Hair falls out with a light tug, and the end of the hair will be coated with scurf / dead skin. There is often a white bloom to the skin.

Thinning hair with bald areas only in the area of infestation, often with an inverted V-shape in the middle of the back.

Heavy, gritty scurf (like dandruff).  There may be white tide marks on the ears and / or jagged edges.

Hair shafts broken off half way down to the root around the area of infestation.

Very greasy hair and / or skin that is red (rather than a healthy pink colour). Often feels hot to the touch.

Hair will not come out when lightly tugged.

Intense scratching, biting and irate squeaking. Nerves are often affected and if you touch them around the hip area they will often turn round and try and bite you.

A little bump / scab on the skin surface - this is the tiny mite just below the skin. Sometimes you will see spots of dried blood caused when the mite is burrowing under the skin.

If the infection is bad, there may be thick crusty patches of skin, extensive hair loss, considerable scratch lesions, and the guinea may even be fitting.

Intense scratching / irritation which may lead to fitting if left untreated.