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instances, a site visit and cultures of the environment can also be informative.

EnvironmentaI treatment

A contaminated environment is an under-recognised reservoir of infection, particularly in multiple cat households, colonies and catteries. Decontamination should start with aggressive cleaning. Ali possible fomites should be removed and destroyed, if possible. These include toys, bedding, cat scratching posts, brushes, etc. Ali organie materiał should also be removed, preferably by vacuuming. Ali surfaces will need to be vacuumed: ceilings, floors, walls, ledges, air vents, etc. Any place where cat hair or scalę can accumulate is a potential source of infection. Next, these surfaces should receive a triple cleaning with an all-purpose, detergent solution that is safe to use around cats. Heating and air-conditioning appliances will also need to be cleaned and specialist cleaners may need to be called in. Care should be taken to ensure that there is adeąuate ventilation in the colony or cattery. Once cleaning has been completed, air filters can be fitted, which can be changed weekly to reduce futurę contamination.

After the environment has been cleaned, an antifungal solution should be applied. These products will not work in the presence of infected organie materiał. Any surface that cannot be thoroughly cleaned should not be treated. There is no antifungal product effective against Microsporum canis following one application which also maintains a residual effect²⁰. Several applications lasting between 10 and 20 minutes are necessary to achieve optimal efficacy. According to one in vitro study using infected cat hair, household bleach in 1:10 or 1:100 Solutions, chlorine dioxide, glutaraldehyde and potassium monoperoxysulphate are the most effective agents²⁰. Enilconazole is also a very effective disinfectant and available as a spray or fogger¹. Contaminated catteries or colonies should be cleaned every day and disinfected every other day. Most antifungal disinfectants are irritating to the mucous membranes of cats and people. Therefore, cats should not be allowed contact with surfaces that are still damp. As spores are readily carried in the air and can stay infective for a long time, environmental decontamination should be continued for several months after the animals have been cured. If a colony is open to visitors, accepts cats on breeding loan, or is involved in shows, these decontamination procedures should be performed routinely.

Preventing transmission to other animals and people

Preventing transmission to people and other cats in colonies is also important. Fungal cultures should be performed on all cats to confirm infection. Clinically affected cats should be isolated. In a colony, it is better to assume that all cats are infected. It is actually rare for infection to be limited to just a few cats. Treating only selected animals usually results in the colony becoming seeded with asymptomatic carriers. Cats should not be shown, sold, or sent on breeding loans. No new animals should be accepted into the colony, which should be closed to outside visitors. Long-haired cats should be clipped and treated topically once a week and vaccination may or may not be indicated for all cats. These measures may not be feasible in large establishments. Systemie antifungal treatment is recommended for all cats (except pregnant queens which should not be treated before the kittens are bom) and should be continued until fungal culture, carried out weekly, is negative on two or three successive occasions. Although Wood’s lamp examination may be helpful in monitoring therapy, fungal culture is morę reliable for giving the colony the all-clear. Contact between cats should be limited. Animals should not be allowed to wander freely and should be restricted to their cages. Providing thorough flea control and addressing all other causes of pruritus is also important as pruritus will cause damage to the skin, facilitating penetration of spores. In addition, scratching cats shed morę hairs into the environment. Finally, fleas, themselves, are capable of harbouring and transporting fungal spores.

Preventing recurrence

Once dermatophytosis has been eliminated from a colony, the infection may be re-introduced by contact with infected cats, contaminated fomites, or part of the environment that was incorrectly treated. A negative fungal culture should be obtained from all new cats before introducing them to the colony. While awaiting results, these cats should be isolated. At shows, cats should, when possible, remain in their cages and these should be covered to prevent airbome spread of spores.

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fogger not available in UK, translator’s notę.