My son lives in Montana and has what we think is a parasite in his body, he says the larva is coming out his skin which starts with a black spot and then it open up to release the larva, it is all over in his hair, back feet . he is using powder to kill them but is has gotten worse the last few day, Someone told him it is called magnalin or something like that….I have been looking on the internet but can/t pin it down