Zoonoses of Carnivores Flashcards
How are Toxoplasma oocysts excreted from cats?
Immature
How long do Toxoplasma oocysts take to sprulate in the soil?
1-5 days
How are humans exposed to oocysts? (3 ways)
Contaminated soil or water
Produce
Ingestion of tissue bradyzoites in undercooked meat
How can Toxoplasma bradyzoites in meat be rendered noninfectious? (2 ways)
Freezing for >7 days
Cooking
How does Toxoplasmosis present in people?
Asymptomatic in immunocompetent people
Sever problems in people with AIDS or people who are pregnant.
How can Toxoplasma risk be minimized?
Reduce human exposure, no good control program for cats
What are larval migrans?
Larva migrating in the paratenic hosts
What is human toxacariasis considdered?
A “neglected” tropical disease
What age group is at risk for toxocariasis?
Children between 1-4yoa (pica and geophagia)
What is the most common form of toxocariasis?
Visceral larval migrans
How can you prevent toxocarasiasis?
Reduce reservoir via anthelmintic treatment of cats and dogs.
What percentage of soil samples from parks and sand pits may have Toxocara?
20-40%
What species can function as an alternate definitive host for Baylisascaris procyonis?
Dogs
What 3 cestodes use humans as a definitive host?
Beef and pork tapeworm (T. saginata and T. solium) Fish tapeworm (Diphyllobothrium) Dog tapeworm (Dipylidium caninum)
How are humans infested with cestodes?
By eating intermediate host tissue (definitive host)
By ingesting larvated eggs (intermediate host)
What two cestodes are humans used as an intermediate host?
Echinococcosis (E. granulosus, E. multilocularis)
Cysticercosis (T. solium)
What are symptoms of cestode infection?
Depends on organ/system affected
Anaphylactic symptoms follow cyst rupture
What are 3 major points of E. granulosus infection?
Hydatid cyst disease
Liver
May develop in brain
What are 2 major points of E. multilocularis?
Alveolar cyst disease
Often liver, secondarily into lungs
What is the reservoir for all species of Echinococcus?
Canids
What is the definitive host for E. granulosus?
Dogs and wolves
What is the intermediate host for E. granulosus?
Sheep, moose
Where does man fit in with E. granulosus life cycle?
Aberrant intermediate host, infected by ingestion of eggs
T/F: Most of the USA is endemic for Echinococcosis.
False, most of USA is non-endemic.
What is used to treat dogs infested with E. granulosus?
Praziquantel
What are 3 ways that cystic echinococcosis is controlled?
Preventing infestation in dogs
Condemnation/disposal of infected offal
Preventing transmission to people (education and hygiene)
What is the natural cycle of alveolar echinococcosis?
Between foxes and rodents
What is the fatality rate for untreated alveolar echinococcosis?
50-75%
Where can alveolar echinococcus be found?
Throughout the northern hemisphere
What are 5 ways that alveolar echinococcus is controlled?
Anthelmintic treatment of dogs Reduce exposure of domestic pets to rodents Treatment of foxes (baiting) Education Stray dog control
