An interesting take. I had not considered this aspect. The liberal scientific and political elite have been wanting to significantly reduce the world's population. Not going to help property values though. If someone tries this they better hope no additional stressors occur as I believe small pox would take out half the population of the world.
http://www.who.int/mediacentre/factsheets/smallpox/en/
The disease, for which no effective treatment was ever developed, killed as many as 30% of those infected. Between 65–80% of survivors were marked with deep pitted scars (pockmarks), most prominent on the face.