Giardia antigen test
Stool ·Also called: giardia, giardia ELISA, giardia antigen, giardiasis test
What it is
Giardia is a single-celled intestinal parasite that causes soft, greasy, foul-smelling diarrhoea, most often in young animals and in dogs from kennels or shelters. The antigen test uses an immunological reaction, either in-clinic or at a laboratory.
Why your vet measures it
Giardia is a common and treatable cause of persistent diarrhoea that a routine worm check can easily miss. It is also frequently found in animals with no symptoms at all, which makes the result something to interpret alongside the clinical picture rather than treat automatically.
What a positive result can mean
- Active Giardia infection, particularly with soft or greasy diarrhoea
- Carriage without symptoms, which is common in kennelled and multi-pet households
- Persisting antigen for some weeks after successful treatment, so an early recheck can stay positive
What a negative result means
- A negative result makes Giardia unlikely, though shedding can be intermittent
Questions worth asking your vet
- My pet has no symptoms — does a positive result need treating?
- How long should I wait before rechecking after treatment?
- What hygiene steps reduce reinfection at home?
Related terms
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