Epizootic catarrhal enteritis (ECE), nicknamed "green slime disease," is a highly contagious viral infection of the ferret gut famous for producing bright green, mucousy diarrhea. It is caused by a coronavirus and spreads rapidly between ferrets, often appearing soon after a new ferret is introduced to a household. While many otherwise healthy adult ferrets recover with good supportive care, the disease can be severe or life-threatening in older, weak, or already-sick ferrets, because the inflamed gut cannot absorb nutrients and the ferret becomes dangerously dehydrated and malnourished. Prompt veterinary care and aggressive hydration and feeding are the keys to recovery.
Last reviewed: June 2026
What ECE Is
ECE is an inflammatory disease of the small intestine caused by a ferret enteric coronavirus. The virus damages the cells lining the gut, blunting the structures that absorb nutrients, so food passes through poorly and the characteristic green, slimy diarrhea results. As described in Quesenberry & Carpenter's Ferrets, Rabbits, and Rodents, ECE is intensely contagious and classically erupts in a household one to several days after a new, often asymptomatic carrier ferret is added — which is how it earned a reputation as a disease of ferret shows and new arrivals. Older ferrets and those with other illnesses tend to suffer the most severe and prolonged disease, while young healthy ferrets may have milder signs.
The Signs to Watch For
The signature sign is bright green, mucous-laden diarrhea, but the full picture is broader. Affected ferrets often show sudden lethargy, loss of appetite, vomiting, and profuse diarrhea that may be green and slimy at first and later become grainy or seed-like (sometimes described as bird-seed stool) as the gut struggles to digest. Dehydration, weakness, and rapid weight loss follow if the ferret cannot keep up with fluid and nutrient losses. Because a ferret's gut transit is fast and its reserves are small, a ferret that stops eating and has profuse diarrhea can decline quickly. Any ferret with green mucousy diarrhea, especially after recent exposure to a new ferret, should be seen promptly (AEMV Pet Care Guides, 2024).
Why Dehydration Is the Real Danger
The virus itself is rarely directly fatal in a healthy ferret; the danger comes from the consequences of the damaged gut. Severe diarrhea and reduced eating lead to dehydration, electrolyte imbalances, low blood sugar, and progressive malnutrition, and these secondary effects are what threaten the ferret's life, particularly in older or debilitated animals. A ferret that becomes too weak to eat enters a downward spiral, since it needs nutrition to repair the very gut lining that is failing. This is why treatment centers on aggressive supportive care, and why owners should never simply wait out green diarrhea at home in a ferret that is lethargic or off food.
How Vets Treat ECE
There is no specific antiviral cure, so treatment is supportive and aimed at carrying the ferret through while its gut heals. Care includes fluid therapy to correct dehydration, anti-nausea medication, gastrointestinal protectants, and crucially, nutritional support with a highly digestible, palatable diet or syringe-fed recovery formula to keep calories going in. A complete, balanced, easily digestible diet supports gut healing and recovery (WSAVA Global Nutrition Guidelines, 2011). Antibiotics are sometimes used to control secondary bacterial overgrowth. Severely affected ferrets may need hospitalization for intravenous fluids and intensive feeding. Because the virus spreads so easily, sick ferrets should be isolated and strict hygiene practiced. Most healthy ferrets recover over one to two weeks with diligent care, though some shed virus and can infect others afterward.
When to See a Vet
Call your vet today if:
- Your ferret has bright green, mucousy, or grainy diarrhea
- Your ferret is eating less, lethargic, or has lost weight
- Diarrhea started after a new ferret joined the household
- There is intermittent vomiting along with loose stool
- One ferret is sick and you have others who may be exposed
Go to the ER immediately if:
- Your ferret is profoundly weak, limp, or unresponsive
- There is severe, watery diarrhea with obvious dehydration
- Your ferret has stopped eating and drinking entirely
- You see signs of low blood sugar such as staring, drooling, or collapse
- Vomiting is persistent and your ferret is rapidly declining
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Frequently Asked Questions
What does green slime disease look like in ferrets?
The hallmark is sudden bright green, mucousy diarrhea, often with lethargy, loss of appetite, and sometimes vomiting. As the disease progresses, the stool may turn grainy or seed-like (bird-seed stool) because the damaged gut cannot digest food properly. Dehydration and weight loss follow if losses are not replaced. The signs frequently begin a day or two after a new ferret is introduced, since the virus is highly contagious.
Is ferret ECE contagious to my other ferrets or pets?
It is extremely contagious between ferrets, spreading through contact with infected stool, and a new, healthy-looking carrier ferret often triggers an outbreak in a household. It does not infect dogs, cats, or people. Because recovered ferrets can keep shedding the virus, strict isolation of sick animals, careful hand-washing, and disinfection are important. Quarantining any new ferret before introductions is the best way to prevent an outbreak.
How much does it cost to treat a ferret with ECE?
An exotic vet exam runs $75 to $200, with fecal testing and bloodwork adding $80 to $250. Outpatient care with subcutaneous fluids, anti-nausea medication, and recovery diet often totals $150 to $500. A severely dehydrated ferret needing hospitalization with IV fluids and intensive feeding can run $500 to $1,500 per day. Exotic care carries a premium, but early supportive treatment greatly improves the odds and limits costs.
Can a ferret recover from ECE?
Yes, most otherwise healthy adult ferrets recover over one to two weeks with diligent supportive care focused on hydration and nutrition. The prognosis is more guarded for older ferrets and those with other illnesses, in whom the dehydration and malnutrition can become severe. The key to recovery is not waiting out green diarrhea at home but getting prompt veterinary support to keep the ferret hydrated and eating while its gut heals.
How do I prevent ECE when introducing a new ferret?
Because ECE so often arrives with a new, asymptomatic carrier, quarantine is the best prevention. House any new ferret separately for a couple of weeks, with separate food bowls, bedding, and litter, and wash your hands and change clothing between handling the new and resident ferrets. Watch the newcomer for any diarrhea or illness before introductions. Good hygiene and a gradual, monitored introduction greatly reduce the risk of an outbreak.
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