This is called latency. Herpes simplex virus 1 (HSV1) is the common cause of cold sores (oral herpes) around the mouth. Approximately 45 million people in the US have HSV infection about one in five people over the age of 12. Herpes simplex is a common viral infection that presents with localised blistering. Herpes simplex is caused by one of two types of herpes simplex virus (HSV), members of the Herpesvirales family of double-stranded DNA viruses. HSV may result in severe and widespread infection, known as eczema herpeticum. Herpes is a very common infection caused by a virus, called the herpes simplex virus, or HSV. HSV-1 is typically spread via infected saliva and initially causes acute herpetic gingivostomatitis in children and acute herpetic pharyngotonsillitis in adults. Along with ruptured vesicles in the tonsils and pharynx, an adult with newly acquired herpes type 1 can have fever, headache, fatigue, and sore throat.
Cold sores typically result from a viral infection called herpes simplex virus (HSV). Once reactivated, HSV travels down the nerve cells into the skin, causing its characteristic fever blisters typically in the same location.