A case of squirrelpox has been confirmed in the village of Kirkbean on the Solway Coast, according to Saving Scotland’s Red Squirrels (SSRS).
A post-mortem examination was carried out on a dead red squirrel which was found in a garden at the end of October.
The results confirm that the rodent was infected with the highly contagious virus, which is often carried by grey squirrels but is deadly only to reds.
SSRS has urged local residents to remove garden feeders until the end of the month, and to be very vigilant for sick or dead red squirrels.
The first known squirrelpox outbreak in Scotland occurred in 2007 near Lockerbie and since then the disease has arisen in various red squirrel populations across the south of the country.
The first death of a red squirrel north of Scotland’s central belt was confirmed in Dunfermline last year following a post-mortem examination.
Two possible cases were reported near Stirling earlier this year.
Symptoms include ulcers, scabs and weeping lesions on the face, paws and genitalia, all of which can prevent reds from eating, drinking or moving.
It is usually fatal within two weeks and an outbreak can cause a substantial reduction in local populations of reds.
SSRS has reminded people to record any sightings of grey squirrels on their website.