The Secret of the Yellow Death

by Suzanne Jurmain

  And that was a problem. As far as the team knew, animals didn’t get yellow fever. That meant the infected mosquitoes would have to bite a group of people.

  But who? Who was going to be bitten?

  The decision would have to be made soon. Reed had to return to the United States August 2, and it was important to get the new mosquito research started.

  On the night of August 1—when, for some unknown reason, Agramonte was not present—Reed, Carroll, and Lazear met at Camp Columbia. They discussed the problem and decided that all three of them would volunteer for the experiments.

  Of course, if Carlos Finlay and Jesse Lazear were right—if mosquitoes did carry the disease germs—a human volunteer bitten by an infected bug could get yellow fever and die of the disease. That was the risk. But all three doctors were prepared to face it. To fight the illness they were ready to take what Dr. Carroll later called “a soldier’s chances.”

  August 1–30, 1900

  It sounded so simple. All Lazear had to do was put the mosquito eggs in water, keep the water in a warm place, and wait a couple of weeks until the eggs hatched and grew into mature insects.

  But it wasn’t that easy. Some eggs just floated on the water and didn’t hatch. Some insects died before they were completely grown up. Others dropped dead almost as soon as they became adults. Still, Lazear didn’t give up. He tended his mosquitoes as if they were babies. Each day, he checked the progress of his little group. He made sure the adult insects were fed sweetened water and bits of banana. Sometimes he even let the females bite him and his lab attendants to make sure that they had nourishing drinks of blood. At last, when the insects were fully grown, Dr. Lazear put each mature female in a test tube. He plugged the opening with a fluffy cotton stopper and carried his tubes of mosquitoes to the yellow fever wards at Las Animas Hospital in Havana.

  Two unknown people standing outside Las Animas Hospital in Havana, Cuba. Since many yellow fever patients were taken to Las Animas, members of the Reed team often did autopsies and experiments there.

  On the hot August days, Lazear walked through the wards, stopping occasionally at a yellow fever patient’s bedside to let one of his female mosquitoes bite.

  It was a delicate process. First he turned the tube upside down so that the mosquito would fly upward into the glass end of the tube. Then Lazear swiftly removed the cotton plug and placed the open end of the tube flat on the patient’s arm or belly. Patiently, he watched as the mosquito settled, inserted its proboscis through the skin, and sucked. After that, Lazear waited until the insect flew toward the top of the container. Then he picked up the tube, replaced the stopper, and noted down the date, the name of the patient who had been bitten, the number of days the patient had been ill, and the severity of the case. After several days passed, he let each one of these “infected” mosquitoes bite himself or another healthy volunteer.

  But nothing happened. No one got sick.

  Was the mosquito theory wrong? Was it another dead end?

  The results were discouraging. Scientific progress, however, doesn’t usually happen overnight, and Jesse Lazear was trying to be patient. Day after day, he tended his bugs. He wrote up his notes, and—even when he wasn’t thinking about bugs—he must have worried. Far away, back in the States, his wife was lying in a hospital, suffering through complications of her second pregnancy. The baby was due any day, and Jesse Lazear was waiting for news.

  August 15 passed. Then August 20. Finally, on August 25 a telegram arrived. Dr. Lazear’s wife had successfully given birth to their second child, a baby girl. Of course, Lazear wouldn’t actually get to meet his new daughter until he went home for a few weeks of leave in October. But it was a wonderful thing to think about. And by the end of August, Jesse Lazear probably needed all the wonderful thoughts that he could get, because his insect experiments were going very badly.

  A female mosquito biting.

  For weeks Lazear had pinned his hopes on the mosquito theory. For weeks he’d waited for a breakthrough. But by August 25 Jesse Lazear had tried to use mosquitoes to produce yellow fever in healthy people on nine distinct occasions. All his experiments had failed. Many of his bugs had died. Almost every day there were new frustrations, and the events on August 27 were all too typical. On that day an insect, one that had bitten a yellow fever patient on the second day of his sickness twelve days earlier, refused to bite another volunteer at Las Animas Hospital. Worse still, the bug looked weak. Lazear figured it would probably spoil his experiment by dying before morning, but he brought it back to the laboratory at Camp Columbia anyway.

