The American Plague - Molly Caldwell Crosby [103]
In spite of bubonic plague, malaria and yellow fever, the scientists from both countries made the most of their time in the tropics. They played croquet on the lawn and dined together. They kept gardens with orange bursts of marigold and salmon-colored hibiscus and sun-streaked zinnias. They visited nearby villages in the touring Dodge. But there were a few cultural differences. The Englishmen usually stopped working after 4:00 in the afternoon to enjoy cocktails or play golf or tennis. The British, in turn, found the Americans and their penchant for sunshine strange. The Americans were forever bareheaded in the sun or screening their bungalows and blocking the breeze.
A new epidemic spreading among Africans gave Stokes and his partners fresh fever cases to work with. They drew blood from sick humans, storing it in a glass forest of vials and petri dishes in the lab, and injecting it into various lab animals, primarily monkeys. Their conclusions were mixed, and shipments of fresh monkeys and guinea pigs continued to arrive by boat and train at the lab.
The doctors were beginning to lose hope when they heard of a new outbreak of fever in Kpeve, Gold Coast—now Ghana—at the end of June. Much like Walter Reed and his Yellow Fever Commission had done in Cuba, the doctors hunted down the disease wherever outbreaks of fever occurred. Members of the commission traveled the 100 or so miles from Accra to Kpeve to see a European farmer and his wife—both of whom had been diagnosed with typhoid. Instead, they found yellow fever; or perhaps, yellow fever found them.
They also discovered an African man, twenty-eight years old, named Asibi. He was sitting on a stool, his head in his hands, his temperature 103 degrees. Aedes aegypti mosquitoes swarmed around him like sparks rising from a flame. The doctors took blood samples from several of the patients, including Asibi, and returned to their lab in Accra.
Asibi’s blood was injected into a marmoset, two guinea pigs and a monkey with the affectionate name Rhesus 253-A. The rhesus monkey arrived in a shipment from Asia; the doctors had discovered that African Old World monkeys seemed immune to the fever. Rhesus 253-A was the color of sand, with round, black eyes and a face like a human child. It was a lively, chattering monkey until it became ill a few days later. It grew quiet in its cage and soon died. Stokes autopsied the animal and found all the postmortem signs of yellow fever. It was their first major breakthrough. The doctors bled the monkey and injected the loaded blood into another monkey, Rhesus 253-B, and it too soon died of yellow fever. They passed the infected blood through a Berkefeld filter, and just like James Carroll, found nothing. No known bacteria or parasite had been caught in the filter. Whatever organism infected the blood of the monkeys had to be even smaller.
Mosquitoes fed on the blood of the sick monkeys, then the doctors bound healthy animals to boards, allowing the mosquitoes to bite, passing the virus from one monkey to the next, creating in the lab what nature had been accomplishing for centuries. If yellow fever could be passed effectively to monkeys, the possibilities were endless. Suddenly, the disease began to make more sense. Forest workers often returned from the bush with a case of yellow fever, in spite of the fact that they had not been in contact with any sick humans. If monkeys could harbor the virus, then the jungle itself was fueling the yellow fever virus, giving it refuge. It explained how endemic yellow fever lives quietly in the jungles, moving through monkey populations before exploding on urban, human ones. By 1935, an American doctor named Fred L. Soper would discover that monkeys also acted as hosts to the disease and that other mosquitoes could carry the virus as well. It became known as jungle yellow fever.
The discovery that the West Africa team had found a filterable virus passing through monkeys was met with controversy— particularly