hemorrhagic fever

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Yellow Fever. Yellow fever, a virus‐based infectious disease transmitted by female mosquitoes that breed in stagnant water, was long endemic in the tropics and in temperate regions during warm seasons. Depending on the severity, its effects range from fever and headache to chills, nausea, hemorrhage, and death. Although scattered outbreaks occurred earlier, the first major yellow fever epidemics in America broke out during the 1790s. Following outbreaks in the Caribbean, the disease flared in Philadelphia in 1793, disrupting the new federal government and engendering the first major controversy over the etiology (cause) of epidemic disease in the United States. One side argued that the disease arose spontaneously from the filth coating the streets and docks; others claimed it was an imported pestilence. Arguments about public‐health policy flowed from these theories, with one side promoting sanitation, and the other, quarantine. All segments of the population were affected, although the affluent found some protection in flight and African Americans appeared to suffer less than others.

By the mid‐nineteenth century, yellow fever had become principally a disease of southern ports, especially New Orleans. The argument over transmission and prevention continued, but with a new twist. Southern physicians practicing in rural areas became increasingly convinced that yellow fever could be transported, since they were able to tie rare outbreaks in their areas to contacts with epidemic centers. Physicians voiced a compromise “seed‐soil” theory, which held that “seeds” of the disease had to be imported but only thrived in the sort of welcoming environment provided by poor sanitation. Hence, both quarantine and sanitation should help prevent yellow fever.

The century's worst yellow fever outbreak struck the South in 1878, taking an estimated 10,000 lives. Its severity, and impact on trade, led directly to the formation of the first federal public‐health agency, the National Board of Health. This foray into national health policy ended in the early 1880s, but the standard was taken up again in the late 1880s by the Marine Hospital Service. This federal organization, previously charged with providing hospital care for sailors, assumed responsibility for yellow fever prevention after 1888 and in the early twentieth century evolved into the U.S. Public Health Service (USPHS). Both state and federal authorities built disinfecting quarantine stations in the 1880s and 1890s to kill the suspected yellow fever “germ,” although its identity eluded investigators.

After the U.S. occupation of Cuba in the Spanish‐American War, Surgeon General George Sternberg sent Walter Reed there as the head of a commission to study yellow fever. He and his colleagues established that the disease was caused by a virus and that it was spread by mosquitoes. In 1905 the USPHS used this knowledge to terminate the last U.S. yellow fever epidemic when it broke out in New Orleans.
See also Medicine: From 1776 to the 1870s; Medicine: From the 1870s to 1945.

Bibliography

Margaret Humphreys , Yellow Fever and the South, 1992.

Margaret Humphreys

hemorrhagic fever , any of a group of viral diseases characterized by sudden onset, muscle and joint pain, fever, bleeding, and shock from loss of blood. Bleeding occurs in the form of leakage from capillaries in the internal organs and the skin and mucous membranes. The causative viruses may be transmitted to humans by insects, ticks, or rodents, but in the case of the African hemorrhagic fevers, Ebola and Marburg, the animal carrier is unknown. In addition to Ebola and Marburg, well-known hemorrhagic fevers include hantavirus , Lassa fever , yellow fever , and a severe form of dengue called dengue hemorrhagic fever (see dengue fever ; see also Ebola virus ).

Ebola and Marburg are closely related, newly emergent viruses that have in recent years caused epidemics in central Africa, with very high rates of mortality. Hantavirus occurs in many different parts of the world and is spread to humans from field rodents via microscopic bits of their excretions that get into the air and are inhaled. It was originally known as a disease of Asia and Europe that primarily attacked the kidneys, but a more deadly pulmonary form of hantavirus infection has more recently caused numerous fatalities in the United States, Chile, and other countries. Lassa fever, also spread to humans from rodent excretions, occurs primarily in W Africa. Closely related to the Lassa virus are the Junin and Machupo viruses, which have caused outbreaks of hemorrhagic fever in South America. Yellow fever, transmitted by the bite of a mosquito, still occurs in tropical areas despite largely successful control efforts. Dengue hemorrhagic fever, also spread by mosquitoes, has in recent years caused many fatalities among children in tropical countries.

There is usually no specific treatment to combat the viruses that cause hemorrhagic fevers. One exception is the drug ribavirin, which has been effective in treating Lassa fever and has also been used to treat a form of hantavirus infection and Crimean-Congo hemorrhagic fever. Treatment generally consists of such supportive measures as the replacement of lost blood, the maintainence of fluid balance, and the alleviation of symptoms. Survival depends largely upon the virulence of the virus strain and the quality of treatment.

Bibliography: See R. Reston, The Hot Zone (1994).