The Kopp-Etchells effect is rather poorly documented. It's only just been named during the Iraq/Afghanistan wars, and I haven't found too many research papers on it to date.
"Napoleon attacked by rabbits" so I had to go google search it. "The story of Napoleon being "defeated" by rabbits during a hunt in 1807 is a humorous anecdote, but it's not a confirmed historical fact, though it is mentioned in General Thiébault's memoirs. "