Yellow fever seems to play a role in single, sudden breakouts of the disease. Three epidemiologically different infectious cycles occur, in which the virus is transmitted from mosquitoes to humans or other primates. In the "urban cycle", only the yellow fever mosquito "A. aegypti" is involved. It is well adapted to urban areas, and can also transmit other diseases, including Zika fever, dengue fever, and chikungunya. The urban cycle is responsible for the major outbreaks of yellow fever that occur in Africa. Except for an outbreak in Bolivia in 1999, this urban cycle no longer exists in South America. Besides the urban
Yellow Fever Commission Yellow Fever Commission The Yellow Fever Commission was a research team of the United States Army which researched treatment for yellow fever. The research process itself became a focus of study for later generations. A United States nurse named Clara Maass and two Spanish immigrants were among those who died as a result of their research participation. Researchers mark the research of the Yellow Fever Commission as the origin of the model of modern consent in medical research. The 1934 play "Yellow Jack" told the story of Walter Reed in the Yellow Fever Commission. That play was the basis of