the dog was not covered in thick/fleas like you put it. it had like five thicks or so and a couple of fleas. but it is strange, non of her other dogs had it. and the female was clean until the six week pregnant, and she had not meet other dogs. where did it came from we do not know. she did not want the pups to be infested as it is more difficult as you know to treat pups than adult. troy