  Carroll was in the lab when Lazear came in, and the two men began to chat about the insect work. The truth was the mosquitoes seemed absolutely “harmless.” Keeping them alive had become a major nuisance—and, in passing, Lazear told Carroll how his sickly bug had behaved that very morning.

  Carroll had never believed in the mosquito theory, but he could easily see his colleague needed help. Since there was a chance that blood would help perk up the little insect, Carroll offered to let the feeble bug bite him.

  At two p.m. Lazear turned the test tube upside down on Carroll’s arm. He held it in place, and waited for the feeble mosquito to fly down and suck.

  But the bug refused to settle. It fluttered here and there, landing again and again on the smooth sides of the tube. Minutes passed. The two men waited. Then, finally, Carroll took the tube out of Lazear’s hand. He held it against his own arm and sat there patiently until, at last, the insect landed, bit, and drank its fill.

  That took care of that.

  Lazear put his test tubes full of bugs away, and Carroll went on with his lab work.

  Later that week, on August 30, James Carroll and Alva Pinto, another army doctor, went down to a nearby beach to take a swim. The water was warm, but suddenly Carroll felt a chill. Moments later he had a headache—a fierce headache that seemed to be burning a hole straight through his brain. The pain was terrible, and by the time Carroll pulled himself out of the ocean, he didn’t look well. Dr. Pinto glanced in his direction, saw the bacteriologist, and made an instant diagnosis. “Yellow fever,” he said succinctly

  “Don’t be a . . . fool,” Carroll responded. “I have no such thing.”

  Modern photo of a hundred-year-old microscope. Dr. Carroll probably used a microscope like this for research.

  August 31–September 4, 1900

  Of course, James Carroll had always known that Cuba was full of dangerous diseases. He’d known that coming to the island was a risk. And, yes, the bite from Lazear’s sickly little bug could possibly have given him the fever. But James Carroll had never believed in the mosquito theory. He’d never thought that insects carried the disease. Besides, he couldn’t afford to get the illness. He was a forty-six-year-old married man with five small children to support—and yellow fever often killed people over forty.

  Still, there was no getting around the fact that his temperature was rising. Something was making him sick. And he needed to know exactly what the illness was.

  It might be malaria. That could cause high fevers. It was a bad disease; but, still, it could be treated. It wasn’t usually as deadly as yellow fever. Besides, malaria was often found in Cuba. Carroll could have picked up the infection. And the scientist knew there was an easy way of finding out.

  Early in the morning on August 31, James Carroll dragged himself over to the lab. He jabbed himself with a needle and drew some blood. Then he smeared it on a glass slide and put the slide under the microscope. Carefully, he peered through the eyepiece, focused the lenses, and began to look.

  Modern photo of a drop of blood that has been placed on a glass slide for viewing under a microscope. The slide Dr. Carroll examined the morning he felt ill probably looked like this.

  For several minutes he scanned the slide. There were plenty of roundish red cells. There were a few irregularly shaped white cells. But no definite sign of malaria—or of yellow fever. The trouble was, that didn’t
prove a thing. Diagnosing illness with a microscope was often difficult. Sometimes yellow fever patients had fewer white cells in their blood. But often yellow fever blood looked pretty normal. And malaria? That was tricky, too. Sometimes it was hard to see the tiny organisms that caused the illness in a single drop of blood.

  Clearly, the microscope wasn’t going to provide a simple answer. And as James Carroll looked up from the eyepiece, he must have known that there was nothing else to do but wait.

  If it was malaria, he’d know it soon. There would be violent, periodic fevers, vomiting, sores around his lips, and soaking sweats. And if it was yellow fever, well, he’d recognize the bloodshot eyes, the bleeding nose and gums, and the awful yellow skin. One way or another, he’d find out about his illness soon enough.

  Nobody knows how long Carroll sat in front of his microscope that morning. But he was still there when Lazear and Agramonte walked through the laboratory door—and stared. Carroll looked awful. His face was flushed; his eyes were red. But he tried to joke. The illness was nothing, he said. He’d just somehow “caught cold.”

