world rather cleaner than American cities of the period. Of Havana during the summer of 1900, Gorgas wrote, in his book "Sanitation in Panama": "I believe that Havana was cleaner than any other city had ever been up to that time." How this transformation of an alien city was brought about by American army officers without rasping the sensibilities of the natives to the point of resistance is a story in itself. That it was done, and with a minimum of ill-feeling on the part of the Cubans, is a testimonial to the extraordinary executive capacity, combined with the tact and considerateness, of the American officers.

By courtesy of U. S. Signal Corps.

George M. Sternberg, surgeon-general at the head of the Army Medical Service at the time when physicians in the service discovered the cause of yellow fever and the means of its prevention.

The cleanliness of Havana following the occupation of the city by the American military authorities constituted the greatest of the reasons for the satisfaction of Gorgas and his fellow officers. They saw filth had gone; they felt sure that with filth, yellow fever also would depart.

Statistics seemed to justify their faith. During the first seven months of 1899 only seven deaths occurred from yellow fever.

V

But beginning in August of that year, 1899, immigrants from Spain began to come into Cuba. Between August and December, 1899, some 12,000 Spanish peasants ar

YELLOW FEVER NOT CONQUERED

44I

rived in Havana. With their presence yellow fever began to appear again. Whereas there had been but one death from this cause in January, 1899, there were eight in January, 1900. Throughout 1900 the epidemic grew. In all, fourteen hundred

cases were reported, constituting, as it was put, with some exaggeration, by General Fitzhugh Lee, consul-general of the United States in Cuba, and a resident of many years in Havana, the worst outbreak the country had ever known.

It was clear that yellow fever had not been conquered, or even scotched. The presence of the new immigrants was the test. Necessarily they were nonimmune, that is, they had not achieved immunity through having had the disease. The resident population of Havana was largely immune. It was to this fact, and not to the work of Major Gorgas and his associates, that the apparent success of 1899 had been due. It was now clear that sanitation, and such cleanliness as few cities anywhere had ever known, had not conquered yellow fever, nor affected it at all. The disease had not been destroyed, it had merely been quiescent for lack of material on which to feed. The satisfaction and confident hope which had been the mood of the American army physicians and sanitary

Major-General Leonard Wood was Governor-General of Cuba, 1900. General Wood's presence as Governor-General of Cuba had historic importance in the fact that being a medical man he understood Colonel Gorgas's epoch-making effort to stamp out yellow fever, and gave him indispensable support.

officers in 1899, became, by the spring of 1900, baffled dismay.

From all sides hysteria clamored at the American officials. Nobody knew what should be done, but everybody demanded that something be done quickly. The pressure made itself felt in Washington; in June, 1900, SurgeonGeneral George M. Sternberg appointed a commission of four army surgeons Walter Reed, James Carroll,

Jesse W. Lazear, and Aristides Agramonte
Havana and investigate.

VI

to go to

While Gorgas and his superior, Governor-General Leonard Wood, had been cleaning up Havana and preoccupied with the problem of yellow fever, they had come into frequent contact with an amiable old Cuban physician, Doctor Carlos J. Finlay. From the start Finlay used to throw friendly doubt on the theory that yellow fever was caused by filth. He was sceptical of Gorgas's expectation that the disease would vanish when the city was cleaned. Finlay had a theory, which he had clung to tenaciously for twenty years, that yellow fever was caused by the bite of a mosquito of the variety called Stegomyia. Being a man of cultivated mind and magnetic personality, Finlay, while expounding his theory, was always listened to politely; but as happens with many true prophets, few were converted to his belief. Mosquitoes of about 800 different species were known; how could it be possible that of these 800 Finlay had been able to fix on the one particular variety as the culprit? The idea bordered on the fantastic! Nor could Finlay bring forward evidence convincing to the scientific mind. On the contrary, the results of his own experiments with mosquitoes was destructive to the very theory he wanted