouth and on the tongue, and later, lesions will attack the skin on forehead, face, trunk, and arms.

By days six or seven, each lesion swells into a pustule, a painful pocket that drains fluid, hence the name “pock[et]s” or pox.

During an endemic, mortality rates will exceed 30%. Of those who live, a percentage are blinded, but all who live will suffer from hideous facial scars. For example, George Washington contracted smallpox, lived through the ordeal, retained his eyesight, but was scarred for the rest of his days.

For millennium, there was no cure among English-speaking people, until Lady Mary Wortley Montagu learned of variolation, when she and her husband lived in Istanbul.

She watched as a physician there would draw fluid from an infected man or woman’s poxes, and then introduce them into a series of scratches on an uninfected person’s upper arm.

The resulting smallpox was not as lethal as the normal disease, but a percentage were struck blind, some endured fever and fatigue, some had poxes on face and chest, and some died.

Also, once a person was variolated, he or she was infected with smallpox and could pass on the disease to others. Doctors quarantined variolated people, until they no longer displayed any symptoms.

In 1754, a five-year-old English boy named Edward Jenner was carted off to a crude smallpox clinic, where he received variolation, but he then endured weeks without proper food, no friendly faces, no contact with family, and few comforts. Weeks later his relatives took him home.

Once Jenner had more or less recovered, he pursued an education in the sciences. At St. George’s Hospital in London, he studied medicine, and there he decided he would practice surgery back in Berkely, his hometown, in Gloucestershire, west of London.

One day a milkmaid, named Ann, explained to Dr. Jenner that she did not worry about smallpox, because years before she had milked a cow that had poxes on its udder. Ann further explained that days later she noticed lesions on her hands. The lesions then became poxes that healed in a few days.

She told Dr. Jenner, “But I have had cowpox, sir, and I cannot take smallpox.”

Jenner was most curious. He quizzed her again, and learned that she did not ever feel feverish, had experienced no muscle pain, no fatigue, and no facial poxes. Jenner wondered if the cowpox was a milder form of smallpox.

He then jumped to a startling conclusion: he would try variolation but with cowpox.

First, though, he performed variolation with smallpox fluid on five Stoneham Farm milkmaids and herders, those who had cowpox lesions on their hands. None of the five came down with smallpox.

When other doctors in the neighborhood heard of Jenner’s bizarre experiment, they mocked him. At a medical meeting, one doctor glared at Jenner and said, “It would ill behoove us to start inoculating with an animal’s disease, and getting ourselves laughed and sneered at even more.”

Another doctor made a motion to expel Edward Jenner from the medical community, but the vote failed to pass. Jenner decided he must experiment on his own, without his colleagues’ support.

One spring day, Mrs. John Phipps brought her eight-year-old son James to Dr. Jenner’s surgery and insisted that he perform a variolation on James, but use cowpox fluid. Jenner agreed.

On May 14, 1796, Jenner withdrew the discharge from the poxes on the hands of Sarah Nelmes, a milkmaid, and then he passed that same fluid into scratches on both of James Phipps’s upper arms. Days passed. James suffered “a slight chill, fever, and headache, and a few cowpox pustules.”

The town rowdies though gathered around Edward Jenner’s house daily to jeer at him, to ridicule him, to harass his experiments, to threaten to beat him up, but soon, young James Phipps was well.

A delegation from the town came to Dr. Jenner’s home, and told him, “You are wrong in doing this. We feel you are risking the health and well-being of the community. We will find a way to stop you.” Edward Jenner later told his wife, “Ignorance and fear of the new were hard to conquer.”

Years passed, and eventually, the medical profession realized that Jenner’s vaccination, from the Latin word “vacca” for cow, worked, that it was superior to variolation, less lethal to the patient.

In 1840, Parliament forbid any further “variolation” treatments, and in 1853, Parliament made “vaccination” compulsory for all children born in England. This latter law ignited “protest marches and vehement opposition from those who wanted and demanded freedom of choice.”

The last natural-occurring case of smallpox was discovered in October 1977, in Somalia, and today smallpox resides in glass tubes in just two laboratories: the Center for Disease Control in Atlanta, Georgia, and also the VECTOR Lab in Koltsovo, Russia.