I don't think the ET's who are aiding things behind the scene would unleash viruses to wipe out humanity-I believe we're in a school and 'they' are 'stage hands' but I think there are factions of ET's who might. Some one unleashed the black plague and others over the centuries-I believe that when the world gets too evil then these things happen-but then again;

'Redfern also revealed insights he received from a man who claimed to be the custodian for secret documents held by the US government. According to this man, the space suits worn by the ETs were considered biological hazards and that, when worn by a person, their thoughts mirrored those of an alien, resulting in a hostile perception of the human race. "It was like the person had a unique window image of the alien mindset, almost like a hive mind," Redfern recalled learning about these suits, "it created a lot of panic within the person, themselves, and they couldn't wear them for long." This interface between the mind and technology, Wood posited, may provide greater understanding as to how UFOs are controlled by their ET pilots'

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