The most common symptom of oral herpes, caused by the herpes simplex virus, is cold sores.
Oral herpes can also cause fever and muscle aches.
Mouth sores most commonly occur in children aged 1-2 years, but they can affect people at any age and any time of the year.
People contract herpes by kissing or touching infected saliva, mucous membranes, or skin. Because the virus is highly contagious, most people have been infected before adulthood.
There are three stages to oral herpes after being infected:
- Primary infection: The virus enters your skin or mucous membrane and reproduces. During this stage, oral sores and other symptoms, such as fever, may develop. The virus may not cause any sores and symptoms. You may not even know that you have it. This is called asymptomatic infection. Asymptomatic infections occur twice as often as the disease with symptoms.
- Latency: From the infected site, the virus moves to a mass of nervous tissue in your spine called the dorsal root ganglion. There, the virus reproduces again and becomes inactive.
- Recurrence: When you experience certain emotional or physical stresses, the virus may reactivate and cause new sores and symptoms. One such stress may be a viral illness such as the common cold, hence the frequently used name of cold sores.
Oral herpes causes
Herpes simplex is a DNA virus that causes sores in and around your mouth. Two herpes subtypes may cause these sores.
- Herpes simplex virus type 1, or herpes-1, which causes around 80% of cases of oral herpes infections
- Herpes simplex virus type 2, or herpes-2, which causes the rest.
Oral herpes symptoms
Incubation period: For oral herpes, the amount of time between contact with the virus and the appearance of symptoms, called the incubation period, is around 2-12 days. The average is about four days.
Duration of illness: Signs and symptoms will last two to three weeks. In addition to below symptoms, fever, tiredness, muscle aches and irritability may occur.
- Pain, burning, tingling or itching occur at the infection site before the sores appear. Then clusters of blisters erupt. These blisters break down rapidly and, when seen, appear as tiny, shallow, grey ulcers on a red base. A few days later, they become crusted or scabbed and appear drier and more yellow.
- Oral sores: The most intense pain caused by these sores is felt when they first appear, and can make eating and drinking difficult. The sores may occur on the lips, the gums, the front of the tongue, the inside of the cheeks, the throat and the roof of the mouth. They may also extend down the chin and neck.
- The gums may become mildly swollen and red and may bleed.
- Neck lymph nodes often swell up and become painful.
- In people in their teens and 20s, herpes may cause a painful throat with shallow ulcers and a greyish coating on the tonsils.