ABSTRACT Encephalitozoonosis is a significant microsporidial disease , often presenting in pet rabbits . This opportunistic parasite can spread to humans and many other animal species .
With rabbit pet ownership becoming increasingly common , veterinary nurses ( VNs ) should aim to educate owners on the husbandry , welfare and preventative care their pet rabbit needs .
The aim of this article is to discuss the life cycle of the parasite , the clinical signs of encephalitozoonosis and how VNs can aid encephalitozoonosis cases , from diagnosis through to long-term management .
Life cycle of E . cuniculi
E . cuniculi is a microsporidium belonging to the phylum Microspora [ 7 ] . It is an opportunistic intracellular parasite which can infect mammals , most commonly rabbits , but it also poses a zoonotic risk to immunosuppressed humans [ 8 – 10 ] .
Infection occurs through the ingestion of contaminated food or water , the inhalation of spores or by placental transmission [ 9 ] . One of the most common forms of transmission in pet rabbits is the ingestion of urinecontaminated food or water . This may occur when an infected rabbit is housed with or above a non-infected rabbit , and spores are shed into the urine ( Figure 1 ).
Keywords E . cuniculi , encephalitozoonosis , rabbit , awareness
Introduction
The Encephalitozoon cuniculi ( E . cuniculi ) parasite can cause renal and central nervous system disease in pet rabbits ( encephalitozoonosis ). Its seroprevalence is internationally recognised and it is suggested that up to 52 % of healthy pet rabbits in the UK have been exposed to the parasite [ 1 , 2 ] .
Rabbits are the third most popular pet in the UK , with an estimated pet rabbit population of close to one million [ 3 ] . Rabbits , among other non-traditional companion animals , are one of the most commonly rehomed and neglected animals .
The British Veterinary Association ( BVA ) highlighted that 78 % of UK veterinary surgeons believe the welfare needs of pet rabbits are not being met , reporting rabbits being housed inappropriately or alone , and in an inappropriate environment [ 4 ] . One of the biggest causes of poor husbandry is the lack of knowledge of the animal ' s needs [ 5 ] .
The PDSA found that only 25 % of pet rabbit owners used preventative flea / worming treatment and only 50 % of rabbits were receiving regular boosters [ 3 ] . An owner ' s obligations under the law in England and Wales are summarised in the Animal Welfare Act 2006 [ 6 ] .
As E . cuniculi poses a zoonotic risk , especially to immunosuppressed individuals , veterinary nurses ( VNs ) should aim to educate owners on common parasitic diseases and preventative rabbit care .
Learning outcomes
• Understand the aetiology of encephalitozoonosis
• Understand the management and treatment options for encephalitozoonosis
• Explore the role of VNs in the management of encephalitozoonosis
Figure 1 . Transmission can occur through the ingestion of urinecontaminated food or water when rabbits are housed together .
The spore is the infective form of the parasite and can survive up to 4 weeks in temperatures above 22 ° C . E . cuniculi may be more prevalent in the summer months but can present at any time [ 9 , 11 ] .
Following transmission , the parasite infects the macrophages and is carried to target organs such as the liver , kidney and brain . The host cell ruptures at the target organ and releases infective spores , resulting in granuloma formation and inflammation [ 12 ] .
Clinical signs
Rabbits may not always show clinical signs of infection , as latent infection is possible . Those suffering from encephalitozoonosis display various clinical signs , which are categorised into neurological signs , renal pathologies , ophthalmic conditions or a combination of these signs [ 12 ] .
The disease may be acute or chronic , and the clinical signs result from the granuloma formation , lesions and inflammation of the target organ ( s ).
Volume 38 ( 1 ) • February 2023
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