Most cats infected with Toxoplasma gondii show no symptoms at all, but when illness does occur, the most common signs are fever, loss of appetite, and lethargy . More severe symptoms depend on which organs are affected and are more likely in kittens or cats with weakened immune systems (e.g., FeLV or FIV).
🐾 Key symptoms of toxoplasmosis in cats
- Fever — often one of the earliest signs.
- Loss of appetite — may lead to weight loss.
- Lethargy — reduced activity or weakness.
- Respiratory problems — pneumonia can develop, causing worsening breathing difficulty .
- Jaundice — yellowing of skin or gums if the liver is affected.
- Neurological signs — seizures, circling, head pressing, difficulty swallowing, personality changes, or loss of coordination .
- Eye inflammation — uveitis, abnormal pupils, blindness, or retinal inflammation .
- Muscle pain — muscle hyperesthesia (pain when touched) is reported in some cases .
- Diarrhea — usually mild and short-lived; occurs in a minority of infected cats .
🐱 How common is illness?
Most infected cats never show symptoms. Clinical toxoplasmosis is rare and usually appears when the immune system cannot control the parasite (e.g., kittens, FeLV/FIV-positive cats) .
🧪 When to worry
If a cat shows fever + lethargy + appetite loss, especially combined with breathing issues, jaundice, or neurological signs, a vet should evaluate them immediately. Diagnosis typically involves IgG/IgM antibody testing and sometimes imaging or tissue sampling.