Important Notice: Our web hosting provider recently started charging us for additional visits, which was unexpected. In response, we're seeking donations. Depending on the situation, we may explore different monetization options for our Community and Expert Contributors. It's crucial to provide more returns for their expertise and offer more Expert Validated Answers or AI Validated Answers. Learn more about our hosting issue here.
The traditional aphthous ulcer is not contagious. However – there are some infectious agents that can cause such ulcers – like HIV. Another common problem is that other infectious diseases, like herpes, can cause ulcerations in the mouth and they are thought to be aphthous but really they are something else. Those can be contagious.
