Fortunately, one of Maridi’s public health doctors was the son of a powerful local chief, and with the leader’s support the people were eventually coaxed into bringing their dead to Maridi. Francis, Simpson, El Tahir, and Bres would take the bodies a discreet distance away from public view, put on their protective clothing, gloves, and respirators, and remove all undigested food and excreta from the cadavers, as prescribed by tribal custom, which entailed hand removal and manipulation of wastes without evisceration. They would also carefully remove tissue and organ samples for laboratory analysis.
Stopping the funeral cleansings and closing the hospital brought the Maridi epidemic to a halt, so Francis and El Tahir made their way to the even more remote town of N’zara. There Don found Joe McCormick’s boxed note, guiding them through the sequence of original Ebola cases.
“Hi Don,†the note read. “Found your index case.†After providing details, it was signed simply, “Joe.â€
N’zara was the hub for a population of about 20,000 people, most of whom lived in village clusters of mud huts scattered throughout the surrounding savannas and jungle. The economic center of N’zara was a cotton factory, where some 2,000 men made fabric from locally grown cotton using nineteenth-century machines. Inside the factory conditions were harsh; the tin roof magnified the excruciating equatorial heat, lung-damaging cotton fibers filled the air, bats swarmed out of the roofing periodically, filling parts of the factory with their malodorous guano, and the poorly paid men worked long, exhausting shifts.
McCormick’s note explained who had been the first case in the mysterious epidemic and traced the order of subsequent infections. On June 27, well before the apparent onset of the Yambuku epidemic, a man who worked in the N’zara cotton mill fell ill and died on July 6 of hemorrhaging. His death was soon followed by those of two co-workers whose jobs were in the factory’s cloth room, the same site where the first man worked. By July about two factory workers each week contracted the virus. By September several workers and their friends and family members had contracted Ebola, and at least thirty-five had died.
Two-thirds of the subsequent Ebola cases in N’zara involved a man named Ugawa, who was comparatively wealthy because he ran N’zara’s cultural hub, a jazz club. The factory workers would spend much of their earnings in Ugawa’s club, eating, drinking, and buying the sexual favors of the barmaids. Most of N’zara’s epidemic evolved from those liaisons.
And it was Ugawa who had enough money to travel to the Maridi hospital when he came down with the disease. Once his virus got into the Maridi hospital, it spread like wildfire.
By the time the WHO team arrived in N’zara in mid-November, the epidemic was on its way out, having sickened over a third of the Maridi hospital staff, forty-one of whom died. It threw the hospital into chaos, from which many staffers fled. Nearly all the staff that got the disease were infected on the job, primarily through exposure to sick patients’ fluids.
From the staff, the epidemic spread into the community through several generations of transmission. Later investigations would reveal that the N’zara virus was highly contagious, spreading more than eight generations from the index case, as the scientists put it. The Yambuku strain, in contrast, never spread more than four generations. On the other hand, the Yambuku virus was far more likely to kill those it infected.
By November 20 it seemed the epidemic was over, the spread having halted as a result of the hospital closures and changes in funeral practices. Francis totaled up his case list: 284 Ebola cases, 151 deaths, all but four cases occurring in either N’zara or Maridi. As McCormick had suggested in his report to the commission (which Francis could not see in the Sudan), the Sudan virus seemed less deadly. While upward of 90 percent of those infected in the Yambuku outbreak died, only about half (53 percent) of the Sudanese cases were fatal.
The center of Maridi’s epidemic was the hospital, where nearly half of the people hospitalized for other reasons got the disease (93 of 213 patients) and the toll among the medical staff was high.
In N’zara, however, the virus seemed to come, somehow, from the cotton factory, and the WHO team devoted a great deal of time and attention to that building, where nearly a thousand men worked at any given time. Freshly picked cotton came in one end of the structure and was processed room by room into bolts of finished cloth.
