Environmental Decontamination
Ringworm spores can persist in the environment for a long time, perhaps 18 to 24 months. The spores are microscopic and can be spread easily by air currents and contaminated dust, and through heating ducts and vents.
To minimize environmental contamination in households where only one single pet cat is infected, the cat or kitten should be kept in a small, easily cleaned room (such as a bathroom) that does not have carpeting. The cat should be quarantined in this room until it has received oral antifungal medication for two weeks, and a minimum of four medicated baths. At this point, the cat can be given greater access in the home, ideally in uncarpeted and easily cleaned rooms.
Thorough and repeated vacuuming, and wiping of surfaces on a daily basis, should prevent the home from becoming contaminated. Cat beds and blankets should be washed daily in hot water and bleach. Bathrooms and smooth surfaces can be disinfected with a bleach solution (1 part bleach, 9 parts water). Routine cleaning and disinfecting should continue until the cat is considered cured of ringworm.
One veterinary dermatologist with extensive expertise in ringworm recommends the following decontamination protocol:
Initially…
• Discard all cat rugs, blankets, collars, brushes, and fabric toys
• Discard any cat objects that cannot be repeatedly scrubbed, vacuumed, and disinfected easily
• Purchase a new, inexpensive vacuum cleaner with hose attachments that can be thoroughly cleaned.
• Remove and clean all drapes and decorations. In multicat households, remove and clean all heating duct and vent plates, and install disposable house dust filters behind the duct plates before replacing them. This will keep spores out of the heating ducts
• If possible, put a fan in the window so that it draws air out of the room to the outside
• Vacuum all surfaces of the room
• Dust all surfaces and ledges with a disposable electrostatic cloth (like “Swiffer”)
• Scrub all surfaces with a detergent that is safe to use around cats. Rinse all surfaces well. Apply a 1:10 dilution of bleach to all non-porous surfaces. Leaving the bleach solution on the surface for 10 minutes is ideal.
• Using a portable dehumidifier is beneficial, because humid environments allow spores to remain viable.
Then, daily…
• Vacuum all surfaces and use the disposable electrostatic dust-trapping cloths to remove dirt and spores
And, weekly…
• Apply disinfectant to all surfaces. Disinfectants can be used daily, but they are harsh and irritating to people and cats. Weekly application is acceptable.