Toxoplasmosis

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Toxoplasmosis

• Protozoan Parasite
• Toxoplasma gondii

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Historical Facts--Toxoplasmosis

• 1. First described in 1908, in material from a
  small rodent, the gondi.
• 2. Rediscovered in 1935 in the brain tissue of
  guinea pigs used for encephalitis experiments.
• 3. In 1939 it was found as the cause of
  encephalitis and chorioretinitis in a 31 day old
  infant. This stimulated interest in the disease.
• 4. In 1969 infective cysts were detected in the
  stools of cats experimentally infected with
  toxoplasmosis from mouse tissue.

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Toxoplasmosis

• Domestic cat and other Felidae are the definitive
  host
• Vertebrates are the intermediate host
• 1. amphibians
• 2. fish
• 3. reptiles
• 4. all warm-blooded animals including man

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Toxoplasmosis Cycle
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Toxoplasmosis Transmission

• 1. Carnivores usually infected by the ingestion
  of bradyzoites encysted in another intermediate
  host.
• 2. Herbivores usually infected by the fecal-oral
  route. Ingesting sporulated oocysts shed by
  infected cats.
• 3. Transplacental Transmission. Tachyzoites
  multiply within the placenta and spread to the
  fetus.

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Toxoplasmosis Tissue Cyst
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Toxoplasmosis Tissue Cyst
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Toxoplasmosis in Cats

• Any organ system can be infected
• Many infections are mild and self-limiting
• Cats shed oocysts for only 1-2 weeks following
  infection. Oocysts sporulate and become
  infective in 1-5 days.
• Disease can cause CNS and Ocular problems, liver
  disease, fetal death and abortion.

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Diagnosing Toxoplasmosis

• Detecting oocysts in the stool
• Serological TestingELISA tests
• IGg and IGm
• Titers of IgG can last for years
• Titers of IgM usually persist for only 12 weeks
  unless cat has FELV

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Toxoplasmosis oocyst
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Toxoplasmosis Treatment

• Antibiotics
• Clindamycin
• Potentiated Sulfa Drugs

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Toxoplasmosis in Humans

• 1. Majority of cases are asymptomatic
• 2. Mild fever, sore muscles swollen glands and
  lymph nodes, similar to mononucleosis
• 3. Immunocompromized individuals are at greater
  risk. HIV patients, Organ transplant patients,
  people on chemotherapy
• 4. Pregnant womens fetus are at risk if the
  mother acquires the infection during gestation.
• 5. CDC estimates 400-4000 cases of congenital
  toxoplasmosis per year.
• 6. Blindness, Hydrocephalus, seizures and mental
  retardation are common
• 7. 750 human deaths per year make it the 3rd
  most common lethal food poisoning.

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Toxoplasmosis

• Human/Congenital Transfer

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Toxoplasmosis Zoonosis Control

• Clean the liter box daily (it takes 1-5 days for
  the oocysts to sporulate and become infective)
• Cook all meat and fish thoroughly
• Pregnant women should use caution when exposed to
  cat liter or gardening.
• Have another person clean the liter box
• Wash hands and counter top thoroughly after
  preparing raw meats and fishes
• Immunocompromized individuals should use the same
  caution with cat litter and cooking of meats.
• Pork is reported to be the most common meat
  infected
• Hunters should wear gloves when dressing wild
  animals

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Pregnancy and Your Cat

• 1. What should I do with my cat now that Im
  pregnant?
• 2. Is testing of my cat practical?
• 3. Should I be tested for exposure to the
  disease before my child is born?