In the cities of the United States in the nineteenth century, the only end to the cycle was frost. Then the mosquito larvae stopped hatching, and the disease could no longer be transmitted. The following spring there would be more mosquitoes but no infected blood to feed on, so everyone was safe—until someone incubating yellow fever showed up again. That was especially likely in the hot, moist Southern summers that were so good for breeding mosquitoes. Especially in New Orleans, from which infected travelers often left for the interior regions of the country.

Memphis did not know this in 1878. The mosquito’s role would not be proved until 1900, although a Southern doctor, Josiah Nott, guessed at it in 1848. And the importance of viruses was not even clearly understood until well into this century.

What Memphis did know was that yellow fever meant, in most cases, a horrible death. The first symptoms were chills, constipation, nausea, severe pains in the head and back, and high fever. After anywhere from a few hours to a few days, the temperature subsided. This was the turning point. A lucky minority slowly recovered and were thereafter immune; for the rest, the fever would suddenly return, while the skin and whites of the eyes yellowed with jaundice. There would be internal hemorrhages, especially in the stomach. Soon the sufferer would retch up a dark mixture of mucus, blood, and digestive juices—the dreaded black vomit that gave the affliction the name of vomito negro among Latins. Delirious, puking, and pouring sweat, the victim died in agony and stench. And before the body had cooled, the disease was fireballing through the neighborhood.

DOCTORS DISAGREED about the cause of this spread. The best professional opinion was that the “spores” or “seeds” of the illness were somehow carried in a “miasma,” that is, in bad air—especially bad air arising from marshy and swampy ground. But others believed that the infection was transmitted through “fomites”—the excretions of the patients, their soiled and stinking bed-clothes and bedding, their dishes, towels, toilet articles, or anything they had touched.

The best professional opinion held that the “spores” or “seeds” of the illness were somehow carried in a “miasma,” or bad air.

There was disagreement, too, about what started the fever. “Contagionists” believed (correctly, but for the wrong reasons) that it was brought in by an already sick outsider, so quarantine was a defense. But there were “anticontagionists,” who argued that the fever could start spontaneously in many towns at once. Honest doctors on both sides admitted their uncertainty. As one Memphian later put it, the disease was a “law unto itself in its tenacity of life as well as in its inception, growth, and progress.”

Memphis’s experience with yellow fever grew progressively worse after its 1855 encounter. An outbreak in 1867 took at least 250 lives. And in 1873 the city was very, very badly hit. Memphis was especially vulnerable in a public health sense, and there were circumstances that put a powerful kick into the social as well as medical consequences of an epidemic.

To start with, there was the city’s social geography. The Irish, mostly domestic servants and laborers, lived in crowded districts with names like “Pinchgut” and “Boxtown,” huddled near the riverbank. There they shared alleys with other poor newcomers, black and white. More affluent Memphians were already moving up the bluffs and eastward onto the high ground, away from the brawling, drinking, and crime of the riverfront.

These richer Memphians were disturbed by more than merely the turbulence of the unwashed. Memphis was just emerging from Reconstruction, which had temporarily put a new group into power. Expensive improvements had been undertaken. Many were necessary, but there had been widespread corruption. By 1878 there was a heavy municipal debt—between $4,000,000 and $6,000,000. Most of the tax burden fell on the professional and mercantile classes. They felt plundered and believed themselves helpless to deal with the situation as long as they were outvoted by the more numerous Irish, so they banded together in a conservative movement, demanding that the city’s charter be repealed and that Memphis be ruled by commissioners chosen by the governor with the consent of the Senate. As they frankly admitted, their problem was too much democracy—“We have in our midst a large and controlling voting element which has but little at stake in the welfare of our city”—and their purpose was to get Memphis and its business future “away from the popular elections of the times and from all partisan influences.”