The symptoms to be aware of are easily spotted: the bird will be all fluffed up, moving lethargically, sitting still with its eyes closed, head tucked in and having difficulty when trying to eat. As there is little chance of recovery and the disease can be readily transmitted to other birds (but not to humans or animal pets).
Sadly, its kindest if such affected individuals are quickly and humanely dispatched and disposed of by authorised persons with appropriate knowledge and experience. It is also recommended that all feeders and birdbaths are thoroughly cleaned and taken out of use for a while.
The outbreaks are sparked by concentrations of birds feeding, bathing and drinking in the same small areas where faeces accumulate and contaminate. It is wise to avoid such build-ups by regularly changing the water in birdbaths, cleaning bird tables and feeders, and the ground below them, and varying their location.
Avoid food going mouldy – little and often is best. Nut and seed feeders should be protected from rain where possible – a plastic lid over the top helps - and should not be refilled until they are entirely empty in order to ensure a complete turnover of fresh contents.
Finally, please report any such incidents to www.gardenwildlifehealth.org