History of yellow fever as a result of the numerous deaths, of the French company licensed to build the canal resulted in a massive financial crisis in France. History of yellow fever The evolutionary origins of yellow fever most likely lie in Africa. Phylogenetic analyses indicate that the virus originated from East or Central Africa, with transmission between primates and humans, and spread from there to West Africa. The virus as well as the vector "Aedes aegypti", a mosquito species, were probably brought to the western hemisphere and the Americas by slave trade ships from Africa after the first European exploration in 1492. The
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