The whole thing was just * and can either be realistic because of how the desease flew considering the plot itself, but the implementation of each parts/scenes which just made the drama too complex to believe and understand that there's a lot of questions need to be addressed about what and how are things even settled in just 2 weeks. What makes the drama more unrealistic is... I'd better count them instead. Firstly, I've observed that the situation outside is too normal knowing that those people seems to having no problem at all and no fear you could expect them to be in the mid of a very serious desease. Secondly, how did they even handled the situation when the drugs has to spread, and I would've believed if the virus occurred in various places since the virus started with a capsule of drug supplement and no idea of where, which, or who are the people took the drugs . Thirdly, the drama seems to only focused in one setting and lacks details. Which is why maybe some of the viewers came with such negative opinions.
Overall, I didn't enjoyed watching the whole thing. The concept was interesting, the cast are also impressive, but the story and the flow of the whole scene was something that did not meet our expectations.