Anderson employs the first person point of view. The fourteen-year-old protagonist, Mattie, gives readers the facts of Philadelphia and the epidemic quickly.

Anderson selected the title Fever 1793 because the story occurs during the period when Philadelphia suffered severe losses from the 1793 yellow fever epidemic. Set in the post-Revolutionary era, the story explores the worldwide themes of friendship and death. As Mattie matures, she learns perseverance, hope, and self-reliance.

Mattie is in conflict with her mother, at odds with her body, and is dreaming about her future when she hears about the death of her childhood friend Polly. Shocked, she finds little time to grieve as she helps her mother serve coffeehouse clients. Confused about what killed Polly, Mattie and her family begin to hear about yellow fever but quickly dismiss the predictions as pessimistic.

Readers learn in the first chapter about Mattie's crush on Nathaniel Benson. Nathaniel enjoys Mattie's sharp wit and her zest to try new things. Together they reminisce about the launch of Blanchard's hot air balloon, an event symbolic of the new attitudes that Mattie and Nathaniel embrace. Nathaniel gives Mattie flowers as a way to remember him as the city locks its doors to the fever. Mattie's memories help her to endure her many hardships. It is this hope that keeps Mattie going until the first frost that ends the epidemic.

Lucinda, Mattie's mother, serves as the antagonist. Widowed for several years, she raises Mattie by herself as she manages the coffeehouse. Lucinda knows how to persevere through tough times, and she passes on this ability to Mattie.

Mattie describes her mother as the type of person who "had given birth . . . in the morning and cooked supper for ten that night." Lucinda drives herself hard. Luanda's callous character forces Mattie to stand up for herself. Mattie wonders if her mother enjoys her life or if it is filled with bitterness. She shows little compassion for herself or for Mattie, making Mattie's journey to adulthood a hard one.

Lucinda gets yellow fever. Mattie finds out when a stranger dumps her out of a wheelbarrow in front of the coffeehouse. For the first time, Mattie sees her mother out of control. Mattie fears for her mother's life as she sees her mother shiver and vomit uncontrollably. Luanda's eyes are poisoned with streaks of yellow and red. Mattie, like her mother, puts her fears and sadness aside so that she can go about...