1. What are oral ulcers in babies? Oral ulcers in babies, also called oral herpes, are a common oral disease in children. It usually presents as small ulcers on the oral mucosa, with redness and swelling around it, accompanied by mild fever, loss of appetite and other symptoms. This ulcer usually heals on its own within 1-2 weeks. 2. What are the causes of oral ulcers in babies? The main cause of oral ulcers in babies is infection with the herpes simplex virus (HSV). The virus can be spread through saliva, kissing, and sharing tableware. In addition, when the baby\’s immunity is weakened, he is also susceptible to infection