  Both doctors begged him to go to bed. Carroll, however, was a stubborn man. As a youngster he’d struggled against poverty. He’d fought to go to medical school. He was used to hardships, and he wasn’t the sort who’d let a little bout of sickness beat him down. Still, finally, he agreed to stretch out on a sofa.

  Microscopic view of the one-celled organism that causes malaria (the dark patch) among blood cells. This is what Dr. Carroll probably expected to see in his blood when he became sick.

  It didn’t help. By afternoon, James Carroll was lying in the hospital. At seven p.m. his temperature had reached 102. Soon there was no question about the diagnosis: the scientist had come down with yellow fever.

  But how could he have gotten the disease? In a state bordering on panic, Lazear and Agramonte reviewed the possibilities.

  Could it have happened when Carroll visited the autopsy room at Las Animas Hospital in Havana a few days earlier? Could that be where he’d picked up the infection?

  Or had it happened in the Camp Columbia lab when Carroll let Lazear’s enfeebled little insect bite his arm?

  Both doctors knew that there was only one good way to find an answer. They would have to let the mosquito that bit Carroll bite another person. Then they would have to see if that victim developed a clear-cut case of the disease.

  The experiment was basically simple. But to do it, they had to have a healthy volunteer.

  Agramonte wasn’t a good candidate. There was a chance he’d had a very mild case of yellow fever while growing up in Cuba and now might be completely immune to the disease.

  Lazear wasn’t a great choice either. He’d already been bitten several times by mosquitoes that had previously bitten yellow fever patients. Since those bites hadn’t made him sick, there was a chance he, too, might actually be immune to the disease.

  A fresh volunteer would be best.

  The scientists had barely come to that conclusion when Private William Dean walked by the lab and happened to look in.

  Dean, a young unmarried man, had just arrived in Cuba. He’d never been near Carroll or any other yellow fever victims, but he had certainly heard a lot about the team’s experiments.

  “You still fooling with mosquitoes, Doctor?” Dean asked, as he stood in the doorway.

  “Yes,” said Lazear. ‘Will you take a bite?”

  “Sure. I ain’t scared of ’em,” Dean replied.

  Lazear looked at Agramonte. Agramonte nodded. The young private seemed to be the perfect volunteer.

  Dr. Lazear picked up the tube containing the mosquito that had bitten Carroll. He inverted the tube, pulled out the cotton plug, and placed the opening flat against Dean’s bare arm. The bug flew down, and all three men waited while it settled on the soldier’s skin, inserted its proboscis, and sucked blood.

  For the next few days, Lazear and Agramonte didn’t tell anyone at Camp Columbia about Carroll’s mosquito bite or Dean’s. Instead, they tried to work. They worried about Carroll, and they wondered privately if young Dean was going to get sick.

  Carroll himself lay in the hospital, fighting the disease. Roger Ames, the army doctor with the most experience in treating yellow fever, monitored the patient and saw the scientist’s temperature rise to 104. He watched as Dr. Carroll’s skin and bloodshot eyes turned lemon yellow. The sick man’s pulse was slow. His condition was definitely critical, but there was very little Dr. Ames could do. Available drugs like quinine, castor oil, mercury compounds, and opium had no effect on yellow fever. To combat the disease, Ames ordered nurses to keep the patient quiet. He made sure that Dr. Carroll ate nothing while the fever soared but insisted that the scientist sip lemonade or water every hour.

  At one point Carroll felt a sharp pain in his chest that seemed to stop his heart. Sometimes he babbled feverishly. But experiments were often on his mind. Once, when he ordered his nurse, Ms. Warner, to give the lab mosquitoes a meal of ripe banana, she obligingly obeyed. But when Dr. Carroll said that a mosquito bite had caused his illness, Nurse Warner was seriously shocked. A mosquito causing yellow fever? Why, everybody knew that Finlay’s theory was a joke. The whole idea was crazy, and, before she went off duty, Ms. Warner had formed her own opinion of the sick man’s silly statement. “Patient delirious,” she noted briefly on the chart.

