But Ebola (virus) only has RNA, no DNA.

I would suggest making a mene with a virus that has a DNA genome … (eg hepatitis virus)
… or just use RNA (“RiboNucleic Acid”) as the example, humans need it just as much to function as DNA (“DeoxyriboNucleic Acid”).

(But sure, Ebola needs our DNA in the sense that otherwise we wouldn’t be alive. But so do nuclear weapons in order to kill humans.)