Hookworms Flashcards
What is the Super Family name for hookworms?
Ancylostomatoidea
What is the commone name for Ancylostoma Caninum?
Hookworm
What are the hosts of Ancylostoma Caninum?
Dogs and foxes. Paratenic hosts play a role.
Is Ancylostoma Caninum zoonotic?
Yes, occasionally uses human as final host however infections don’t reach full maturity.
What are the characteristic features of adult Ancylostoma Caninum?
Adults are smaller than ascarids, 1-2 cm. Have a characteristic hook appearance. Buccal capsule with 3 pairs of marginal teeth.
What are the characteristic features of the eggs of Ancylostoma Caninum?
Thin-shelled oval egg, 60-40 micrometers.
What parasitic species is this image showing?
Ancylostoma Caninum - buccal teeth present
What is this image showing?
Adult hookworm attached to the intestinal villi by buccal cavity.
How can you distinguish that these are hookworms?
The heads of both males and females are bent dorsally, giving them a “fishing hook” appearance
Is the life cycle of Ancylostoma Caninum direct or indirect?
Direct
What is the infective stage of Ancylostoma Caninum?
L3 outside of the egg
List the life cycle modes of infection of Ancylostoma Caninum?
- Percutaneous
- Per Os
- Paratenic hosts (rodents)
- Tranplacental
- Transmammary
What is the average PPP for Ancylostoma Caninum?
Approximately 14-21 days depending on mode of infection
Where is the site of infection for Ancylostoma Caninum?
Small intestine
What are the pathogenesis and lesions of Ancylostoma Caninum?
- Acute or chronic hemorrhagic anemia
- Pups infected by transmammary route challenged (low iron reserve)
- Moist eczema with percutaneous infection
What is this image showing below?
Small intestine hemorrhage caused by Ancylostoma Caninum infection
What are the clinical signs of Ancylostoma Caninum?
- Acute infections cause anemia and lassitude
- Severe anemia with diarrhea (blood and mucus)
- Chronic infections cause weight loss, poor hair coat, and loss of appetite
How is Ancylostoma Caninum diagnosed?
- Depends on clinical signs, history with hematological and fecal examinations
- Few hookworm eggs confirms infection only, not hookworm disease
- Eggs on fecal float
What are the treatments and preventatives for Ancylostoma Caninum?
- Remedies available for adults and larvae
- If disease is severe in young pups, iron may be required or blood transfusion.
- Treat weaned pups and adults every 3 months.
- Pregnant bitches should be dosed once during pregnancy and nursing litters twice at 1-2 weeks and again 2 weeks later
How can perinatal transfer of both Ancylostoma and Toxocara larvae be reduced?
Oral administration of fenbendazole, ivermectin, and selamectin
What are the hosts for Ancylostoma Tubaeforme?
Final host - Cats. Paratenic host - rodents.
Are the adult nematodes and eggs have similar characteristics in Ancylostoma Tubaeforme and Ancylostoma Caninum?
Yes, just infect different host species
What are the infective modes of transmission for Ancylostoma Tubaeforme?
Per Os, Percutaneous, Paratenic host. Transmammary and Transplacental does not exist in A. Tubaeforme.
What parasitic species do these eggs belong to?
Ancylostoma Tubaeforme - larvated and undeveloped egg
What is the common name for Ancylostoma Braziliense?
Hookworm
What are the hosts for Ancylostoma Braziliense?
Dogs and Cats final hosts. Paratenic hosts such as rodents play a role.
Is Ancylostoma Braziliense zoonotic?
Yes! Causes most severe cutaneous larval migrans in humans.
What are the life cycle for Ancylostoma Braziliense?
Per Os, Percutaneous, Paratenic host. Just like A. Tubaeforme, transmammary and transplacental aren’t a mode of infection.
What is the site of infection for A. Braziliense?
Small intestine
What are the pathogenesis and lesions of A. Barziliense?
They are less voracious blood suckers than A. Caninum hence less pathogenic.
What the hell caused this?
Cutaneous larval migrans
What are the clinical signs of A. Braziliense?
Mild digestive upset and occasional diarrhea
Does the larva that cause cutaneous larval migrans continue to develop into its adult stage in humans?
No, but skin lesions still persist
What are the hosts of Uncinaria Stenocephala?
Dogs, Cats, foxes are final hosts. Paratenic hosts play a role.
List the characteristic features of adult Uncinaria Stenocephala.
Small nematode, 1 cm, with 2 cutting plates on buccal capsule.
*Ignore the picture containing numerous adult nematodes* Which of these pictures is A. Caninum and which one is Uncinaria Stenocephala? How can you tell?
A. Caninum on the left and Uncinaria Stenocephala on the right because A. Caninum has 3 pairs of cutting teeth whereas U. Stenocephala has 2 cutting plates.
What are the modes of infection for the life cycle of Uncinaria Stenocephala?
Same as A. Caninum: Percutaneous (rare), Per Os (most common), Paratenic host, Transplacental, Transmammary.
What is the PPP for Uncinaria Stenocephala?
15-21 days
Where is the site of infection for U. Stenocephala?
Adults in small intestine
Is Uncinaria Stenocephala more or less voracious bloodsucker than A. Caninum?
Less voracious blood sucker
List the clinical signs of U. Stenocephala.
Anemia, Diarrhea, and interdigital dermatitis
How is Uncinaria Stenocephala diagnosed?
Eggs in fecal flotation, larval culture may be required when A. Caninum is endemic.
What are the treatment and preventative for U. Stenocephala?
Anthelmintic treatment and good hygiene.
What parasitic species does the egg circled belong to? What species does the smaller egg belong to?
Uncinaria Stenocephala - larger egg
Ancylostoma Caninum - smaller egg
