
First thing I would want to know is did the puppy receive a vaccination prior to the itching starting up..??
If so which brand of vaccine was given...?? How many shots were given...?? If the puppy reacted within several days of the first vaccine was the vaccination schedule stopped immediately.....or did the vet continue to give the further shots....??
What diet was the puppy on....??
The etiology is not fully understood but it is thought that some dogs....and some breeds....do have a genetic predisposition to the condition, with environmental factors providing the necessary additional trigger....but....there are many, many research papers showing a link between allergies and vaccines. In 1983 Frick and Brooks published a paper to show that inhalant allergies (such as atopic dermatitis) have developed in dogs when vaccinated with distemper, hepatitis and leptospirosis vaccines. The allergic individuals suffer chronically irritating skin inflammations and other organs may exhibit signs of hypersensitivity causing for example conjunctivitis or rhinitis.
Homoeopathic vets treat a large proportion of skin problems as "vaccinosis" (a morbid reaction to vaccines).
As a breeder (or breed council) you really do need to monitor these reactions closely in your puppies and breed and if there is even the slightest suspicion that a vaccine or drug has caused a reaction then it needs to be reported and investigated. Otherwise it allows slurs against a breeder....when it is quite possible...and in my opinion highly likely....that the vaccine or drug has caused the reaction in the first place.