Protozoa 2 Flashcards
Toxoplasmosis
Toxoplasma gondii
Toxoplasma gondii - Hosts and distribution
Felines
Warm blooded animals can be PH
Cosmopolitan
Toxoplasma gondii - Life cycle
Enteroepithelial: Cats only Schizogony in jejunum and ileum Gametogony with development of oocysts Oocysts in feces for 1-2 weeks Extraintestinal cycle: All warm blooded animals Ingestion of sporulated oocysts Sporozoites are released, invade epithelium and enter circulation Enter tissues cells, become tachyzoites Become bradyzoites Enter chronic or carrier stage
Toxoplasma gondii - PPP
Rodent tissue with bradyzoites: 3-10 days
Sporulated oocysts or tachyzoites: 3-7 weeks
Toxoplasma gondii - Modes of infection
- Ingestion of rodents with bradyzoites
- Ingestion of sporulated oocysts or tachyzoites
- Transplacental tachyzoites
- Transmammary tachyzoites
- New intestinal infection from reactivated bradyzoites
Toxoplasma gondii - Pathology
Enteroepithelial: None
Extraintestinal: Brain, eye, lung, liver, LN, myocardium, intestine, pancreas, and abortions
Toxoplasma gondii - Clinical signs
PHs - The great imitator Ocular Respiratory Neuromuscular Cardiac Reproductive
Toxoplasma gondii - Diagnosis
Identify oocysts in fecal exam
Serologic test
PCR
IgM or IgG titers
Toxoplasma gondii - Treatment
Supportive care
Clindamycin
Pyrimethamine
Trimethoprim-sulfonamide
Toxoplasma gondii - Prevention and control
Change litter boxes daily
Cats shedding should be hospitalized
Prevent predation
Toxoplasma gondii - Public health
- Meat with bradyzoites
2nd deadliest foodborne illness - Ingestions of sporulated oocysts
- Organ transplantation or blood transfusion
- Transplacental transmission (tachyzoites)
- Goat milk (tachyzoites)
Giardiasis
Giardia intestinalis
Giardia spp. - Host and distribution
Mammals
Worldwide
Giardia spp. - Assemblage
A and B in humans
C and D in dogs
F in cats
Giardia spp. - Morphology
Trophozoite: Motile, teardrop or pear shaped, flagella
Cyst: Oval, 2 nuclei
Giardia spp. - Life cycle
Ingestion of a cyst
Trophozoites encyst in intestine
Pass into lower SI and large intestine and encyst
Cysts passed in feces
Giardia spp. - PPP
6-8 days
Giardia spp. - Pathology
Mechanical: Massive number and damage brush border
Biochemical: Toxins interfere
Bacterial overgrowth
Giardia spp. - Clinical signs
Highly variable Diarrhea (soft, greasy, and mucoid) Weight loss Flatulence Dry skin and poor hair coat
Giardia spp. - Diagnosis
Direct smear (trophozoites)
ZnSO4 flotation
Stain with Lugol’s iodine
Canine fecal ELISA (encystation protein)
Giardia spp. - Treatment
None aproved Fenbendazole Drontal plus Metronidazole MUST BATHE ON LAST DAY OF TREATMENT
Giardia spp. - Control
Baths
Keeping areas dry
Giardia spp. - Public health
Nah, but possible
Flagellates
Tritrichomonas foetus
Tritrichomonas foetus - Hosts and distribution
Cats
Tritrichomonas foetus - Taxonomy
Phylum: Protozoa
Subphylum: Sarcomastigophora
Tritrichomonas foetus - Morphology
3 flagella anteriorly and 1 posterior flagella
Tritrichomonas foetus - Transmission
Direct fecal-oral contamination with trophozoites
Tritrichomonas foetus - Pathogenesis
Inflammation in colon produces lymphocytic and plasmacytic enteritis
Mucosal crypt cell necrosis
Tritrichomonas foetus - Clinical signs
Chronic low bowel diarrhea
Diarrhea is malodorous, pasty to semiformed to watery, may contain blood and mucus
Flatulence
Weight loss
Tritrichomonas foetus - Treatment
Ronidazole (NDA by FDA)
Tritrichomonas foetus - Public health
Only one case, immunosuppressed
