Pediculosis (Lice)

Lice infestation is uncommon in dogs and cats. Lice are highly host-specific. They complete their life cycle on the host (14 to 21 days). Lice can survive off the host for only a few days. They are spread by direct contact or by contaminated brushes, combs, and bedding. The white eggs (nits) are cemented firmly to the hairs of the host.

The following lice species cause pediculosis in dogs: Trichodectes canis (biting lice), Heterodoxus spiniger (biting lice); Linognathus setosus (sucking lice).

Signs Clinical signs are variable. Animals can have no clinical signs and be parasite carriers. There may be inor skin inflammation only, alopecia only, pimples and crusting eruptions, anemia, weight loss and intense itch.

Diagnosis Demonstration of lice and /or eggs on physical examination (white, attached to the hair) (for example, using Scotch tape impression).

Treatment Parasiticidal dips, powders or shampoos are used once weekly for 4 weeks. Frontline flea spray is applied twice 2 weeks apart. Ivermectin may be prescribed for sucking lice as for Cheyletiellosis. The premises must be cleaned up: wash bedding, brushes, and combs. Treat all affected animals and other animals in close association with them.

References
1. Scott, Miller, Griffin. Parasitic Skin Diseases. In: Small Animal Dermatology, 5th ed., W.B. Saunders, Philadelphia, PA, 1995

Go Pets America recommends seeking the advice of your local veterinarian for the most appropriate vaccination program and for the diagnosis and treatment of your pet's health problems. For vaccination requirements please contact your state and local licensing authorities.