Almost all fish will jump, if they're frightened or there's something poisonous in the water that they want to get away from - especially if the tank isn't well covered.
Danios tend to hang out at the top of the tank, they're very fast, busy fish and IME they can and do jump out if they're spooked.
Yes it is possible that they CAN jump, but I have mine in an aquarium without a hood and they have never gone above the surface of the water. I'll admit that maybe I should keep a hood on the tank, but it doesnt really seem to be a problem.