The Cure is humanity's last defense against a plague.
Once a plague becomes spotted, cure development will begin shortly after. Plagues can be spotted due to symptoms, increasing in chance of being noticed when severity rises. If cure progress is at 100%, development teams will rush to infected countries and begin to cure the infected. Once all of the infected have been cured, the game ends. Delaying the cure is very important (evolve Genetic Hardening 1 and 2 to slow research, and evolve Genetic ReShuffle 1/2/3, or evolve stifling symptoms such as Coma and Seizures to further delay research, or make the plague deadlier to kill off valued research contributors). Warnings will be issued when cure development has reached 25%, 50%, 75%, 95%, and lastly, 100%.
Due to the fact that the nano-virus is a microscopic robot that can't be cured with modern medicine, the Cure Broadcast is what takes the place of cure in the Nano-Virus plague type. What makes the cure broadcast different is the fact that it starts immediately when the game starts, even before the plague is spotted. The cure broadcast can be slowed down with the abilities Code fragment interception and Code segment interception. It can also be stopped with the tier 3 ability Broadcast interceptor overload for a few weeks, although it increases the effectiveness of the cure broadcast at the end of the duration.
When playing as a Necroa Virus, it is possible to have cure progress reach 100% and have all infected cured and still win the game. This is because zombies cannot be cured as they are already dead and can continue killing healthy people. The biggest threat to the Necroa Virus is either Z Com, or the research facilities Chernobyl, the Giza expedition, DarkWater, or PfiGlax, as Z Com can protect a select country from zombie invasion, and the research teams will create new weapons so Z Com can effectively combat zombies.
In the Simian Flu DLC, the cure is instead developed by Gen-Sys, the company which developed and accidentally released the virus. Once they admit that they created the ALZ-113, they will take over all cure research from governments. They may set up labs near ape colonies to gather data, as well as other countries with large ape populaces. If a Gen-Sys lab is successfully raided by rampaging apes, the cure progress will take a noticeable hit due to lost research.