Toxoplasmosis is a disease caused by the parasite Toxoplasma gondii, which can be found in garden soil and raw meat.
Cats can get toxoplasma infection by killing and eating infected prey, the sort of little bird or mouse presents they fetch home. The disease is also passed on from cats to humans.
The only known definitive hosts for Toxoplasma gondii are members of family Felidae (domestic cats and their relatives).
Intermediate hosts in nature include birds and rodents.
If women become infected with Toxoplasma during or just before becoming pregnant, the protozoa can be transmitted to the foetus.
While not all babies infected in the womb will develop clinical signs of the disease, the infection can lead to miscarriage, stillbirth, or babies may be born with brain abnormalities or partial to complete vision loss. Up to 85% of children infected in utero will develop a decreased quality of vision, and while most symptoms are revealed within the first year of life, the disease can continue to develop until adolescence.
How to reduce your risk of toxoplasmosis from cats
If you’re pregnant, it’s important to take measures to avoid toxoplasmosis infection by:
• not emptying cat litter trays – if you cannot get somebody else to do it, wear disposable rubber gloves and wash your hands thoroughly afterwards
• changing your cat’s litter tray daily – it should also be thoroughly cleaned every day using hot water
• washing your hands thoroughly if you come into contact with cat poo
• wearing gloves when gardening (even if you do not have a cat) in case the soil is contaminated with cat poo
• washing your hands and gloves thoroughly after gardening or handling soil
• washing your hands thoroughly after handling cats and avoiding close contact with sick cats
A woman previously infected with the parasite who gets pregnant will probably not have a problem, because her immune system will keep the contagion in check, She will also pass that immunity on to her unborn child. However, first infection during pregnancy will cross the placenta, potentially leading to foetal death, stillbirth or problems in a newborn, including an enlarged head, cognitive deficits and almost certainly eye disease. Newborn babies born to mothers without previous infection are also vulnerable to the parasite.
Blindness from contact with cats
Infected cat litterboxes may indeed be a cause of the parasite affecting children. In humans, the infection usually causes no symptoms and resolves without treatment in a few months. In individuals with compromised immune systems, Toxoplasma gondii can reactivate to cause disease.
A toxoplasmosis infection that affects the eye usually attacks the retina and initially resolves without symptoms. However, the inactive parasite may later reactivate causing eye pain, blurred vision, and possibly permanent damage, including blindness.
Risks of this parasitic infection may be minimal yet they are real.