Parasites part 1 Ana Salazar

Scientific name: Toxocara canis

Common name: Canine roundworm

Phylum: Nematoda

Identification: Round egg with thick, rough/pitted shell.

Zoonotic risk: Yes. Can cause visceral or ocular larva migrans in humans.

Diagnosis: Fecal flotation; identify roundworm eggs.

Transmission: Ingest embryonated eggs or infected paratenic hosts. Direct or indirect route.

Treatment: Pyrantel pamoate or fenbendazole.

Scientific name: Toxocara cati

Common name: Feline roundworm

Phylum: Nematoda

Identification: Round egg with thick, rough shell.

Zoonotic risk: Yes. Can cause larva migrans.

Diagnosis: Fecal flotation.

Transmission: Ingest eggs or infected prey.

Treatment: Pyrantel pamoate or fenbendazole.

• Scientific name: Baylisascaris procyonis

• Common name: Raccoon roundworm

• Phylum: Nematoda

• Identification: Round egg with thick, dark, rough shell.

• Zoonotic risk: Yes. Can cause severe neural or ocular larva migrans.

• Diagnosis: Fecal flotation.

• Transmission: Ingest eggs from raccoon feces or infected prey.

• Treatment: Veterinary-directed deworming.

• Scientific name: Ancylostoma caninum

• Common name: Dog hookworm

• Phylum: Nematoda

• Identification: Oval egg with thin shell and developing cells.

• Zoonotic risk: Yes. Can cause cutaneous larva migrans.

• Diagnosis: Fecal flotation.

• Transmission: Skin penetration, ingestion, or nursing. Direct life cycle.

• Treatment: Pyrantel, fenbendazole, or approved preventives.

• Scientific name: Uncinaria stenocephala

• Common name: Northern hookworm

• Phylum: Nematoda

• Identification: Oval, thin-shelled egg; approximately 25% larger than Ancylostoma.

• Zoonotic risk: Rarely; possible skin larva migration.

• Diagnosis: Fecal flotation.

• Transmission: Ingest larvae or skin penetration. Direct life cycle.

• Treatment: Veterinary-prescribed dewormer.

• Scientific name: Trichuris vulpis

• Common name: Canine whipworm

• Phylum: Nematoda

• Identification: Barrel-shaped egg with two bipolar plugs.

• Zoonotic risk: No established zoonotic infection.

• Diagnosis: Fecal flotation.

• Transmission: Ingest embryonated eggs. Direct life cycle.

• Treatment: Fenbendazole or approved preventives.

• Scientific name: Physaloptera spp.

• Common name: Stomach worm

• Phylum: Nematoda

• Identification: Oval egg with thick shell and developing larva.

• Zoonotic risk: No recognized common zoonotic infection.

• Diagnosis: Fecal flotation; eggs can be difficult to find.

• Transmission: Eating infected insects or paratenic hosts. Indirect life cycle.

• Treatment: Veterinary-directed deworming.

• Scientific name: Giardia duodenalis

• Common name: Giardia

• Phylum: Metamonada

• Identification: Oval cyst with internal nuclei; trophozoite has two nuclei.

• Zoonotic risk: Some strains infect humans and cause diarrhea.

• Diagnosis: Fecal antigen test, flotation, or direct smear.

• Transmission: Ingest cysts from contaminated water or feces. Direct life cycle.

• Treatment: Fenbendazole or veterinarian-directed medication.

• Scientific name: Tritrichomonas blagburni

• Common name: Feline intestinal trichomonad

• Phylum: Parabasalia

• Identification: Pear-shaped, motile organism with flagella.

• Zoonotic risk: No established zoonotic risk.

• Diagnosis: Fresh fecal smear or PCR.

• Transmission: Ingest trophozoites from contaminated feces. Direct life cycle.

• Treatment: Ronidazole under veterinary supervision.

• Scientific name: Cystoisospora spp.

• Common name: Coccidia

• Phylum: Apicomplexa

• Identification: Round or oval oocyst.

• Zoonotic risk: No; generally host-specific.

• Diagnosis: Fecal flotation.

• Transmission: Ingest sporulated oocysts. Direct life cycle.

• Treatment: Ponazuril or sulfadimethoxine.

• Scientific name: Toxoplasma gondii

• Common name: Toxoplasmosis parasite

• Phylum: Apicomplexa

• Identification: Very small, round oocyst.

• Zoonotic risk: Yes. Can cause flu-like illness and serious fetal disease.

• Diagnosis: Serology or PCR.

• Transmission: Undercooked meat or cat-shed oocysts. Indirect life cycle.

• Treatment: Clindamycin for affected cats.

• Scientific name: Cryptosporidium spp.

• Common name: Cryptosporidium

• Phylum: Apicomplexa

• Identification: Very tiny, round oocyst (4–6 µm).

• Zoonotic risk: Yes. Can cause watery diarrhea.

• Diagnosis: Acid-fast stain, antigen test, or PCR.

• Transmission: Ingest oocysts from contaminated water or feces. Direct life cycle.

• Treatment: Supportive care; depends on host and case.

• Scientific name: Dipylidium caninum

• Common name: Flea tapeworm

• Phylum: Platyhelminthes

• Class: Cestoda

• Identification: Multiple eggs grouped inside egg packets.

• Zoonotic risk: Yes. Humans can become infected by swallowing an infected flea.

• Diagnosis: Fecal examination or proglottid identification.

• Transmission: Swallow infected flea. Indirect life cycle.

• Treatment: Praziquantel and flea control.

• Scientific name: Taenia spp.

• Common name: Taenia tapeworm

• Phylum: Platyhelminthes

• Class: Cestoda

• Identification: Round egg with thick, radially striated shell.

• Zoonotic risk: Some species can infect humans.

• Diagnosis: Fecal examination or proglottid identification.

• Transmission: Eating infected prey or raw tissues. Indirect life cycle.

• Treatment: Praziquantel.

• CTVT page/section: ______

• Scientific name: Echinococcus spp.

• Common name: Hydatid tapeworm

• Phylum: Platyhelminthes

• Class: Cestoda

• Identification: Round egg with thick, radially striated shell.

• Zoonotic risk: Yes. Can cause hydatid disease.

• Diagnosis: Fecal testing/PCR; eggs resemble Taenia eggs.

• Transmission: Ingest infected organs or eggs. Indirect life cycle.

• Treatment: Praziquantel in definitive hosts.