The blast effects (which is all the question as worded asks about) would be the same as the blast effects of a weight of TNT identical to the nuclear bomb's yield (by definition).
However a nuclear bomb has additional effects that the TNT doesn't, but as this question only asked about blast effects, I won't visit them.
harmfulness of virus
Yes the tsunami did trigger the nuclear blast because the water got into the nuclear reactor and buggered it up
no
yes, thousands
Blast, always blast.
Correct answer is blast effect
none
35km
A direct nuclear blast - nothing. However it is said that cockroaches would possibly survive radiation where other animals would be killed.
Twinkies
Blast
blast