History of yellow fever 1,235 fatalities were recorded of an estimated 12,000 cases. Smaller outbreaks occurred in Saint-Nazaire in France, Swansea in Wales, and in other European port cities following the arrival of vessels carrying the mosquito vector. The first mention of the disease by the name "yellow fever" occurred in 1744. Many famous people, mostly during the 18th through the 20th centuries, contracted and then recovered from, or died of, yellow fever. The Yellow Fever Epidemic of 1793 struck during the summer in Philadelphia, Pennsylvania, where the highest fatalities in the United States were recorded. The disease probably was brought by refugees and
Yellow fever titer (compared to an earlier sample) can confirm yellow fever. Together with clinical symptoms, the detection of IgM or a four-fold increase in IgG titer is considered sufficient indication for yellow fever. Since these tests can cross-react with other flaviviruses, such as dengue virus, these indirect methods cannot conclusively prove yellow fever infection. Liver biopsy can verify inflammation and necrosis of hepatocytes and detect viral antigens. Because of the bleeding tendency of yellow fever patients, a biopsy is only advisable "post mortem" to confirm the cause of death. In a differential diagnosis, infections with yellow fever must be distinguished from