The Coming Plague

by Laurie Garrett

  In 1901 American Army physician Walter Reed and Cuban doctor Carlos Finley figured out the link between the A. aegypti mosquito, the virus, and the importance of uncovered pools of clear water, and started a hemisphere-wide effort to eradicate the mosquito. The mosquito, they discovered, could only leave its eggs in clear, clean water, so it thrived around people, lived in human homes, and left its larvae in jugs of drinking water. The insect was also constrained by temperatures below 60°F and only thrived in humid climates over 72°F. It seemed immediately obvious, then, that the entire yellow fever problem could be greatly reduced by simply covering all clean water supplies during warm months.

  In 1927 a vaccine was developed and the first official global disease eradication effort began, endorsed by the governments of the America.25

  The language of yellow fever efforts shifted from “eradication” to “control” and “conquest” following Fred Soper’s 1932 discovery that some monkeys harmlessly harbored the virus.26 In subsequent years, scientists discovered that several species of monkeys and apes could carry the virus, both in Africa and in South America. In the Americas, capuchin monkeys were unharmed by the virus, but carried yellow fever and could be a source of the microbe for feeding mosquitoes. In contrast, when yellow fever hit Central America, epidemics virtually exterminated the nonimmune Ateles and Alouatta monkey populations.27

  In short order it was also discovered that A. aegypti wasn’t the only mosquito that could carry yellow fever: A. africans, A. simpsoni, and A. albopictus, to name a few, could carry the virus. Furthermore, the virus could be passed from one mosquito generation to the next in the insect’s eggs; this allowed for long periods of time—several insect generations—when the disease seemed to disappear. But the virus was actually silently residing in generations of monkeys and mosquitoes, ready to reappear in human epidemic form under the proper conditions.28

  The harsh significance of this jungle/monkey form of yellow fever hit home in 1949 when the disease broke out again in Panama, reversing more than forty years of successful eradication begun in the days of Walter Reed. From there it spread northward through Costa Rica, Guatemala, and Mexico, forcing U.S. military and PAHO intervention for control. By 1959 cases of yellow fever were cropping up in areas all over South America where authorities thought eradication had been successful. In most outbreaks, the first cases involved men who worked in agriculture or timbering on the edges of tropical rain forests; there, they came in contact with wild mosquitoes that fed on monkey carriers.29

  By the late 1950s scientists realized that there were two types of yellow fever: the urban form associated with A. aegypti and the forest or sylvan form that could be found in a variety of monkeys and wild mosquitoes. Eradication of the urban form might be possible through vaccination, covering all water sources, and DDT spraying of insect breeding sites. But jungle yellow fever could not be eliminated without vaccinating all wild monkeys in Africa and South America, a clearly impossible task. Despite these hurdles of nature, WHO and PAHO remained optimistic about eliminating all human yellow fever disease because the vaccine protected people against both forms: if all children living in endemic areas were routinely vaccinated, they reasoned, the disease would only remain a threat to non-immunized foreigners traveling through jungle areas. Mass vaccination campaigns of the 1940s and 1950s drastically reduced human disease in both South America and West Africa.

  In the Americas, PAHO officials decided that the disease could further be prevented by eliminating the A. aegypti mosquito from the hemisphere, and from 1947 to 1960, the organization conducted a second massive campaign of mosquito control. In some countries, such as Argentina, Chile, Panama, Venezuela, and Colombia, DDT spraying and systematic covering of water sources radically reduced A. aegypti and public health officials were confident the insect could be wiped out of the Americas by the mid-1960s. But the U.S. Congress was never convinced such an effort was important for residents of the Northern Hemisphere, and, despite having formally committed itself to the PAHO campaign, never allocated funds for such an effort inside U.S. territory.

  Yet Congress, recognizing the diplomatic importance of appearing to comply with a PAHO edict for which the United States had voted, did order the CDC to attempt eradication. The effort was doomed from the start by hundreds of protesting property owners who threatened to sue if chemicals were sprayed in their yards or homes.

