Giardia

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This page quotes a published document. Everything below in quotation marks is copied word for word from https://capcvet.org/guidelines/giardia/, published by CAPC and retrieved on 2026-09-16. The quotations are excerpts; the document itself is linked and is the authority. Nothing has been reworded.

This page quotes the Companion Animal Parasite Council guideline for Giardia, section by section: the opening sentences of 7 sections, copied without change and linked to the guideline, which was retrieved on 2026-09-16. The guideline itself is the authority and carries the full text.

The guideline

Companion Animal Parasite Council, Giardia, at https://capcvet.org/guidelines/giardia/. Retrieved 2026-09-16. Each heading below is the guideline’s own, and the quotation under it is how that section begins. The full section, and the species tabs where the guideline gives them, are on the linked page.

Synopsis

CAPC Recommends Parasite testing should follow general guidelines. Treat all symptomatic dogs with recommended medication and protocol.

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Disease

Infections with Giardia are often asymptomatic, but if clinical signs are present they can include: diarrhea, which may be acute, intermittent, or chronic, and can be accompanied by flatulence, vomiting or mucous in the stool. In severe cases lethargy, inappetence, and weight loss may also occur.

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Prevalence

Giardia duodenalis infection is common in dogs. Regional differences in Giardia prevalence exist, but infections in dogs with clinical signs averaged 15.6% in dogs in the US.

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Diagnosis

Giardiasis is commonly misdiagnosed or underdiagnosed because of intermittent shedding and difficulty identifying cysts and trophozoites. Yeast may be mistaken for Giardia cysts due to their similar size and shape; however, yeast often show evidence of budding and do not have the internal structures seen in Giardia (i.e., median bodies, two to four nuclei).

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Treatment

Insufficient evidence is available for definitive recommendations in each clinical scenario; however, the majority opinion of the CAPC Board is that asymptomatic dogs may not require treatment. In healthy, non-symptomatic patients with a non-zoonotic Giardia assemblage, treatment may not be necessary.

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Control and Prevention

Concomitant with treatment, animals should be bathed with shampoo to remove fecal debris and associated cysts on the last day of treatment (Payne et al., 2002). Remove feces daily and dispose of fecal material with municipal waste.

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Public Health Considerations

Human infection from a dog or cat source has not been conclusively demonstrated in North America. However, people with increased susceptibility to infection due to underlying disease should consider limiting their exposure to Giardia -infected pets.

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Sources

  • capc-giardiaCAPC · retrieved 2026-09-16
    CAPC Recommends Parasite testing should follow general guidelines. Treat all symptomatic dogs with recommended medication and protocol. (Synopsis)

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