Nematodes Flashcards
What zoonotic agent is this describing:
Complex, multicellular pathogens, male and females with their own reproductive tracts, can produce a variety of different types of offspring (undeveloped eggs, larva inside egg, or live larva) depending on the genus and species
Nematodes
What zoonotic agent is this describing:
Complex, multicellular pathogens, male and females with their own reproductive tracts, can produce a variety of different types of offspring (undeveloped eggs, larva inside egg, or live larva) depending on the genus and species
Nematodes
What agent is this describing:
- Route of K9 infection - Oral-larvated egg, transplacental, paratenic host
- Hepatic, lung, and tracheal migration (somatic larval migration can be associated with clinical signs, liver and respiratory signs due to host inflammation to tissue damage caused by migrating larvae, immunity, encystment, larval leak during waning immunology
Toxocara canis
What agent is this describing:
- Oral-larvated egg, paratenic host
- Hepatic, lung, and tracheal migration (somatic larval migration can be associated with clinical signs, liver and respiratory signs due to host inflammation to tissue damage caused by migrating larvae, immunity, encystment, larval leak during waning immunology
(larval stages will undergo migration)
Toxocara cati
What agent is this describing:
- Route of infection, L3 skin or oral, transmammary
- Use migration through somatic tissues. Skin lesions associated with migrating larvae, immunity, encystment, larval leak during waning immunology or during early lactation, and L3 in milk
Ancylostoma caninum (hookworm dog)
Which roundworms of dogs, cats, small mammals are zoonotic?
- Toxocara canis
- Toxocara cati
- Baylisascaris spp. (B. procyonis - raccoons)
A rare inflammatory condition of the eye caused by local reactions to the larva of Toxocara species
Ocular larva migrans (OLM)
An infection caused by parasitic roundworms passed from animals to humans
Visceral larva migrans (VLM)
Which three zoonotic agents can cause OLM and VLM in humans?
- Toxocara canis
- Toxocara cati
- Baylisascaris spp. (B. procyonis - raccoons)
What is the biggest difference between Baylisascaris procyonis and Toxacara?
- Somatic migration in the raccoon (Baylisascaris) doesn’t occur (L enter mucosa then returns to GI as subadult)
How resistant are the Baylisascaris eggs?
- Requires hot water (65 C; 149 F, most hot tap water is 131)
- Bleach and most standard hospital disinfectants do nothing to kill the eggs
- Use boiling infectious for months to years
- Latrines of raccoons are part of the problem and the solution
- High concentration of eggs in an area (barn loft, attic space, tree)
What does the Baylisascaris larva do as they migrate?
- Larvae get bigger and bigger and bigger as they migrate
- 300um (L2 — 2mm in length) - we are also concerned with neural larval migrans
Often presents as acute eosinophilic meningoencephalitis
Neural larva migrans
Dirofilaria immitis, also known as _____________, is caused by D. immitis. D. immitis adult worms can cause pulmonary artery blockage in dogs, leading to an illness that can include cough, exhaustion upon exercise, fainting, coughing up blood, and severe weight loss.
heartworm
Cats and Dogs are good reservoirs for:
- Toxocara Canis, T. catis
- Ancylostoma spp., Uncinaria
The following is describing what agent?
Reservoir: Pigs, Rats, Bear
Transmissions: Ingestion of infected undercooked tissues
Dz in animals: None to Death
Dz in Humans: None to Death
Prevention: Don’t eat raw or undercooked food, good kitchen hygiene
Trichinella spiralis
The following describes the life cycle of:
1. L1 eaten, excyst, invade intestinal mucosa
2. Mature to adults in 2 days (M & F)
3. Day 5: viviparous F: birth to prelarvae
4. Prelarvae enter lymphatics and bloodstream
5. Invade striated muscle
6. Week 2-3, L1, roll up spiral, encysted
- ready to be eaten by next host
Trichinella spiralis
The following is describing what agent?
Reservoir: Rat (DH), Snail (IH)
Transmissions: Ingestion of L3 in snail or snail remnants
Dz in animals: Normal hosts-none
Dz in Humans: CNS - Eosinophils
Prevention: Avoid ingestion of L3 in snail or snail remnants (unwashed greens)
Angiostrongylus (Rat lungworm)
The following describes the life cycle of:
1. L3 eaten by a rat, L3 goes to the brain, molts to adult (1 cm) enters a vein, carried to heart, lungs, female releases eggs
2. Eggs hatch while in rat, L1 shed in rat feces
3. Mollusk eats L1, molts to L2, L3, in snail
4. Snail is eaten by rat or aberrant host
- Aberrant host: eosinophilic meningoencephalitis (A. cantonesis)
Angiostrongylus cantonensis
(T/F) We have Dracunculus medinensis in the USA
False, we have D. insignis
(T/F) Dracunculus insignis has more human cases compared to Dracunculus medinensis
False, no human cases for Dracunculus insignis
What agent causes the following?
Within a few hours of ingesting this parasite in infected fish:
- The worm burrows into the human intestinal wall resulting in an acute and transient infection with symptoms such as abdominal pain, vomiting, nausea, and/or diarrhea
Anisakis simplex
Is a cousin of fenbendazole, which is also known as Panacur. It is used to treat Baylisascaris and Anisakis
Albendazole
