Fever blisters result from a herpes simplex virus which becomes active. This virus is latent (dormant) in afflicted people, but can be activated by conditions such as stress, fever, trauma, hormonal changes and exposure to sunlight. When blisters reappear, they tend to form in the same location.
Can fever blisters be spread?
Yes. The time from blister rupture until the sore is completely healed is the time of greatest risk for spread of infection. The virus can spread to your own eyes and genitalia, as well as to other people.
Treatment consists of coating the lesions ointment containing an antiviral agent, for example 5% acyclovir ointment. Presently, there is no cure, but there is much research activity underway in this field. Contact your doctor or dentist for the latest information.
Avoid mucous membrane contact when a lesion is present. Do not squeeze, pinch or pick at the blister. Wash hands carefully before touching your eyes or genital area, or another person. Despite all caution, it is important to remember that it is possible to transmit herpes virus even when no blisters are present.
CausesThe best available evidence suggests that canker sores result from an altered local immune response associated with stress, trauma or local irritants such as eating acidic foods (tomatoes, citrus fruits and some nuts).
Can canker sores be spread?No. Since they are not caused by bacteria or viral agents, they cannot be spread locally or to anyone else.
The treatment works to relieve discomfort and guard against infection. A topical corticosteroid preparation such as triamcinolone dental paste (Kenalog in Orabase O.1%®) is helpful. Unfortunately, no cure exists at present.