One was a distinguished Army surgeon, destined to go down in history as the man who solved one of medicine's most baffling and vexing mysteries. The other, a lesser-known clinician who'd studied in Baltimore, was a fearless medical adventurer who placed his own life on the line in the search for a cure.
Together, just more than a century ago, Walter Reed and James Carroll helped rid the world of the yellow fever menace - but not before surviving a personal relationship that veered from mutual respect to jealousy and distrust before their time together was through.
That's the lively picture that emerges from a rare collection of letters acquired last month by the Health Sciences and Human Services Library at the University of Maryland, Baltimore, letters medical historians have long sought for the insight they offer into the thinking of two visionaries on the brink of a world-altering discovery.
"This is a major gift, the most significant in my 20 years here," says Richard Behles, the preservation officer in the special collections department at the library on Lombard Street. "The Reed findings are as important to medical history as [William] Jenner's discovery of vaccination, but the letters show that these men were interesting, complicated personalities. It's the kind of material librarians kill for."
Emeritus professor of medicine Theodore Woodward made the bequest Dec. 6. A medical historian, he acquired the letters years ago from distant relatives of Carroll. To Behles and M.J. Tooey, the library's executive director, the bequest was an unexpected blessing.
"We knew of the existence of these letters," says Behles, "but it wasn't clear they'd ever be found. Dr. Woodward is 90 now, and slowing down; he doesn't come to campus as often as he used to. A colleague was cleaning out his office and found them."
The gift is so new that the library hasn't settled on plans for its conservation or display. For now, the letters are encased in plastic, piled neatly in a box in the library's wood-paneled reading room.
But Behles and Tooey are happy to offer glimpses of the letters, of a pivotal era in medical history, and of the interaction between Reed and Carroll, two strikingly different turn-of-the-century scientists in search of a common goal.
Yellow fever, Behles says, had plagued America since Colonial days. Periodic outbreaks, mostly in southeastern and Mid-Atlantic port cities, had claimed hundreds and sometimes thousands of lives at a time, including epidemics in Baltimore in 1794 and 1797 that killed more than 900 combined. A 1793 outbreak in Philadelphia, then the nation's capital, claimed more than 4,500 lives, fully 10 percent of the city's population, and terrified the nation.
Yet no one knew what caused yellow fever or caused it to spread.
At the time, America's most widely known physician, Benjamin Rush of Philadelphia, was considered the authority on the disease. "He thought it was directly contagious, conveyed through a sort of miasma, or vapor, in the air," says Behles. "This was a man who had signed the Declaration of Independence. If Benjamin Rush had a theory, you didn't question it." His prescription even called for bloodletting.
In time, Tooey says, a succession of Baltimore-based physicians, among others, challenged the "contagion" hypothesis with increasing vigor.
In 1900, the U.S. Army surgeon general chose one such man, James Carroll - an 1891 graduate of University of Maryland, Baltimore's medical school who later studied at Johns Hopkins - to serve on the U.S. Army Yellow Fever Commission that was sent to Cuba, a land blighted with the disease. Carroll became second-in-command to the panel's chairman, the widely known Army surgeon, Walter Reed.
The two men set forth to test a newer hypothesis: that mosquitoes, not person-to-person contact, spread yellow fever. The pairing of Reed and Carroll began what would become a fruitful but problematic friendship.
Fight for credit
The letters do nothing to undercut Reed's reputation as a world-class researcher, but he does come across as the more cautious of the two, a scientist nearly as fixated on his panel's place in history, and his own, as on the experiments themselves.
"The finding of certain intracellular bodies in Borax-Methylene blue is ... interesting," he writes in 1901. "I can hardly believe these are the long-sought parasite, although I sincerely hope so. How delightful it would be if the disease could be diagnosed microscopically!"
Reed later returned to Washington, from which safe remove he supervised the remainder of the mission. In one letter, he cast a jaundiced eye on perceived competitors. "Have you heard that the Marine Hospital Service has started what they call 'A Yellow Fever Institute?'" he asks sarcastically. "[They say] the time has arrived when yellow fever should be studied! A little late, don't you think? What honking asses!"
For his part, Carroll remained in Cuba until the end of the mission, where he oversaw day-to-day operations. In the story's most amazing turn, he decided it was necessary to use human subjects in the experiments. He volunteered personally. In August 1900, he allowed himself to be bitten by a mosquito that had feasted on yellow-fever patients, and he became violently ill.
The mosquito in question, an urban strain called Aedes aegypti, did indeed appear to be the culprit, and Carroll hovered near death for several days.
After recovering, he wrote a letter that showed he wasn't above questioning the courage of his superior. "My friend will now be brave as a lion now that the y.f. season is over," he writes his wife, Jennie, that October. "He will take particular care not to take the same chance I did."
It's human nature, Behles says, for researchers to squabble over credit in any high-profile science project, and a later missive shows Carroll was unexceptional in this way.
"I will never get [recognition]," he writes, "as long as it is in my friend's power to present [our findings]. ... I send you today's Havana paper, in which I have marked an editorial referring to our work in which great credit is given to Drs. Reed and Agramento [a commission member], and I am not mentioned."
Reed shows the compassion for which he's famous, frequently complimenting Carroll on his thoroughness, and he waxes empathic when commission member Jesse Lazear, a 34-year-old surgeon from Baltimore, dies of the fever. At other times, though, he too reverts to something like paranoia.
"Ten to one Santiago [another colleague in Cuba] will now claim the theory and the proof," he writes in August 1901, long after the commission had fingered Aedes aegypti.
The commission's work had immediate and lasting effects. The chief sanitary officer for Cuba, Col. William Gorgas, quickly eradicated breeding places for mosquitoes in Havana, which wiped out yellow fever in that city by 1902. Later, he applied the same techniques in Panama, permitting the United States to complete the Panama Canal in 1914. And the new attention public health officials lavished on anti-mosquito measures, such as the draining of swamps, all but eliminated yellow fever in the United States. Few living physicians in America have ever seen a case.
Reed died of appendicitis complications in 1902, at age 51; colleagues saw his exposure to yellow fever during his work on the commission as a factor. Carroll never felt well after his violent illness and died, also at 51, in 1907. Reed, for whom the Walter Reed Army Medical Center in Washington is named, got most of the credit for their accomplishment; Carroll had to settle for knowing that some insiders saw him as the unsung hero.
In the end, the cache of letters - which Behles plans to scan and put on the University of Maryland's Web site - does less to advance scientific knowledge than to offer a fuller context for understanding the scientists involved.
"There's a lot of scholarly literature on the Reed Commission's findings," says Ray Kondratas, head medical curator for the Smithsonian's National Museum of Natural History, "but very little of it tells of the intrigue, the personalities that went into the work. That interests historians today."
If so, they ought to have fun with what Behles calls the "Eureka we've found it!" letter, in which Reed proclaims the panel's historic discovery. On Sept. 7, 1900, he scrawled on one missive the words: "Did the mosquito do it?"
He then answers his own question.
"Hip! Hip! Hurrah!" Reed writes to Carroll, his underling and competitor, and now to posterity. "God be praised for the news from Cuba today! ... I shall simply go out and get boiling drunk."