Encephalitozoonosis (microsporidiosis) in Dogs
Encephalitozoonosis, also known as microsporidiosis, is a protozoal parasitic infection found in dogs, primarily caused by Encephalitozoon cuniculi (E. cuniculi). This parasite spreads within the body, leading to lesions in vital organs such as the lungs, heart, kidneys, and brain, significantly impairing normal bodily functions. While this condition is more commonly associated with affecting rabbit populations, it can also manifest in dogs.
The transmission of microsporidiosis typically occurs through the oronasal route, where animals come into contact with spore-infected urine, often by licking or sniffing. Dogs kept in kennels are at higher risk due to close contact with potentially infected animals. However, since microsporidia can survive in the environment for extended periods, virtually any outdoor dog is susceptible to infection.
Treatment for microsporidiosis in dogs remains largely experimental, with supportive therapy being the primary approach. Although many infected dogs recover fully without medical intervention, the disease can prove fatal, especially when contracted by puppies, either in utero or through nursing. Puppies may be stillborn or succumb to failure to thrive at a young age.
It’s crucial to note that this parasitic infection is zoonotic, meaning it can be transmitted to humans, particularly those with weakened immune systems. Therefore, thorough sanitization of the environment is essential. Using a 70 percent ethanol solution to clean up any contaminated urine and disinfecting the dog’s living area can help prevent the spread of the infection.
Symptoms and Types
Neonatal Infection (Manifests around three weeks of age)
- Growth retardation
- Dull coat, undersized body
- Inability to thrive
- Progression to kidney failure
- Neurological issues
Adults
- Brain irregularities
- Aggressive demeanor
- Seizure episodes
- Vision loss
- Progression to kidney failure
Causes
- E.cuniculi is present in spore-infected urine, typically transmitted through licking and sniffing behaviors.
Diagnosis
Your veterinarian will perform a comprehensive physical examination of your dog and gather a detailed medical history from you. It’s important to provide as much information as possible about your dog’s health and the symptoms observed leading up to the visit. In cases where your dog has recently given birth or if there are puppies undergoing treatment, they may appear notably small with a dull coat.
Due to the possibility of unusual aggression in some dogs, your veterinarian may also consider testing for rabies and distemper. In adult dogs, vision impairment ranging from limited to complete blindness, as well as occasional seizures, may be present. To assess the extent of organ involvement by the parasite, your veterinarian will order a chemical blood profile, a complete blood count, and a urinalysis. The presence of infectious spores can be identified in stained urine samples under a microscope.
Treatment
In numerous cases, dogs may fully recover independently if the infection hasn’t advanced to critical kidney or brain conditions. Supportive therapy, combined with a fungicidal medication, can aid in clearing the infection from the body. However, if severe brain or kidney disease is present, euthanasia may be necessary for the dog’s welfare.
Recovery and Management
It’s crucial to avoid contact with the urine of a dog afflicted with this disease. Consider keeping your dog under veterinary care until its urine is no longer contagious, if feasible. If your dog stays at home, ensure it’s confined to an enclosed area with a smooth, easy-to-clean surface. This setup facilitates the application of a 70 percent ethanol solution to eliminate spores in case of urine spillage. Utilize disposable floor coverings, blankets, or sheets to enhance cleanup procedures.
Individuals with compromised immune systems face the highest risk of contracting this disease from their pets. Ideally, these individuals should delegate pet care responsibilities to others until their pets are no longer contagious. Alternatively, if caring for their pets, they should take all necessary precautions, such as wearing face masks and disposable gloves, to safeguard themselves from potential exposure.