Just watch My Secret Terrius on Netflix.
It is a Chinese soap from 2018. And if you go to Season 1, Episode 10, 53 minutes into it, then you get this:
Doctor: We must do more research but it looks like a mutant Corona.
Patient: Corona, then MERS?
Doctor: MERS, SARS, the common flu. They all fall in the same family with the same gene information. The Corona attacks the respiratory system. During the 2015 MERS epidemic, the mortality rate was over 20%.
Patient: But that’s not serious enough to be used as a weapon. Am I wrong?
Doctor: Like I said this is a mutant virus. Someone tweaked it to increase the mortality rate by almost 90%.
Doctor: What’s more serious is that the Cvirus has an incubation period of two to fourteen days. The virus was manipulated to attack the lungs directly within just five minutes of being exposed.
Patient: Is there a cure?
Doctor: There is no cure or vaccine available at the moment. They are hard to develop. But…