Yellow Fever (fiebre amarilla; vómito negro)

A mosquito-borne disease with high mortality whose urban form probably crossed the Atlantic through the African slave trade, yellow fever was known in Havana by 1720, possibly by l647. The native Cuban population soon acquired a degree of immunity and serious outbreaks were mostly associated with a big influx of immigrants or visitors. The 6,008 deaths among invading troops during the British occupation of 1762-1763 in an outbreak supposedly due to the arrival of an infected merchant ship from Veracruz the year before, was a factor in Britain’s eventual exchange of Cuba for Florida. From then on the fever was endemic, with a high point of 2,058 deaths in Havana in1857. The mortality rate was around 3% of those infected but reached almost 10% in 1898. Cuba was also the origin of shipborne outbreaks in the United States, notably in Philadelphia in 1793, which ended when winter killed off the insect vectors. During the first United States intervention, with 1,400 cases in the summer of 1900, despite great efforts of cleaning up Havana, the desperate authorities decided to act against mosquitoes in accordance with the theories of Carlos J. Finlay. By the end of 1901, Havana’s mosquito population had been reduced 90% and there had been no deaths for three months. The disease was, however, reintroduced, from New Orleans, in October 1905, and although soon extinguished in the capital, lingered on in small towns, producing a serious outbreak in Oriente province in 1908. The extension of the now standard preventive measures to rural Cuba finally eliminated the disease from the island within a few months. But it remained vulnerable to reinfection from foci in Mexico, Central American and northern South America. In March 1954 a nationwide campaign was begun to eradicate the aedes aegypti vector. By late 1958 this had gotten rid of the mosquito from 95% of its breeding places, but failed at total elimination, as the subsequent spread of dengue fever by the same insect amply showed.