Gingivostomatitis must also be differentiated from herpangina , another disease that also commonly causes ulcers in the oral cavity of children, but is caused by the Coxsackie A virus rather than a herpes virus.  In herpangina, ulcers are usually isolated to the soft palate and anterior pillar of the mouth.  In herpetic gingivostomatitis, lesions can be found in these locations, but they are almost always accompanied by ulcerations on the gums, lips, tongue or buccal mucosa and/or by hyperemia, hypertrophy or hemorrhage of the gums. 
Oral herpes is a viral infection mainly of the mouth area and lips caused by a specific type of the herpes simplex virus. Oral herpes is also termed HSV-1, type 1 herpes simplex virus, or herpes labialis. The virus causes painful sores on the upper and lower lips, gums, tongue, roof of the mouth, inside the cheeks or nose, and sometimes on the face, chin, and neck. Infrequently, it may cause genital lesions. It also can cause symptoms such as swollen lymph nodes , fever , and muscle aches. People commonly refer to the infection as " cold sores ."
Antibodies that develop following an initial infection with a type of HSV prevents reinfection with the same virus type—a person with a history of orofacial infection caused by HSV-1 cannot contract herpes whitlow or a genital infection caused by HSV-1. [ citation needed ] In a monogamous couple, a seronegative female runs a greater than 30% per year risk of contracting an HSV infection from a seropositive male partner.  If an oral HSV-1 infection is contracted first, seroconversion will have occurred after 6 weeks to provide protective antibodies against a future genital HSV-1 infection. Herpes simplex is a double-stranded DNA virus .