How to treat gravely ill?

[Super Earth President]

A survivor in my community is gravely ill and even occur mercy shot mission, but i have a lot of medicine and even a medical lab and few hours later i go back to the game and receive a notification that she is dead. I don't want this to happen again.

[NOCTURNE]

Fully upgraded medical tent, medicine, and a someone with medical background. If you have all of those, the chance of dying will be minimum. But still not impossible I think.

[Magic Mark]

Keep a close eye on sick survivors, make sure you have a high stock of medicine. Unfortunately gravely ill survivors are basically victim of any outcome. I've seen recovery but it's a slippery slope.

[Gritzenizer]

I dont really know what im exactly doing but I cannot recall a single death due to gravely ill in my breakdown session.