Outbreak! Plagues That Changed History (5 page)

Inoculation was also called variolization, from
variola,
the official European term for smallpox.
Variola
was derived from the Latin
varius
(“spotted”) or
varus
(“pimple”). It came to be called “the small pox” to distinguish the disease from the symptoms of “the great pox,” a very different illness that appeared in Europe soon after Columbus returned from the New World. We call that disease syphilis.

The variola virus

Effective European efforts to prevent smallpox started in 1717 when Lady Mary Wortley Montagu, a smallpox survivor, learned about inoculation in Turkey. She called the procedure ingrafting. Later, it came to be called variolization. In 1718, Montagu had
her son inoculated. In 1721, she returned to England and had her daughter inoculated. They survived and were proved immune. But British leaders resisted. Male doctors scoffed at a woman’s medical suggestion. Religious officials worried that without disease as a whip, people wouldn’t fear God. It took successful experimentation on prisoners and orphans and acceptance by Montagu’s friends in the British royal family to popularize inoculation. Meanwhile, on the other side of the Atlantic, Reverend Cotton Mather learned about the African version of the procedure from his slave Onesimus. Mather introduced variolization to Boston. By the Revolutionary War, George Washington would inoculate the entire Continental army.

The epochal year in smallpox prevention, however, was 1796, when British doctor Edward Jenner proved that inoculation with the harmless
vaccina
(cowpox) virus prevented infection with smallpox. He called this procedure vaccination. His discovery was published in a pamphlet that was translated into German, French, Spanish, Dutch, Italian, and Latin. Vaccination quickly spread around the world, but it took nearly two more centuries to wipe out the disease. By 1977, a heroic decades-long campaign of global vaccination by the World Health Organization finally broke the last link in the smallpox infection chain. Smallpox was eradicated from the wild. The virus still exists, though it is confined to a freezer. Two, actually: one in the United States, the other in Russia.

Survivors of certain infectious diseases are invulnerable to repeat epidemics. This immunity gives them the ultimate advantage. When the illness returns, they will remain healthy while others sicken and die. This difference between the immune and susceptible has sometimes had historically significant consequences. In the case of yellow fever, the significance was truly awesome: it helped bring an end to New World slavery.

In the sixteenth century, Europe had conquered the Aztecs, the Incas, and the indigenous people of the Caribbean and much of Amazonia and eastern North America. The New World seemed an inexhaustible supply of wealth: land for the taking, gold and silver from its mines, food from its farms, hides, feathers, pelts, wood, and dyes from its forests. Most importantly, the New World was an astonishingly fertile place to plant a valuable Old World crop: sugar. Sugar plantations needed a source of plentiful, cheap workers—preferably slaves. Europe itself wouldn’t do; the continent was still underpopulated from the Black Death. With demand for labor exceeding supply, peasants had power: wages were going up. Nor was the New World a potential slave-labor pool, for European depredation and disease had nearly wiped out the Native American population.

The obvious alternative was Africa, a continent European explorers and colonists were just beginning to exploit. Africa already had a bustling slave trade to satisfy local and Muslim demand. The Europeans simply redirected the flow across the Atlantic and opened the spigot full blast. The deadly irony of this choice would become apparent too late. Along with the estimated twenty million Africans enslaved and shipped to America for European greed came yellow fever, an African disease to which most slaves were immune but slave owners were not. The illness would prove to be slavery’s undoing, first in the Caribbean, then in North and South America. Later, the disease would also play an important role in the United States’ efforts to project its power throughout the region.

Human beings have lived in Africa longer than on any other continent. Pathogens that live there too have become exquisitely adapted to exploiting us. Malaria, yellow fever, river blindness, and elephantiasis are just a few of the diseases that coevolved with people, fine-tuning their life cycles to our own. Thousands of years ago, when many of our ancestors left Africa to populate temperate regions, they managed to leave many of these parasites behind. But when Europeans returned to conquer Africa, the microbes were waiting. In West Africa, tropical diseases killed so many Europeans the region was nicknamed “the white man’s grave.” Within a year of arrival, most would-be conquerors weren’t running plantations or sipping gin on the veranda, they were composting in
the soil. The image of the European explorer or missionary dying in his tent from some tropical illness was so common it became a literary cliché. “Beware, beware the Bight of Benin,” warned one British rhyme about West Africa. “One comes out where fifty went in.”

