Slightly related, but this morning I was reading a news story on a local website (I live in Eastern Europe, in a country that is a EU and NATO member) about the whole US budget debacle in the House Representatives, and the first (and until now only) comment was mentioning Ocasio Cortez (D) in a derogatory manner, even though she had not been named in said article at all and people around this part of the world don't have the slightest clue of who she is.
Sure enough, I soon found a recent article about Ocasio Cortez on the (in)famous sputniknews.com website where she was criticized for I don't know exactly what (I'm not going to link it here, don't want to give them the traffic) and then it all made sense, it looks like the Russian shill accounts have a new target now. In other words the hybrid and propaganda war is indeed real.
https://mobile.twitter.com/JulianRoepcke/status/108109176879...
AfD actually did influence German politics and policy making a lot, and public debate even more so, in my humble opinion.
From what I have seen, AfD is also a lot more "broadly extremist" than UKIP, but I am very probably pretty biased, being from Germany and having consumed far more German news than British.
Trouble is, the UK political scene is currently entirely populated by people who lack the competence to realise there is anything wrong with their own strategies. (All of them, including the groups I used to consider ‘my side’).
So, they might be relevant by default.
They are still going under different leadership, focusing on other typical right-wing issues. Depending on how things go with Brexit they might well come back into the limelight this year.
AfD avoids making any commitment on what they really want to do[0], they only proclaim that everybody else sucks. They'd be a pretty sorry bunch if they'd end up having to govern.
[0] and I doubt that there's any coherent agenda to that end. At the time where they have to agree on something, I expect a huge fall-out between the camps within the party.