  In 1964, Dr. Donald Schleissman, who led the largely unfunded U.S. A. aegypti elimination effort, said of U. S. congressional commitment, “The mandate to eradicate aegypti with the funds available was equivalent to instructions to fly across the Atlantic with half a tank of gas.”

  Though its numbers were reduced temporarily, A. aegypti was never driven out of the Americas.

  Similar campaigns were carried out throughout equatorial Africa, but five yellow fever outbreaks occurred in the 1950s. A 1959 outbreak in Zaire only came to a halt when hundreds of thousands of people had been vaccinated and more than twenty tons of DDT were sprayed over a relatively confined area.30 In 1960 an enormous yellow fever epidemic broke out in western Ethiopia. By the time the epidemic died down in 1962, over 100,000 people had suffered the disease; yellow fever killed one out of three infected Ethiopians.

  A subtle change followed the Ethiopian epidemic. Without really discussing the matter, international experts slowly switched their tactics from the bold eradication ventures aimed at wiping out the disease to fire fighting. Research outposts were set up in yellow fever hot spots worldwide by the Rockefeller Foundation and a variety of government-associated agencies.31

  It was in such an outpost that Tom Monath, a CDC entomologist, worked at the University of Ibadan in Nigeria. Before he would leave Nigeria in 1972, Monath would travel all over the country trying to figure out where the virus hid between human epidemics. He would discover that a mosquito called Masoni africana could carry the virus throughout its habitat: the higher treetop levels of the Nupeko tropical forest lining the banks of Nigeria’s rivers.32

  Monath’s commitment to conquering yellow fever was solidified in late 1970, when he was part of a U.S.-Nigerian team that investigated an epidemic in Nigeria’s savanna plains of the Okwoga District. Over the Christmas holidays, Monath and his Nigerian colleagues made house-to-house surveys of Okwoga villages and medical clinics, searching for yellow fever cases and assisting Nigerian efforts to control the epidemic.

  “Has anybody here been sick lately?” Monath, a white Bostonian sporting a crew cut and smile, would ask when he arrived in a village. Time after time the scenario repeated itself: a villager would nod somberly and lead Monath into a thatched hut. There, a dead man would be sitting up straight in a chair, his eyes staring ahead, cotton plugs stuffed up his nostrils.

  The first time Monath beheld such a sight it scared the hell out of him, but after a while it was not the individual cases that troubled him, but the overall level of destruction inflicted by both the disease and the treatments used in some areas to allegedly cure yellow fever.

  He was also impressed by the fact that no original source for the 1970 epidemic could be found. Monkeys were scarce, there were no rain forests, yet in some villages one-third to half the residents showed blood-test evidence of recent infection. The overall infection rate in Okwoga was 14 percent, yet the most common yellow fever carrier, the A. aegypti mosquito, was virtually nonexistent in the area.33

  Monath and his colleagues were forced to conclude:

  The origin of the epidemic is not known. Two possibilities exist: (1) the Okwoga outbreak … resulted from the introduction of Yellow Fever Virus from a distant source at a time favourable for interhuman transmission in an immunologically susceptible population or (2) Yellow Fever is endemic … in or near Okwoga District.34

  In other words, either the disease was brought into the area by a traveler or it was there all along, hiding somehow for decades. There was an enormo
us biological gap between those two possibilities. Monath realized that not knowing which explanation was correct meant there was no way to determine how best to prevent future outbreaks in the area. Or any area.

  Hopes for controlling the insects that acted as vectors for yellow fever dimmed further still, as everywhere scientists looked another insect vector for yellow fever turned up. Karl Johnson found other virus-carrier species in Panama, Brazilian physician-scientist Francisco Pinheiro identified still more insect vectors in his country’s jungle interior, and U.S. Army researchers discovered that horse mosquitoes in Brazil and common ticks in West Africa could spread the virus.

