Containment of Mortis
What happened in Mikhaliv was ultimately contained, but that didn't matter to those who still lived inside the city's boarders. It was considered an inevitable death sentence, and the researchers knew that, but it didn't make anyone inside feel better.
The first to fall were most vulnerable populations, the elders and the young, helpless as their withered immune systems turned against the very thing they were supposed to protect, the flesh cracking from the fluids constantly leaking out, before finally becoming unrecognizable in life as they were in death. They were the lucky ones, as they didn't suffer the most infamous symptom of the Mortis.
Later on, with the quarantined pathogen mutating in containment, those in their prime started falling, and that's when the more insidious symptoms of the Mortis started manifesting-namely that those who were not quite dead, but suffering immense pain, would turn into nothing more than animals, attacking their surroundings for short bursts of time, sometimes for hours at a time, until they slowly expire, sitting in their own infected biomass killing them from the inside out.
For the researchers, it was a grisly task, but offered up a rare oppertunity-the chance to study a neurological, airborne pathogen in a contained area. The results that we know of came from the many expeditions and the findings that they wrote down. Unfortunately, containment was slowly proving to be insufficien, and as a result, those that weren't actively involved with field research were evacuated as an even longer containment zone was erected, trapping those who knew what would happen to them, but arguably saving the contin from turning into a dead zone.
One wonders at what point was the sunk cost fallacy worth it, considering that, to this day, the Highlands are No-Man's Land, for fear that this pathogen will spread death once again, millennium after the civilization that contained it fell apart into smaller sects due to economic issues.