True to their promise from last year, the developers of Plague Inc have released a free DLC for owners of the original game about finding a cure to a global pandemic, rather than being one. "Created with the help of world health experts from all over the world including the WHO, CEPI and GOARN, Plague Inc: The Cure is an engaging and timely simulation of a global disease response," say Ndemic Creations in the game's description.
It's full of brand new game mechanics over the base Plague Inc scenarios, and they're pretty neat. Players do work like hunting the disease with research teams, controlling the outbreak with social programs, supporting those controls with economic programs, and ultimately develop a vaccine that must be researched, manufactured, and distributed. All of those steps are reliant on global cooperation between countries.
The DLC will be free "for all Plague Inc. players until COVID-19 is under control." So you've got some time to snag it, but not forever, I hope. You can find it on Steam.