  In 1972, convinced that it was fruitless to try to eliminate yellow fever, the Rockefeller Foundation shut down Monath’s lab in Ibadan and the other field stations. Years later Monath would still refer to the decision with bitterness. “A great opportunity has been blown,” he told colleagues, noting that between 1947 and 1972, A. aegypti had been eliminated from three-quarters of its pre-World War II habitat worldwide. Nineteen countries had eliminated the yellow-fever-carrying insect entirely by 1972, prompting the Washington consulting firm of Arthur D. Little to do a cost-benefit analysis of mounting a full-scale campaign to rid the Americas of the insect. The Little study determined that such an effort would clearly be desirable, even though the virus had a sylvatic cycle that allowed it to hide for long periods of time in wild monkeys and several other insect species. It reasoned that spending $326 million in the early 1970s to wipe out A. aegypti would bring human incidence of the disease down to near-zero levels in most Latin countries, because only that mosquito was infecting urban residents. Furthermore, A. aegypti was a far more efficient virus spreader; every major yellow fever epidemic of the nineteenth and twentieth centuries was spread by that mosquito. So, the consulting firm reasoned, a global campaign to eradicate A. aegypti could limit the yellow fever problem to levels entirely controllable through routine vaccination of people living or working in jungle areas.

  But the CDC disagreed; director David Sencer commissioned a rival study that concluded that A. aegypti eradication within the United States and Puerto Rico and the Virgin Islands alone would cost more than $200 million and speculated that an Americas-wide eradication would exceed $1 billion.35 The inflated cost was primarily due to private citizens’ refusal to allow spraying on their properties and widespread threats of lawsuits. Though poorer nations to the south spent enormous sums, successfully eliminating A. aegypti from much of the Americas, the wealthiest country in the hemisphere refused to get rid of its own mosquitoes.

  The effort died.

  Frustrated and disappointed, Monath packed his Ibadan laboratory into crates and bade his Nigerian colleagues farewell. But he wouldn’t be leaving Africa, not just yet. Something even deadlier than yellow fever awaited him.

  4

  Into the Woods

  LASSA FEVER

  I’m not afraid where we have to bring a risky, hazardous virus into the lab. I just hope and pray, and I don’t think about it.

  —Dr. Akinyele Fabiyi. Lagos. 1993

  Uwe Brinkmann’s head suddenly jerked up, he looked out the car window desperately searching for a familiar landmark along the back roads of northern Germany, and panic fell over him, the true deep panic that comes only when something taps into one’s innermost fears.

  “Now they’ve got me,” Brinkmann cried out in his mind. “Now I’m going to be gassed. They’re taking me to the concentration camp.”

  The sides of the van seemed to be closing in and Brinkmann had no idea where he was being taken. As he looked out the window in the summer of 1974, the city and suburbs of Hamburg gave way to countryside and then, he noted with fear, the woods.

  Sealed off from the anonymous driver and the entire outside world, Brinkmann and his companions stared ahead in shared terror. Brinkmann’s patient, German surgeon Bernhard Mandrella, lay in subdued delirium on a stretcher between them. To his side sat British physician Adam Cargill, who had treated Mandrella in Nigeria. With the men were three Nigerian women; a nurse/nun and two nurse assistants.

  “Nobody wanted us here to begin with,” physician-scientist Brinkmann thought. “So now they are going to get rid of us. All of us.”

  As claustrophobia overwhelmed him in their tightly sealed mobile unit, Brinkmann later said he was thinking, “How odd. I have spent the last seven days exposed to a lethal microbe, feeling no fear. Now it is people —my people—that terrify me.”

  But Brinkmann had never felt completely at home among his fellow Germans. His part-English family had carefully hidden the Jewish identity of Brinkmann’s grandmother throughout the years of the Third Reich, and young Uwe had made a career during the counterculture days of the 1960s out of crafty troublemaking. Similarly, his patient was the son of one of the military officers who tried to assassinate Adolf Hitler on July 20, 1944. Mandrella’s father was executed, and his mother was billed by the Third Reich for the cost of the hanging.

