The word “mange” conjures up images of sickly dogs infested with a nasty, highly stigmatized skin parasite, which is contagious to other dogs and to humans. So it’s no surprise that many owners are aghast when their young dogs are diagnosed with puppy mange.
The first type of mange — the scary, nasty one — is sarcoptic mange, also known as scabies. It is caused by a vile parasite named, unsurprisingly, Sarcoptes. It is common in developing countries and in dogs anywhere who live in conditions of suboptimal care and hygiene.
Puppy mange is something different altogether. It also is caused by a skin parasite. However, the parasite, called Demodex, is ubiquitous. It is present on virtually every dog. Most puppies contract the parasite very soon after birth, possibly while nursing (although there is some debate about how puppies contract the parasite, it is widely agreed that almost all puppies do contract it). Demodectic mange (another name for puppy mange) therefore generally doesn’t otherwise spread from dog to dog — it is not possible for a dog to catch something he already has.
Puppy mange earned its moniker because most dogs’ immune systems are able to effectively prevent the skin parasites from causing any symptoms. However, in young dogs with immature immune systems, the parasite sometimes gets a bit out of control. Symptomatic puppy mange is most common in dogs younger than 18 months; however, dogs of any age with compromised immune systems may develop symptoms.
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