Either of the two herpes viruses can bring on tongue herpes and its lesions:
Herpes Simplex Virus, Type 1 (HSV-1): Better known as oral herpes, it's also sometimes called cold sores or fever blisters.
Herpes Simplex Virus, Type 2 (HSV-2): Known as genital herpes, HSV-2 can also infect the tongue, particularly during oral sex.
Because herpes is highly contagious, you can easily spread it via open sores and saliva to other parts of your body –including your lips, cheeks, gums, the roof of your mouth, inside your nose, throat, chin, eyes, fingers, and elsewhere on your skin.
You also can infect others by kissing, sharing toothbrushes or eating utensils, being sexually intimate, or licking someone (something children are fond of doing.).