Sarcoptes scabiei
National Veterinary Institute, Uppsala, Sweden
Sarcoptic Mange Mites are
tiny arachnids
(cousins of ticks and spiders) that are parasites
of mammals.
They cause the disease known as "mange" or
"scabies." These mites are tiny,
only 1/64 of an inch long. They are pearly white in color
and oval-shaped. They have spines on their bodies and legs.
They have no eyes. Sarcoptic Mange Mites
spend their entire life on their hosts.
The host is the animal that the mite lives on. Sarcoptic Mange Mites are
parasites of squirrels, rabbits, foxes, dogs, humans, and
many other mammals. Identification and
Diagnosis of Parasites of Public Health Concern The Internet Pathology
Laboratory for Medical Education Scarcoptic Mange Mites
use small suckers on their legs to hold onto their
hosts. After mating, female
mites burrow into the skin of the host. They use their jaws
and front legs to cut the skin. They mites tunnel in the top
layer of the skin only. Inside the burrow, the
female will lay eggs. She lays two or three eggs each day,
for up to two months. Mite larvae
hatch from the eggs in three or four days. They immediately
crawl out of the burrow onto the surface of the skin. The
will stay here, using the host's hair as shelter.
Both larvae and adult
mites eat skin cells from their hosts.
Once a larva has eaten
enough, it will molt
(shed its skin). After it molts twice, it has become an
adult. Adult mange mites mate on
the surface of the host's skin. The disease
caused by these mites, called "mange" or "scabies," starts
with a substance from the mites' bodies. This substance
causes an allergic
reaction in the host's skin, and it becomes very
itchy. When the host scratches
itself, it makes wounds that become infected by
bacteria.
The scratching also causes hair to fall out and animals with
mange will often have bald patches.
