Bacteria and Parasites
Cat feces can potentially contain bacteria, as well as parasites such as roundworms or Toxoplasma gondii (T. gondii) which causes toxoplasmosis. These can cause health issues within people and can be particularly dangerous to those with immune system deficiencies or pregnant women. Roundworms can cause fever, bronchitis, issues with vision or asthma. Toxoplasmosis can cause headaches, sore throats and muscle aches. Pregnant women who contract toxoplasmosis can pass on serious health issues to their children including hearing loss, vision loss, mental retardation and in severe cases, death.
Once the feces are in the garden, the bacteria and parasites within the feces can begin spreading into the soil. Cats bury their feces, so the feces may go unnoticed. Gardeners who note unusual mounds or digging in their garden should suspect feces and use rubber gloves to prevent contamination. Transmission is possible by touching the mouth after handling the soil or flowers grown in the soil, or by eating unwashed fruits or vegetables from the contaminated garden.
It is not uncommon for people to assume they can add their pets’ feces to a compost pile, assuming that cat feces are simply another form of fertilizing manure. Unfortunately, this is not true. For sterilization to occur, your compost heap would have to reach 165 degrees Fahrenheit for five days, a situation which is extremely unlikely.
There is no sure fire method for preventing a cat from eliminating in a garden. However, cats prefer finer-grained soils. Therefore, placing a layer of mulch, bark or medium to small rocks may help deter the cat from using the garden as its personal litter box. Many commercially-available deterrents might also help. Furthermore, do not add cat feces to your compost pile.