Blood tests showed the highest infection and death rates were among the twenty-four men employed in the cloth room: four deaths and five nonlethal cases, for an overall infection rate of 38 percent. Francis and Highton combed the room in search of an animal or insect that carried the Ebola virus. They had no way to test the animals in N’zara, so they were working blind, capturing anything that moved, removing vital organs, and placing them in liquid nitrogen. Eventually, the organs would reach Pat Webb’s lab in Atlanta, where she would perform the tests necessary to determine whether any were Ebola-infected.
They found the cloth room heavily infested with bats, rats, cotton boll weevils, spiders, and numerous other insects. By December, Webb would give the WHO team disturbing news: none of the animal samples contained Ebola virus.
Thus, the origin of N’zara’s epidemic remained a mystery.
Having already spent well over the requested two weeks in the epidemic zone, Francis was anxious to get back to Harvard. The CDC, however, cabled Khartoum to instruct Don to remain in Sudan. It wasn’t until Christmastime that Francis, imbued with a bitterness toward CDC leaders that would color his future activities with the agency, returned to Boston, renegotiated an extension on his CDC leave, and set to work completing his Ph. D. research.
By then, Joe McCormick was back in Sierra Leone, setting up his primitive Lassa laboratory. Karl Johnson had returned to Atlanta. Months later, Pat Webb would get her long-desired taste for exotica fulfilled, when she volunteered to join McCormick’s Lassa studies in Sierra Leone.
Joel Breman did not return to his Michigan Swine Flu work. Instead, he devoted two more years to African research on behalf of the CDC and WHO. He joined efforts to search for cases of monkeypox, a type of virus similar to smallpox that produced illness, but rarely death, in human beings. WHO wanted to be sure that it was safe to cease smallpox immunization efforts; it was essential that Breman find out whether wild monkeys carried forms of pox viruses deadly to humans.20
Throughout the late 1970s and early 1980s human monkeypox case reports would increase steadily, from zero prior to 1970 to 35 in 1983, most occurring in the rain forest regions of Zaire.21 In 1984 some 214 cases would be found in Zaire alone.22
It would turn out that most monkeypox cases occurred in—yes—the Bumba Zone of Zaire in the villages surrounding Yambuku.23 All sorts of animals living in the Bumba-area jungles would be shown to carry monkeypox: tree squirrels, forest monkeys, chimpanzees, and antelopes. But in the end scientists would conclude that the rain forest virus was not genetically close enough to the smallpox virus to pose a threat to human populations, and the monkeypox virus spread so inefficiently from person to person that Homo sapiens epidemics never occurred.24
Breman insisted that the animals and people studied in equatorial Africa during the monkeypox surveys—particularly those surveyed in the Bumba Zone—also be tested for both Ebola and Marburg virus infections. After nearly ten years of testing, no infected animals would be found, although a handful of bats captured in faraway Cameroon would test antibody-positive for prior exposure to Ebola.
The mystery of where Ebola came from would haunt most of those who had been involved in the Yambuku and N’zara investigations for years to come. Guido van der Gröen would spend years working patiently in the highest-security laboratories in the United States, the Soviet Union, and Europe, searching for clues to the origin of Ebola in the virus itself. He was determined to crack the mystery of the organism that he and Karl
Johnson had dubbed the Andromeda Strain.
He would participate in two expeditions back to the Yambuku area in 1979, piggybacking on Bremen’s monkeypox searches, and would test countless animals in search of the natural reservoir of the deadly virus.
In 1980, David Heymann, who was also fixated on the Ebola mystery, would discover that pygmies living in the dense rain forests of Cameroon had antibodies to Ebola, indicating that they had once been infected with the virus. He would corral support from Pat Webb and Guido van der Gröen, and the trio would spend two months living among the Cameroonian pygmies.
The tall white foreigners would find their African counterparts remarkably receptive to the pursuit, willing to use their awesome hunting skills to capture all sorts of creatures for the scientists to test. Van der Gröen would run immunofluorescence tests on over 3,000 animals of 100 different species, ranging from one-meter-long poisonous snakes to chimpanzees.
