Curse of the Werefleas: Bob and Barry's Lunar Adventures - Bartram, Simon Series

When a big, hairy asteroid clips Bob's beloved Moon, it takes him and his dog, Barry, ages to clear up the itchy dust. Under a microscope all becomes clear - the dust was actually thousands of werefleas, travelling across the galaxy, turning planets and asteroids into hairy, scary, werewolf-infested places with their cursed bite!