39 (241)

Pediculosis

Aetiopathogenesis

Pediculosis is now rare in the cat and seen only in kittens or adults kept in poor conditions ^u. It is caused by Felicola subrostratus, a wingless insect of the suborder Mallophaga and family Trichodectidae (Table 3 : 2). Its life cycle lasts, on average, 21-30 days and takes place entirely on the cat ³. Felicola subrostratus is host-specific to the cat and therefore poses no risk to man.

Clinical features

The principal areas affected are the face, pinnae (Figs 3 : 24) and back. Non-specific skin lesions are characterised by a duli coat, scaling, papules and crusts. Sometimes, a true miliary dermatitis is seen. The degree of pruritus is variable⁶.

Diagnosis

Diagnosis is based on finding lice and nits and identifying them microscopically (Table 3:1) (Figs 3 : i,j). Treatment

Classic insecticide treatment (e.g. fipronil ** given twice monthly for 4-6 weeks) generally gives good results.

hermectin * (200-400 pg/kg), given once or twice (4 weeks apart), by subcutaneous injection, gives reasonable resultsIt should not be given to cats less than 4 months old.

When groups of cats are affected, ivermectin is the treatment of choice. The environment should also be cleaned thoroughly

Flea infestation

Aetiopathogenesis

Flea infestation is especially common in the cat. 95% of fleas isolated from cats are Ctenocephalides felis felis. Depending on the cat’s life style, other less specific species of flea may be found: Ctenocephalides canis, Pulex irritans, Archaeopsylla erinacei (hedgehog flea), Spilopsyllus cuniculi (rabbit flea) and Echidnophaga gallinacea (bird flea) (Table 3 : 2).

Flea infestation may cause skin disease through the irritant, non-allergic action of flea saliva. Immediate and delayed hypersensitivity reactions to salivary antigens are often responsible for producing flea allergy dermatitis (FAD).

Clinical features

Simple flea infestation may cause slight pruritus, a few papules and light scaling '.

Flea allergy dermatitis (FAD) is characterised by a pruritic dermatosis affecting the rear half of the body. Clinical aspects are variable: symmetrical alopecia and miliary dermatitis. Morę rarely, FAD presents as eosinophilic plaques, linear granuloma or facial pruritus

A seasonal pruritic dermatosis of the pinnae has been reported in Australia and appears to be associated with Spilopsyllus cuniculi

Diagnosis

Diagnosis of simple flea infestation is based on finding fleas and their faeces and identifying them microscopically (Table 3 : 2) (Figs 3 : k).

Treatment

Flea control is now morę straightforward, thanks on the one hand to the development of adulticides with enhanced residual activity that are virtually non-toxic to mammals, and on the other hand to Insect Growth Regulators (IGR) which provide almost all we could wish for in an integrated control programme. Strategy should involve selective use of several products, given simultaneously or

* This product is not licensed for use in the cat and responsibility for its use falls on the prescribing veterinary surgeon.

** This product is not licensed for this indication in the cat and responsibility for its use falls on the prescribing veterinary surgeon.

3.101