What causes shingles? What is the contagious period for shingles? The virus causes painful sores on your lips, gums, tongue, roof of your mouth, and inside your cheeks. Because the virus is highly contagious, most people have been infected by at least 1 herpes subtype before adulthood. Varicella is less contagious when it resurfaces as shingles.
Shingles Symptoms, Causes, Treatment