Encephalitozoon cuniculi in rabbits
Usually abreviated to E. cuniculi, this is a fairly common parasitic disease in pet rabbits. It is caused by a tiny protozoal parasite that can cause inflammation anywhere in the body, but often affects the brain or kidneys. The symptoms vary depending on the organs affected, but a common presentation is a head tilt and severe ataxia (a wobbly gait/loss of balance). Some affected bunnies are suddenly unable to stand because their balance is affected and some don't eat because this makes them feel nauseous (even though rabbits can't vomit).
Diagnosis is usually based on clinical signs although there is a blood test we can run to help us confirm it. Some studies show that 50% of all rabbits have antibodies to this parasite, even though most have never, and will never, show any sign of illness. This makes testing a little tricky and as the results take a while to come through, we usually start treating straight away.
An anti-parasitic drug called fenbendazole is given for 28 days to the affected bunny & all in-contact bunnies. This is in the form of a tasty paste or liquid, to make giving it easier.
Careful cleaning of the hutch and the use of water bottles and raised food and water bowls helps to avoid contamination with spores present in rabbit urine.
Although the infection is zoonotic, which means it can affect humans, it is unlikely to affect healthy people provided normal hygiene is practised. Those who are immunosuppressed should avoid contact with their urine.
Based on current expert advice, we do not suggest routine 9 day courses of treatment. We do however recommend 28 day courses if a new bunny is introduced.
For more information, the Rabbit Welfare Association has an excellent advice leaflet.