Thanks to our sources for making this book possible:

Works Cited

“Key Facts About Influenza (Flu) | CDC.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, www.cdc.gov/flu/about/keyfacts.htm.

“Learn About Flu.” American Lung Association, 

www.lung.org/lung-health-and-diseases/lung-disease-lookup/influenza/learn-about-influ

Enza.html.

“The Flu Season | CDC.” Centers for Disease Control and Prevention, Centers for Disease

Control and Prevention, www.cdc.gov/flu/about/season/flu-season.htm.