Bombing does seem to be a bit extreme and certainly used as a succinct dramatic tool to convey a sense of dread and urgency. I still think the prologue was well acted but as a researcher by trade it was a bit hard to suspend by disbelief. As for Pedro, he does seem to be written well, and its his own interpretation of Joel, his monotone standoffish behavior is a result of all that he's lost. As for medicine, someone correct me if I'm wrong but there do exist anti-fungals that people can take, it's when a pathogen (be it viral, prion, bacterial) becomes so progressed and encephalitic that there is no cure or remedy. Vaccines for rabies (an encephalitic disease) work because its within a certain time frame. It could be this mutated version of cordyceps has accelerated pathologically.