August 1793. Fourteen-year-old Mattie Cook is ambitious, adventurous, and sick to death of listening to her mother. Mattie has plans of her own. She wants to turn the Cook Coffeehouse into the finest business in Philadelphia, the capital of the new United States.

But the waterfront is abuzz with reports of disease. "Fever" spreads from the docks and creeps toward Mattie's home, threatening everything she holds dear

As the cemeteries fill with fever victims, fear turns to panic, and thousands flee the city. Then tragedy strikes the coffeehouse, and Mattie is trapped in a living nightmare. Suddenly, her struggle to build a better life must give way to something even more important -- the fight to stay alive.

Are you referring to..
Fever 1793 by Laurie Halse Anderson?

If you are then, I've read it. Its pretty good, but its kinda depressing, at least it has a happy ending!