I was reading a book last night about a parallel american history... In the book it talks about a yellow fever epidemic in New Orleans somewhere between 1810 and 1860. I was wondering, was there really such an epidemic, or was it a complete inovation by the author.

I believe I saw something on the History Channel about it. I'm going to go with yes, a real epidemic.

I did a bit of research and I found on a list of epidemics, that there was a yellow fever epidemic in 1847. I'm trying now to find more information on that epidemic, like did it have any effect on political history etc. that happened.

Yellow Fever Deaths in New Orleans, 1817-1905

More than 41,000 people died from the scourge of yellow fever in New Orleans between the years 1817 (the first year that reliable statistics are available; surely there were deaths in earlier times) and 1905 (the Crescent City's last epidemic). The number of fatalities ranged from none in years that the plague spared New Orleans to more than a thousand in nine of the eighty-eight years of the fever's activity.
Louisiana Division New Orleans Public Library