Sarcoptic Mange

Sarcoptic Mange

Causative Agent

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Extensive loss of hair may occur in severe cases of sarcoptic mange. Mange is commonly found on wild canids such as this grey wolf.

Distribution

Geographic:

Seasonality:

Observed throughout the year but most commonly observed during winter months when hair loss can be life threatening.

Hosts, Transmission and Life Cycle

Hosts:

Infections found in humans (called "scabies"), wild and domestic dogs and cats, bears and mustelids.
Sarcoptic mange is commonly found on red fox, wolves, and coyotes in North America. It has been reported to occur in all three of these species in BC.
Mange in wild species predominantly affects younger animals.

Transmission and Life Cycle:

Mange is highly contagious, usually resulting from direct transfer of mites at any stage of their development.
Indirect transfer of mites may also occur from infected inanimate objects (mechanical transmission).
Populations of S. scabiei are usually highly specific as to their hosts - human-adapted populations spread more rapidly among humans, dog-adapted types spread more rapidly among dogs, etc.
The life cycle of S. scabiei is completed within burrows in the epidermis of the host.
Adult mites mate in small pockets near the surface of the skin.
After mating, female mites burrow through the skin by chewing and feeding on live cells or tissue fluid. Eggs are laid throughout the tunnel.
Hatched larvae pass through a nymphal stage and continue migration through the epidermis, becoming adults within 2 weeks of hatching.
Mites can remain infective without a host for extended periods; an important factor in the maintenance of the disease.

Signs and Symptoms

Animals:

Mange infestations are characterized by oily skin, crusting, hair loss, and scab formation.
Infections typically begin on elbows and towards the tips of the ears and can eventually involve large areas of the body.
Lesions result from physical damage to the skin, irritation caused by parasite excretions, and the allergic response of the host.
Lesions may be covered by thick fur but hair is often lost in characteristic patterns.
Affected skin is itchy and self- trauma may often be evident.
Poor body condition and listlessness may be observed in severely infected animals; for example, mangy wild canids (e.g., coyotes) may be easily approached.
Severely affected carnivores may scavenge with increased frequency.
Severely affected carnivores may ultimately die from complications with mange infection or exposure to the elements that results from hair loss in winter.

Humans:

Lesions usually occur at sites where contact was made with infected animals (e.g., hands and arms) and are usually short in duration. As in animals, skin becomes red, inflamed and intensely itchy.
Human infections from animal sources are short-lived and self-limiting.

Meat Edible?

There is no risk to humans since the meat from carnivores is not normally consumed.

Human Health Concerns and Risk Reduction

Rubber gloves and protective clothing should be worn when handling wildlife with skin conditions.
Applications of pesticides (acaricides) can be used to treat infected animals and people; however, repeated applications are necessary.

Samples for Diagnosis

Identification of the mite from deep skin scrapings or skin biopsy of the affected area.

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