Expert: Dr. Louis N. Gotthelf - 12/6/2008

Question
Dr. Gotthelf, I recently rescued a shelter puppy. He is now 13 weeks old, current on his vaccines and worming and heartworm treatment and flea and tick treatment, and will be finished with his 4 sets after two more sets of shots. When I brought him home he developed a slight cold and a runny nose. I took him to the vet and he said it was not a concern back then and to see if it clears. Well, it was just a minor cold and it cleared in about one week. Then I discovered he had roundworms and I got the appropriate wormer from my vet and have been on a worming schedule as instructed. He also seemed to be very scared of loud noises and the new environment and being away from his litter mates and mother. To add to all of this, he is now being treated for a minor eye infection and being treated with zymox for his ears (he does not have ear mites but the vet wanted to treat anyways because the ears were always dirty). Ever since treatment, I have no longer seen any worms, his eye is much better, and his ears are now spotless. However, at times he does still seem scared of the new surroundings and noises. He no longer has the cold. He is currently 13 weeks, 11.2 lbs, male, bully breed mix. Last week when I took him in for his second set of shots I informed the vet of some thin spots of hair I noticed. He did a skin scrap and saw Demodectic mites enough to say he was positive for Demodectic mange. At that time it was only small spots on two of his legs. I was sent home with the goodwinyl ointment to apply to the spots and any new spots until he recovers. We have not done dipping or medicine yet in hopes of his immune system taking over. The vet exaplined all about the mange to me but I had some other questions. I recently lost a previous pet to a serious inflammatory disease and so I am rather concerned about every little thing that comes up with my new puppy because losing the other pet was very hard on me and I do not want to go through that again. I know that it is not uncommon for puppies to get the demodectic mange because they have developing immune systems. The thing that concerns me is that I read a few stories about puppy having genetic defects where they never get over the mange and have to be put down. My puppy is not that bad right now but he has develop a total of around 8 spots on his body. First, considering he had a minor cold, was visibly stressed when he was seperated from his litter mates and mother, had roundworms, is still settling in his new family, had a minor eye infection, and had ear issues, could these events be enough to break his immune system down enough to let the demodectic mites take over? Is it more likely he is simply stressed and weak from all of the issues enough to let the mites take over or is it more likely he has a defect in his immune system? Also, if he does have a defect in his immune system does that mean he will likely need to be put down if the mites are not under control or is there a treatment for a weak immune system? Finally, is there anything I am not doing I should be to help him in any way whether it be medicine or de-stressers? He is so special to me even though I have only had him for 5 weeks. The lose of my other pet was so stressful on me and without my new friend I dont think I would have been able to move on as I have. Any help would be great. I read some things like 95% of puppies with demodectic mange recover and around 5% do not recover, is this also true? Thanks so much for any help.

Answer
You have asked many questions that can only be answered with time.  Yes most pups recover from mange.  The problem in puppies is not the breakdown of the immune system with stress, but that it has not fully developed until they are a year old or so. In older dogs that break with mange, it is stress related.  So providing good nutrition and health care, the puppy will develop normally.  Some dogs are genetically predisposed to a weak immune system, so those are the 5% you mentioned.  Ask the breeder if there are any chronic demodex dogs in their lines.  That should give you some insight into the genetic issue.