Tyzzer's Disease in Gerbils

What Is Tyzzer's Disease in Gerbils?

Tyzzer’s disease was first discovered in 1917 by Ernest Tyzzer. Dr. Tyzzer was a physician and the head of the Department of Comparative Pathology at Harvard University. He discovered the disease when his entire colony of Japanese Waltzing Mice suddenly died. Dr. Tyzzer analyzed post-mortem tissue samples and found lesions on the liver and intestines in these mice, as well as a spore forming bacteria known as clostridium piliforme (c. piliforme). The disease was named after Dr. Tyzzer and is found to most commonly occur in small rodents, especially gerbils.

Without treatment, Tyzzer's disease is usually fatal to a small rodent within a matter of days. Because of this high mortality rate, Tyzzer's disease is considered a medical emergency in gerbils. It is the most common fatal infectious disease in gerbils.

Symptoms of Tyzzer's Disease in Gerbils

•             Watery diarrhea

•             Staining around the anus or tail base

•             Depression/lethargy

•             Ruffled haircoat

•             Hunched posture

•             Loss of appetite

•             Dehydration

•             Weight loss/emaciation

Causes of Tyzzer's Disease in Gerbils

C. piliforme is a sporulating bacterium, which means the bacteria is enclosed in a protective casing. These types of sporulating bacteria can lie dormant for years, and gerbils can carry c. piliforme without showing signs of illness. It is transmitted to other gerbils by ingesting infected feces. Gerbils that are young, stressed, or pregnant are more susceptible to infection. Tyzzer's disease can be passed to other animals as well as people, although such occurrences are rare.

The origin of this bacteria is unknown, but has been found worldwide. As a sporulating bacteria, c. piliforme can survive at room temperature for over a year.

Tyzzer's disease is extremely contagious from one gerbil to another. Infection occurs when a gerbil ingests contaminated fecal matter, such as while eating food or grooming other gerbils. It is highly recommended to isolate any new gerbils for a minimum of one week to thirty days to observe for signs of illness before introducing to other gerbils. Overcrowding and unsanitary conditions (such as dirty bedding or food dishes) can lead to sporadic outbreaks.

How Veterinarians Diagnose Tyzzer's Disease in Gerbils

Diagnosing Tyzzer's disease in gerbils is challenging because the disease is often fatal before test results are available. Culture testing can be done on a stool sample to grow the bacteria and identify it, but results from this test can take up to a week or more. C. piliforme bacteria does not grow easily on standard culture material, so false negative or inconclusive test results are common.

New testing methods using genomic sequencing are being developed, but for now veterinarians are usually forced to diagnose Tyzzer's disease based on clinical symptoms. Fecal tests are usually performed to rule out intestinal parasites, and blood work can be ordered to look for internal organ damage.

Currently, the only way to definitively diagnose Tyzzer's disease in a gerbil is by performing a necropsy (assessment of the gerbil after it has passed). During a postmortem necropsy the veterinarian will examine the liver and intestines for lesions, and samples of affected tissue can be tested for the presence of c. piliforme.

Treatment of Tyzzer's Disease in Gerbils

Early treatment is crucial to a gerbil's survival if they are showing any signs of Tyzzer's disease. Even without a definitive diagnosis, veterinarians will treat symptomatic gerbils aggressively with fluid replacement therapy and antibiotics. Hospitalization is often recommended so the sick gerbil can receive injections of electrolyte replacement fluids several times a day. Antibiotics such as penicillin, tetracycline, doxycycline, or metronidazole will also be administered by injection or by mouth to combat the c. piliforme bacteria. In addition, probiotics and nutritional support are recommended.

If the sick gerbil was housed with other gerbils, treatment with oral antibiotics is often recommended for the other gerbils as well. This will hopefully prevent a deadly outbreak in the gerbil colony. Any gerbil showing signs of illness should be immediately isolated from other gerbils. The cage should then be thoroughly cleaned and disinfected.

How to Clean a Gerbil Cage

• Throw away all bedding and remaining food, and anything made of natural material such as wooden chew toys or nest boxes.

•  Wash the cage with warm soapy water, rinse, then spray with a 10% bleach solution. Let the bleach sit for at least 10 minutes, then rinse thoroughly to ensure no bleach residue remains before placing your gerbils back in the dry cage with fresh bedding.

• Soak water bottles, food, dishes, and remaining cage accessories in the bleach solution as well, then rinse thoroughly. It is worth noting that bleach can cause metal water bottles and exercise wheels to rust, so it may be best to replace these items. In addition, plastic is porous and can hold bleach even after rinsing, so these items may need to be replaced as well.

Recovery and Management of Tyzzer's Disease in Gerbils

Gerbils with Tyzzer's disease usually develop lesions in the intestines and the liver within 24 hours after ingesting infected feces. Symptoms of illness are most severe during the 5­–7 day window if the gerbil survives to that point. Some gerbils may recover from Tyzzer's Disease after 7–10 days of aggressive treatment. 

Prevention of Tyzzer’s Disease in Gerbils

Prevent re-occurrence and transmission to other pets by washing your hands before and after handling a sick gerbil. Proper sanitation is necessary to prevent spreading this deadly disease. Change your gerbil's bedding often and disinfect the cage and all accessories routinely. Ensure your gerbils have healthy immune systems by providing good nutrition, proper temperature, and housing them in a low stress environment. Always quarantine new gerbils for a minimum of one week and up to thirty days as advised by your veterinarian before introducing them to current pets in the household.