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===Transmission===
 
===Transmission===
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Any of the three life stages of T gondii can infect warmblooded
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vertebrates, including cats and humans. Since
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tachyzoites are readily inactivated by gastric secretions,
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most orally acquired infections develop following the
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ingestion of bradyzoites or sporozoites. Coprophagy is
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uncommon in cats; the usual source of infection is the
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ingestion of T gondii bradyzoites during carnivorous
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feeding. Oocysts can generally be detected in the faeces
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from three days post-infection (see graph on the right)
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and oocyst shedding is usually completed by 10 to 21
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days post-infection. Only 20 per cent of cats infected by
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ingestion of sporulated oocysts will shed the organism;
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the onset of oocyst shedding is between 18 and 44 days
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post-infection, and the patent period is six to 10 days
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(Dubey and Lappin 1998).
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Transplacental infection occurs if a T gondii-naive
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woman or queen ingests T gondii during gestation. First
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trimester infections are rare but, when they occur, the
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sequelae are generally severe. In humans, stillbirth, abortion
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and severe CNS disease are common. In neonatally
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infected kittens, interstitial pneumonia, necrotising
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hepatitis, myocarditis, non-suppurative encephalitis and
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uveitis are commonly detected after necropsy and histological
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examination. In humans, the fetus is more likely
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to be infected if exposed during the second and third
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trimesters but the resultant disease is usually milder. The
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same may be true for cats. Previously infected women or
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queens are unlikely to transmit T gondii to the fetus,
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even if exposed during gestation.
    
==Signalment==
 
==Signalment==
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