  September 5–8, 1900

  The situation was serious. Carroll was desperately ill. Lazear and Agramonte were waiting to see if Dean would come down with yellow fever. And Reed, far away in Washington, D.C., could only wait for bulletins and wonder. Was Carroll’s attack simply a tragic accident? Or was it an important clue—a clue that would finally crack the yellow fever mystery? Upset and distracted, Reed poured out his feelings in a letter to his old friend Major Jefferson Kean. “I cannot begin to describe my mental distress and depression over this most unfortunate turn of affairs,” Reed wrote. To Reed, Carroll’s illness was terrible. It was worrying. But, from a scientific point of view, it was also fascinating. And the team’s chief investigator desperately wanted to know how Carroll had gotten sick. “Can it be that [the mosquito] was the source of infection?” he asked Kean.

  Dr. Carroll’s fever chart. This record shows his temperature, pulse, and rate of breathing during his attack of yellow fever.

  Walter Reed and his teenage daughter, Blossom. While Carroll was ill, Reed was home in the United States with his family.

  As the days went by, Reed got reports from Camp Columbia. For the most part, the word was grim. Carroll was suffering from violent headaches. Light hurt his eyes. The attack was severe. The fever was high. For several days it seemed Carroll might die. Then suddenly on September 7, there was wonderful news. For the first time in a week the sick man’s temperature was normal. The outlook for recovery was good, and Reed immediately dashed off a note:

  My Dear Carroll:

  Hip Hip Hurrah . . .

  Really I can never recall such a sense of relief in all my life, as the news of your recovery gives me. . . .

  God bless you, my boy.

  Then on the back of the envelope Reed scribbled: “Did the Mosquito Do It?”

  It was the big question. And—though Reed didn’t know it when he wrote that note—Lazear and Agramonte already had a clue.

  On September 5, about a week after he had been bitten by the mosquito, Private Dean didn’t feel well.

  At first the soldier was just a little weary and lightheaded. Then his eyes became bloodshot. His face flushed red, and his temperature soared. Soon Private Dean was in the hospital. It seemed that the mosquito that had bitten Carroll had caused another case of yellow fever.

  In the hospital, Dean suffered through a mild case of the disease. Carroll slowly started to recover, and Jesse Lazear was excited. On September 8 he sat down and sent his wife the latest news. “I rather think I am on the track of the real germ,” he wrote, “but nothing must be said as yet, not . . . a hint. I have not
mentioned it to a soul.”

  Private William Dean’s fever chart. The graph shows that Dean’s temperature went down quickly and that his attack of yellow fever was not as severe as Carroll’s.

  September 9–26, 1900

  In September an epidemic of yellow fever broke out in Havana. The hospitals admitted two hundred and sixty-nine cases, and one out of every five patients died. It was more important than ever to find a solution to the yellow fever problem, but manpower was in short supply. Carroll was still so weak from his attack that he couldn’t stand or change position without help. Agramonte was getting ready to return to the United States for a brief vacation. Reed was still in Washington, putting the finishing touches on his report.

  In Cuba, however, Jesse Lazear was working hard. Day after day he tended the insects, carried out experiments, and jotted down his records in a big lab notebook and another smaller book he carried in the pocket of his shirt. At last the work seemed to be paying off. The results looked promising. Both Carroll and Dean had developed yellow fever after mosquito bites. The trouble was, Lazear couldn’t be absolutely certain that Carroll’s case hadn’t been an accident. He couldn’t be one hundred percent sure that Carroll hadn’t gotten yellow fever from another source. And there were other questions, too. Why, for instance, had Carroll and Dean become sick when other people bitten by “infected” mosquitoes had managed to stay healthy? Was there something different or special about the insects that had bitten those two men? To make a breakthrough, Lazear would have to be able to answer all those questions. He’d need to know exactly how and when a mosquito could transmit the yellow fever germ—and he’d need to prove it beyond the slightest doubt. There were lots of experiments he had to do. And Jesse Lazear was doing them when, on September 13, he was bitten by a mosquito.