Parasites2 Flashcards
(42 cards)
Toxocara canis
• “Roundworm” “Ascarid”
• Adult parasites are ~ 10-18 cm
• Eggs are round w/ a thick, pitted shell
-Fecal oral contact transfer.
-Prefers GI system.
-Can migrate to lungs, liver, fetus, or be transmitted by milk
Importance of Toxocara canis
-high percentage of pups infected, death in pups 2-3 wks old (lung damage), vomiting, diarrhea, visceral larva migrans-
Diagnosis and Control of Toxocara canis
- Diagnosis- Eggs in feces, worms in vomitus
* Control- Treat infected dogs, remove feces
Life cycle of Toxocara canis
- visceral migration occurs in pups < 3 mo.
- Old, tissue dormancy occurs in older dogs and mobilization to uterus is seen in the last trimester of pregnancy
Visceral Larva Migrans
• Damage to the body’s internal organs caused by a migrating roundworm larva • Causative parasites: o Toxocara canis o Toxocara cati o Baylisascaris procyonis
Syndrome of Visceral Larva Migrans
o Human– asymptomatic or mild signs
fever, cough, skin rash, abdominal pain, CNS abnormalities, ocular dz.
o Animal– malnourishment, vomiting, diarrhea
Incubation and Mortality of Visceral Larva Migrans
- Incubation period is weeks to months
* Mortality: Low
Occurrence and Transmission of Visceral Larva Migrans
- Occurrence - More of a problem in warm, moist climates
* Transmission- Ingestion of infective worm eggs
Diagnosis and Treatment of Visceral Larva Migrans
- Diagnosis- CBC, serology, ELISA test
* Treatment- Antiparasitics
Control and prevention of Visceral Larva Migrans
o Personal hygiene
o Regular deworming of dogs and cats
o Prevent contamination of soil w/ dog, cat feces
o Keep children from eating dirt or putting dirty objects in their mouth
Trichuris vulpis
• “Whipworm”
• Adult parasites are 4.5-7.5 cm long, thin anterior and thick posterior
• Eggs are barrel-shaped w/ transparent plugs ate each end
Worms are large on one end and taper down
• Adults live in LI (colon, cecum). Adults hide in cecum and only sporadically shed eggs
Very hard to diagnose and treat.
Diagnosis and Control of Trichuris vulpis
- Diagnosis- Eggs in feces, don’t typically see adults
* Control- Treat infected dogs, remove feces. Fecal-oral contamination.
Taenia pisiformis
• “Tapeworm” • Adult tapeworm is up to 200 cm long • Eggs passed w/in proglottids in the feces-NO cluster, no packet. YES hooklets- Small Intermediate host is rodent or rabbit Individual eggs
Importance and Diagnosis and Control of Taenia pisiformis
- Importance- diarrhea, intestinal obstruction, damage to intermediate host
- Diagnosis- Proglottids in feces/ perianal area
- Control- Prevent access to intermediate host, treat infected dogs
Hydatid Disease
- Disease caused by ingestion of tapeworm eggs
* Causative organism: Echinococcusgranulosus
Syndrome of Hydatid Disease
o Human– asymptomatic
o – presents like a slow growing tumor in an internal organ
o Animal– subclinical
Incubation and Mortality of Hydatid Disease
- Incubation period is months to years
* Mortality: 50-75%
Occurrence of Hydatid Disease
o Rural areas of northern hemisphere
o Sheep-raising areas of the SW U.S.
Diagnosis of Hydatid Disease
o Fecal flotation
o Recovery of tapeworm after administration of taeniafuge
Treatment of Hydatid Disease
Antiparasitics, surgical resection of cyst
Control and prevention of Hydatid Disease
o Regular deworming of dogs for tapeworms
o Prevent dogs from eating viscera of intermediate hosts
o Wash food potentially contaminated w/ dog feces
o Practice good personal hygiene
Taeniasis
• Tapeworm infection acquired from eating infected beef or pork
• Causative organisms:
o Taeniasaginata
o Taeniasolium
Syndrome of Taeniasis
Human– usually asymptomatic
o perianal irritation common
o – weight loss, abdominal pain, GI disturbances
o Cysticercosis- formation of cysts outside of the GI system
Animal– subclinical
Incubation and Mortality of Taeniasis
- Incubation period is 8 to 14 weeks
* Mortality: usually none, cysticercosis possibly fatal w/o treatment
