Yellow fever In 1873, Shreveport, Louisiana lost 759 citizens in an 80-day period to a Yellow fever epidemic, with over 400 additional victims eventually succumbing. The total death toll from August through November was approximately 1,200, In 1878, about 20,000 people died in a widespread epidemic in the Mississippi River Valley. That year, Memphis had an unusually large amount of rain, which led to an increase in the mosquito population. The result was a huge epidemic of yellow fever. The steamship "John D. Porter" took people fleeing Memphis northward in hopes of escaping the disease, but passengers were not allowed to disembark
Yellow fever vaccine It should not be given to those with very poor immune function. Yellow fever vaccine came into use in 1938. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. The wholesale price in the developing world is between US$4.30 and US$21.30 per dose as of 2014. In the United States it costs between US$50 and US$100. The vaccine is made from weakened yellow fever virus. Some countries require a yellow fever vaccination certificate before entry from a country where the disease is common. People most at risk