Yes," Harry replied. "The Death Eaters have tried to use him to find this place, to find me, every time they've caught him. They've hit him with tracking charms and sent him on his way, hoping he'll lead them here; they've infected him with diseases, hoping he'll return home and spread them to everyone; they even gave him a suitcase nuke once. Imperius Cursed him, made him think he was a Muggle returning from a business trip. I was actually quite impressed with that one."