Animal Scabies

 

Introduction

 

Transmission of animal scabies to humans is probably rare, because of the relative host specificity of the mites. However, recurrent exposure to animal scabies mites can produce troublesome and diagnostically puzzling lesions.

Many varieties of Sarcoptes scabiei have been incriminated, including the following.

1.   The mites causing sarcoptic mange in horses, cattle, buffalo, pigs, camels, monkeys, sheep and goats.

2.   Sarcoptes scabiei var. canis commonly causes transient skin lesions in those in contact with infested dogs. Exceptionally, scrapings from human skin have shown mites and eggs, and symptoms have persisted after contact with the animal has ceased. Affected animals have areas of scaling and hair loss on the ears, face and limbs.

3.   Notoedrescati, the cause of sarcoptic mange in cats, is almost unknown in the UK, but where it is endemic in the cat population, as in India and Japan, human skin lesions may occur.

 

Clinical features

 

Skin lesions resulting from contact with animal scabies vary in extent and distribution, according to the mode of exposure. The eruption is usually composed of small pruritic weals or papules, which are frequently excoriated, and resemble human scabies, but without burrows. Lesions from exposure to mites in dogs and in cats usually occur at sites of contact with the animal, principally the chest, abdomen, thighs and forearms.

 

 

Treatment

 

If contact with animal scabies is suspected, the diagnosis can only be confirmed by examining and taking scrapings from the suspect animal. Affected animals should be treated by a veterinary practitioner.

Human skin lesions are self‐limiting, and will resolve once exposure to the affected animal has ceased, or it has been treated. Despite being self‐limited, the skin eruption may be uncomfortable, and topical treatment such as 5% permethrin cream will hasten recovery. Oral ivermectin (200 μg/kg single doses) has been used, as well as topical corticosteroids, menthol preparations, and oral antihistamines for symptomatic relief.