Webb and Heymann would eventually discover that 15 percent of the pygmies had antibodies to Ebola, proving that whatever animal served as the reservoir of the deadly virus lurked in the dense rain forests of that region. But none of van der Gröen’s meticulously preserved animal samples would be infected.
Still further into the future, Joe McCormick would continue his search, testing animals in the western Ghanaian rain forests. Because it turned out that the natural reservoir of monkeypox was flying tree squirrels, McCormick would capture and test squirrels. And he would find one tree squirrel that had antibodies to Ebola. But it would not be carrying the virus.
The source of both horribly lethal viruses—Marburg and Ebola—remains a complete mystery.
“There is a strong suspicion that the disease is a zoonosis. Monkeys did not seem to play a role in these epidemics and rodents, or bats, may perhaps be the animal reservoir,†stated one of the International Commission’s reports.25 A later WHO official report would bemoan that “since the natural reservoirs of Marburg and Ebola viruses are unknown, no control activities can be carried out in Africa.â€26
Perhaps the bluntest statement appeared in the commission’s second report: “As in the case of Marburg virus, the source of Ebola virus is completely unknown beyond the simple fact that it is African in origin.â€27 But even the assumption that all cases would originate in Africa would prove naive in years to come.
The commission was, however, able to explain how the apparently extremely rare disease spread quickly throughout the Bumba Zone and Maridi. Knowing why a disease spread could allow local authorities to limit future epidemics to a handful of primary cases, preventing hundreds of deaths. El Tahir put it best: “The hospital must be viewed as an epidemic amplifier.†Both in Maridi and in Yambuku the poorly supplied clinics reused syringes hundreds of times a day, injecting drugs from one person to another without sterilizing the needles. McCormick calculated that during the months of September and October 1976, an individual’s odds of getting Ebola virus from a single injection at the Yambuku and Maridi hospitals exceeded 90 percent. Seventy-two of the primary cases in Yambuku (out of 103) were caused by unsterile needles used in the mission hospital. Sureau calculated that 43 percent of the Yambuku-area Ebola victims who got the disease from another person survived the ailment, but only 7.5 percent of those who were injected with contaminated syringes survived.
At the Yambuku Mission Hospital, for example, the commission eventually figured out that the majority of the early Ebola cases involved women who came to see the Sisters for pregnancy-related checkups. When women were questioned, it turned out the real draw to the mission was a miraculous injection that made pregnant women feel energetic and content.
It was vitamin B complex.
The commission determined that injected Ebola infections were far more likely to result in terminal disease than were secondary exposures to sick friends and family members.
The Sisters did not appreciate this information. Still grieving the loss of more than half their staff and colleagues, the missionaries would not countenance accusations that the very individuals who had given their lives in a saintly struggle against an unknown horror should now be labeled agents of epidemic spread.28
X
As Christmas approached, Peter Piot prepared to leave the place that had over two and a half months’ time come to feel like something of a home. He had long since sold the wedding suit and wing tips he wore to Kinshasa. Gone too was his naïve arrogance. In its place was a new sense of confidence coupled with a healthy respect for the microbial world.
“I have seen things which most Europeans only read about in books or see in adventure movies,†he told Sister Genoveva. “My mother, a typical Flemish woman, always taught me, ‘Speaking is silver, silence is gold.’ But I have seen too much to keep my mouth shut.â€
As the Belgian packed crates for his departure, another young adventurer was sitting in Kinshasa, eagerly awaiting his opportunity to go to the Bumba Zone. American CDC scientist David Heymann had volunteered without hesitation to be the last foreign scientist in Yambuku, charged with cleanup epidemiology and, perhaps most important, giving the rest of the crew an opportunity to head home for Christmas.
At Bumba’s airport Heymann and Piot met for the first time, shook hands, and headed off in opposite directions. Years later the pair would work side by side, trying to control another, far larger, deadly epidemic. Piot recognized the excited look in Heymann’s eyes: it was the same look that had filled the now world-weary Belgian’s face when he first arrived so long ago.