Yellow fever proved an exceptionally portable African disease. On ships leaving Africa for the New World, the fever would usually strike a week or so into the voyage. Mild cases would feel like the flu: the symptoms would pass and the host would recover. In severe cases, however, the illness would progress from fever, blinding headaches, chills, and intense muscle pain to bleeding from the nose and mouth. Blood would collect in the stomach, coagulate and darken, and exit as yellow fever’s unmistakable black vomit. Eventually the liver would fail, turning the skin a jaundiced yellow. Death would follow.

Yellow fever scythed through ship after ship sailing from Africa to the New World. Sometimes entire crews perished from yellow fever. On average, one-fifth were done in. When a fever-struck ship arrived in port, it was often quarantined and forced to fly a yellow flag or “jack.” Yellow jack became the English maritime name for the disease. As with other mysterious illnesses, Europeans tried fervent prayer and the usual Galenic cures: bleeding, purgatives, enemas, cold-water baths, or aromatic talismans to ward off the miasmas thought to cause the disease. As usual, nothing worked.

Yellow fever would often break out on slave ships at sea, sickening and killing the European crew. Adult Africans who had survived the disease as children were immune, a black invulnerability whites found mystifying.

Almost as mysterious as yellow fever itself was the fact that enslaved Africans seemed invulnerable to the illness. This was a powerful advantage. When white slavers sickened, blacks could revolt. The famous slave mutiny aboard the ship
Amistad,
for example, was probably made possible by yellow fever. Later, when the disease ravaged Europeans running the plantations of the New World, Africans had multiple opportunities to escape, resist, or attack their tormentors.

How to explain this difference between the races? Whites didn’t understand that blacks, having survived yellow fever in Africa as children, now enjoyed life-long immunity to the disease. Instead, the same people who had once concluded that Native Americans were inferior because they died from European disease now assured themselves that blacks were suited to slavery because they were immune to yellow fever. The logic of bigotry is a marvelously malleable thing.

Yellow fever repeatedly harassed European efforts to exploit the Americas. The illness effectively closed the Amazonian basin to European exploitation and repeatedly devastated the plantation economy of the southern United States. (Remarkably, though ships also traveled from Africa to Asia, yellow fever never took hold there.)

One of the earliest New World yellow fever outbreaks was on the British Caribbean island of Barbados. This efficient sugar machine was ravaged by yellow fever from 1647 to 1650 and again in 1690, with over 10,000 people killed.

Even more profitable and more deadly was the French slave colony of Haiti (then called Saint Domingue) on the island of Hispaniola. It is hard to believe that what is now the poorest, most environmentally devastated place in the Western Hemisphere was once the most lucrative colony in the world. Haiti produced more sugar than all the other Caribbean islands combined. It made more money for France than England’s revenues from all thirteen American colonies. But in 1789, the French Revolution toppled the monarchy. Ideas of “Liberté! Fraternité! Egalité!” filtered to Haiti. By this time, so many Africans had been imported to the island that slaves now outnumbered their white masters fifteen to one. In 1791, Haiti’s slaves revolted. Hundreds of thousands rose up, torched cities, burned plantations, and massacred whites. In 1794, France’s revolutionary government abolished slavery throughout the colonies. In 1802, however, France’s new ruler, Napoleon Bonaparte, tried to reassert control of Haiti and reestablish slavery. He envisioned an even more profitable colony, supplied with food from France’s Louisiana Territory. Napoleon sent a massive amphibious force commanded by his brother-in-law, General Charles leClerc. The soldiers managed to kill over 150,000 slaves. But 50,000 French soldiers also died (including leClerc), mostly from yellow fever.

Imagine trying to fight an enemy impervious to an invisible force that made your comrades become feverish and jaundiced, spew black vomit, and die. The French could sustain neither their morale nor the
invasion. Napoleon went on to acknowledge an independent Haiti, and in 1803 sold France’s claim to the now apparently useless Louisiana Territory to the United States.

After the African slaves of Haiti revolted and massacred their French masters, Napoleon Bonaparte tried to reassert control. In 1803, his massive amphibious force was defeated. Some 50,000 French soldiers died, mostly from yellow fever.