It seems there is "fake news"

and there is also "false news".
"Fake news" would appear to be something which  is not true at all. Someone  has "made it up". It's a lie. It never happened. It is deliberately designed to do harm, to ridicule, or to try and deny or gain support. It is the sort of news which gets "tweeted" and then reported in the mainstream media as the "real" thing. 
It is also the sort of thing that can make or break careers and bring about the rise and fall of political parties in an election. Yes, dangerous. Most of us like to think we won't get caught out by it - but we probably will at some point, even if it is just momentarily.
And then, even more disturbingly, there is what I would term "false news". It hasn't been made up as such. The "facts" would appear to be there. "Experts" and their "research" get quoted. "Scientists" and "people on the ground" get "interviewed". It all sounds convincing, very convincing - even very, very convincing. The problem is that the information we are being given is not true. Sometimes it is simply because the person reporting the story has misunderstood. Sometimes it is because they had preconceived ideas about an issue and they have sought information which will support those ideas. We are all guilty of that.
And there are times when people, especially journalists and reporters, will quite deliberately use their positions in an attempt to "inform" the rest of us by abusing the facts. They will take things out of context. They will quote only the "evidence" which supports their point of view. If we are already inclined to believe that point of view then it will only confirm it still further. We are all guilty of that too.
There are people who do this sort of thing because they genuinely believe they have a right and a duty to "inform" the rest of us. There are people who do it because they can and it gives them a sense of power over the rest of us.
All I can hope is that they had a sleepless night like the parents of the critically ill child who could not, for medical reasons, be vaccinated. It doesn't matter whether it is "fake" or "false" news. Both can lead to irreparable harm.