What is Wet Tail and what causes it?

There is a common misconception that Wet Tail (or proliferative ileitis) is simply diarrhoea. Whilst diarrhoea is certainly a symptom of Wet Tail they are not the same thing. Wet tail is an infection of the hamster's stomach and bowels caused by an overgrowth of bacteria.

The bowels in hamsters, like humans, normally contain bacteria which when of a certain type and in the right balance are good for the hamster, but if the balance of these "good bacteria" is upset or "bad" bacteria take over then severe consequences can result.

A number of bacteria have been implicated in causing Wet Tail including E. Coli and Campylobacter although, more recently it has been thought that it is mainly caused by a bacterium known as Lawsonia Intracellularis. Viruses and some parasites have also been suspected to be involved.

It is also thought that stress is a predisposing factor as it is more common when there is a major change in the hamster's life that it may find stressful, such as at weaning or when it has a change of home. Genetics are also believed to contribute as there is a higher incidence of Wet Tail in the offspring of hamsters that have suffered with and survived this illness. It is generally recommended that any hamster that has recovered from Wet Tail should not be used for breeding.

What types of hamster does Wet Tail affect?

There is some controversy over this, some authorities report that only Syrian hamsters are affected by Wet Tail while others think that it can affect all hamsters. Whichever is correct it is certainly true that it is seen much more often in Syrian hamsters and it occurs most commonly in young hamsters, shortly after weaning.

What are the symptoms of Wet Tail?

Severe diarrhoea usually very watery and with an offensive smell which causes the underside of the hamster to be wet including the tail. The affected hamsters will usually become lethargic, wasted and may make noises or vocalisations of distress while they still have the energy to do so. Wet Tail does have an incubation period of up to 7 days, which means it can be present but not showing signs yet, so if you get a new hamster it can make sense to keep it isolated or quarantined for 7 days to be sure that it is healthy. Once infected the hamster is affected the illness usually lasts 3 to 5 days.