The goal of Plague Inc is to wipe out all of mankind with a deadly disease. Apparently, the game's unique premise caught the attention of the Centers for Disease Control and Prevention (CDC). According to creator James Vaughan, the CDC reached out to him, as "it was something they were all playing."
Although Vaughan doesn't have a medical background, he says that he "tried to make it as scientifically plausible as possible." However, the CDC isn't necessarily interested in Vaughan's understanding of infectious disease. He told Polygon that the government agency is "very keen on how games like Plague Inc can be used to inform the public about health issues and raise public awareness of these issues."
For example, in easier difficulties of the game, text points out that those infected do not wash their hands. It's a simple reminder that failing to do something so simple could make you next on the food chain for a rapidly-mutating virus whose sole goal is to wipe out every human on the face of the earth. Remember that!