Wildlife charities have warned of potential cases of squirrelpox after receiving multiple reports of sick red squirrels in Dollar, Clackmannanshire.
The highly contagious virus is often carried by grey squirrels, but is deadly only to reds.
Symptoms include ulcers, scabs and weeping lesions on the face, paws and genitalia, all of which can prevent reds from eating, drinking or moving.
Post mortem results are the only way to confirm squirrelpox. It is usually fatal within two weeks.
Infected squirrels could appear quite lethargic, possibly remaining stationary for long periods of time and be easy to approach.
Experts at Saving Scotland’s Red Squirrels and the Eastern Lowlands Red Squirrel Group said it was “highly likely” the sick red squirrels had the disease, based on video evidence.
People have been urged to take down any wildlife feeders in their gardens  for the next two weeks and send any dead red squirrels found to the Royal (Dick) School of Veterinary Studies in Edinburgh.