as you know i have no way of examining these mysterious red blisters over the internet so i am at a disadvantage. hand foot and mouth disease will give whitish papules (look like tiny blisters but are more firm) on the palms of the hands soles of the feet and canker-sore like lesions inside the mouth. what you are describing would not be consistent with hand foot and mouth disease.
my 4yr old daughter has red blisters arnd mouth neck ears hands chest and feet. is it hand mouth and foot disease? . she is having cold n cough but not fever.