As Heymann drove Piot’s Land-Rover along the road to Yambuku, he spotted boys along the way playing with homemade toys. Throughout Southern Africa, boys made clever sculptures of cars and trucks from cast-off wire, and rolled their toy vehicles along the roadside in imitations of the real ones. But Heymann saw these Bumba-area boys all had made something very unusual: helicopters. Nowhere else in Africa had Heymann seen children playing with helicopters. One boy, seeing Heymann’s white face coming down the road, merrily held his helicopter up in the air and then dropped it to the ground, laughing hysterically.
“Wonder what that was about,†Heymann thought.
Back in Bumba, Piot was unknowingly preparing for one more undesired adventure. He glanced angrily at the military pilots who were laughing and guzzling beers with fellow officers while the huge C-130 was loaded. The Bumba quarantine having finally been lifted, hundreds of local traders and still nervous families were clamoring for spots on the huge plane, along with their goats, pigs, monkeys, chickens, and sacks of worldly goods. The task of organizing their boarding was left to Piot, who felt no joy in anticipating another airborne excursion with drunken pilots.
Piot and a few other passengers loaded dozens of crates into the cargo hold, having no idea where it was best to place heavy versus lightweight objects. The anxious pilots left the engines running and occasionally shouted for Piot’s group to hurry. The men placed most of the lighter objects at the front of the plane, heavier crates of laboratory equipment to the rear, leaving the center open for passengers. With the few nets and ropes provided by the pilots the group did their best to secure all the cargo in place.
By the time all the passengers were on board, crammed shoulder to shoulder without benefit of seat belts, or even actual seats, a storm was brewing. The pilots taxied their huge, heavily laden aircraft to the end of Bumba’s tiny tarmac, revved the engines, and roared down the runway. The plane lumbered, groaned, and bounced, unable to gain height with such a heavy load.
“Oh my God!†Piot cried out, seeing the tree line directly ahead. The pilots pulled the throttle sharply, attaining just inches of advantage over the tops of the palm trees. The plane climbed steadily for several minutes until, hitting a pocket of storm turbulence, it suddenly dove a few hundred feet.
The heavy crates to the rear of the aircraft broke loose of th
eir nets, slamming down on the screaming passengers. Blood spattered in all directions, people screamed in pain, and the inebriated pilots responded by jerking the plane up, causing the front-loaded cargo to snap loose. Piot and his bleeding and battered fellow passengers were sandwiched between heavy crates of cargo, some of which carried thousands of samples of lethal Ebola-infected animal and human tissue and blood samples.
Convinced he was going to die, Piot found himself thinking not of his wife or his past life, but of the epidemic.
“Shit,†he muttered, “all that work for nothing. Nobody will ever know the answers.â€
Piot’s fellow travelers became nauseated; some had suffered contusions and broken bones. For the rest of their relatively uneventful two-hour flight to Kinshasa the only sound heard above the engines’ roar was the sobbing of terrified and injured passengers.
When Peter Piot staggered off the last of a series of planes into the Christmas chill of Antwerp, he found Margarethe obviously pregnant. And suddenly the full weight of what he had been through since September, of his many brushes with death—some foolhardy—hit him like a bolt.
Still, he had tasted adventure, and Piot would never again be satisfied for long with the seemingly mundane life of laboratory science.
Both van der Gröen and Piot were deeply affected by their Zaire adventures, so much so that Guido, whose emotional fuse was normally so long that few had ever witnessed an outburst from the Belgian virologist, discovered rage. Dragging Piot along with him shortly after Christmas, van der Gröen marched into the headquarters of the Sisters of the Holy Heart of Maria.
“Our objective here is education,†the seething van der Gröen told Piot as they entered the office of the order’s Mother Superior.
The meeting began calmly enough, with the two scientists applauding the Catholic education of children in the Yambuku area—an assignation that dated back to 1935. The men also noted the well-intentioned origins of the order’s medical effort, which stemmed from its relatively recent recognition that some 50 percent of the schoolchildren were chronically absent from classes in Yambuku due to illness. The order sought to improve school attendance by maintaining child health.
The Coming Plague Page 23