  “But this time it’s really too much, even for me,” Brinkmann thought. Taking stock, he could visualize how this group looked to German officials: three African women whose own government had sent them into isolation, an English physician who was suffering a suspicious case of diarrhea, a man apparently dying of a lethal contagious disease, and himself—a hippie troublemaker. He considered his black shoulder-length hair, thick unkempt mustache, tie-dyed T-shirt, and bell-bottoms. And he recalled headlines in German publications just weeks ago that denounced his famine-relief efforts in Ethiopia; Brinkmann was, the German press declared, creating communist communes in the deserts of the Horn of Africa. Though Ethiopian Emperor Haile Selassie had awarded Brinkmann his nation’s highest commendations and requested that the young hippie doctor remain indefinitely in the country, the German government recalled Uwe. It seemed that Brinkmann’s solution to Ethiopia’s ongoing food crisis—establishing village-based communal farms and produce-marketing apparatuses—was a little too left-wing for the conservative West Germans.

  “Yes,” he thought in those seconds of panic, “it makes sense. They will simply eliminate us and tell the world we died of the disease. That will take care of everything.”

  There was little to comfort Brinkmann when the caravan reached its destination. Just outside the village of Ebstorf, in the woods some fifty miles south of Hamburg, was an abandoned medieval monastery, recently converted to a high-security facility for smallpox containment. A series of three automatic air-lock doors opened for the anxious group, quickly shutting behind to seal them off from the rest of humanity.

  Inside were several sleeping rooms, an autopsy laboratory, and research facilities. Sophisticated research devices rested atop aseptic surfaces.

  Though there was an autopsy facility, there was no place for patient treatment.

  The group settled in as best they could, but tensions were thigh. The Nigerian women had never set foot outside of the Jos region in which they were born before Mandrella came down with the dreaded disease. Then, having tended to the physician in their Jos hospital, the nurses accompanied the patient to the University of Ibadan Hospital, one of Nigeria’s premier medical facilities.

  Mandrella’s problems began two weeks earlier when his colleague, Dr. Egon Sauerwald, was treating a patient from the old colonial city of Enugu in their St. Charles Mission Hospital, miles away in Borromeo. The patient had high fevers, chills, muscle aches, and a sore throat. Despite Sauerwald’s efforts, the Enugu man died. Days later, the twenty-nine-year-old doctor developed the same symptoms, quickly descending into acute disease.

  Mandrella did everything possible to save his colleague from the mysterious ailment, but Sauerwald continued to deteriorate. He sent Sauerwald’s blood samples to Ibadan, from where they made their way to CDC laboratories in Atlanta.
Word eventually got back that Sauerwald was infected with the recently discovered Lassa virus, a microbe that the U.S. Centers for Disease Control said was “thought to have a unique proclivity for killing doctors and nurses.”12

  The news was too late for Mandrella. By the time word got back that Sauerwald was infected with an exotic lethal virus, the thirty-three-year-old Mandrella had already performed a last-ditch bloody procedure to save his friend. The virus had so devastated Sauerwald’s throat that the doctor couldn’t breathe, so Mandrella made an incision into his friend’s trachea, creating an air hole in his neck. Mandrella was unprepared for the sudden gust of mucus that flew from his friend’s throat. He was instantly spattered with Sauerwald’s blood. Though he pulled away quickly, Mandrella’s face had been very close to Sauerwald’s neck as he made the incision, and the surgeon inhaled microscopic bits of blood and mucus.

  Mandrella was infected, and in a couple of days he too was shivering with Lassa fever. Still unaware of the CDC laboratory findings, Mandrella saw Dr. Hal White, an American physician who ran the missionary hospital in Jos. White examined Mandrella and warned the young doctor that the symptoms looked suspiciously like those of Lassa fever. As a precaution, White injected Mandrella with a unit of sera donated years earlier by nurse Lily (“Penny”) Pinneo. At White’s advice, Mandrella immediately drove to the metropolis of Ibadan, where he came under the care of British physician Adam Cargill of the University Hospital.