Distemper is not contagious to humans. But distemper vaccines are often 5-in-1 shots, including parvo virus, adenovirus 2, parainfluenza virus, and sometimes leptospirosis. Lepto IS contagious to people. It is spread primarily through urine (walking barefoot in areas where dog has previously urinated). It can cause a host of rather horrible conditions, and can be fatal. Some vets do not vaccinate for lepto because it can cause vaccine reactions in the dogs and the true risk of transmission from dog to human is rather low in most areas. But the vets often know the areas and conditions where lepto can be a problem and may recommend vaccinating for it to protect the humans.
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