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."
Herpesviral encephalitis and herpesviral meningitis Herpes simplex encephalitis (HSE) is a rare life-threatening condition that is thought to be caused by the transmission of HSV-1 either from the nasal cavity to the brain's temporal lobe or from a peripheral site on the face, along the trigeminal nerve axon, to the brainstem. Despite its low incidence, HSE is the most common sporadic fatal encephalitis worldwide. HSV-2 is the most common cause of Mollaret's meningitis, a type of recurrent viral meningitis.
As with almost all sexually transmitted infections, women are more susceptible to acquiring genital HSV-2 than men. On an annual basis, without the use of antivirals or condoms, the transmission risk of HSV-2 from infected male to female is about 8–11%. This is believed to be due to the increased exposure of mucosal tissue to potential infection sites. Transmission risk from infected female to male is around 4–5% annually. Suppressive antiviral therapy reduces these risks by 50%. Antivirals also help prevent the development of symptomatic HSV in infection scenarios, meaning the infected partner will be seropositive but symptom-free by about 50%. Condom use also reduces the transmission risk significantly. Condom use is much more effective at preventing male-to-female transmission than vice versa. Previous HSV-1 infection may reduce the risk for acquisition of HSV-2 infection among women by a factor of three, although the one study that states this has a small sample size of 14 transmissions out of 214 couples.
The frequency and severity of recurrent outbreaks vary greatly between people. Some individuals' outbreaks can be quite debilitating, with large, painful lesions persisting for several weeks, while others experience only minor itching or burning for a few days. Some evidence indicates genetics play a role in the frequency of cold sore outbreaks. An area of human chromosome 21 that includes six genes has been linked to frequent oral herpes outbreaks. An immunity to the virus is built over time. Most infected individuals experience fewer outbreaks and outbreak symptoms often become less severe. After several years, some people become perpetually asymptomatic and no longer experience outbreaks, though they may still be contagious to others. Immunocompromised individuals may experience longer, more frequent, and more severe episodes. Antiviral medication has been proven to shorten the frequency and duration of outbreaks. Outbreaks may occur at the original site of the infection or in proximity to nerve endings that reach out from the infected ganglia. In the case of a genital infection, sores can appear at the original site of infection or near the base of the spine, the buttocks, or the back of the thighs. HSV-2-infected individuals are at higher risk for acquiring HIV when practicing unprotected sex with HIV-positive persons, in particular during an outbreak with active lesions.
Human herpes virus 1 (HHV1) is also known as herpes simplex virus 1 (HSV1). It is typically the cause of cold sores around the mouth. HHV1 can also lead to infection in the genital area causing genital herpes usually through oral-genital contact, such as during oral sex. HHV1 infections are contagious and are usually spread from skin-to-skin contact with an infected person through small breaks in the skin or mucous membrane. The HHV1 virus is more likely to be spread through things like sharing eating utensils, razors, and towels from a person who has an active lesion.
Avoid physical contact with anyone who has visible blisters and sores, and don't share towels or anything that may have come into contact with the sores. "It is also important that before you have any intimate contact with anyone you ask them about their sexual health, whether they have a herpes infection or have ever had any other sexually transmitted infection," Michael advises. "This is because statistically, people who have had an STI are more likely to be infected with the herpes virus. Using condoms and dental dams can also help reduce your risk of catching oral herpes."
HSV-1 and HSV-2 are transmitted by direct physical contact with a sore on an infected person. Facial or lip herpes is most often contracted by kissing someone with a cold sore. Genital herpes is most often contracted during sexual intercourse with a person who has an active genital sore. Genital herpes can also be contracted during or genital sex if a partner has labial herpes.
"When you are having an outbreak of oral herpes, symptoms usually start with a burning, itching or tingling sensation on your lips," Michael says. "This will intensify until a small rash, and then blisters, appear. These sores are commonly called 'cold sores'. The blisters are usually filled with a clear or slightly yellow liquid. Over a short time, these blisters will burst leaving a painful, raw area. These will then dry and scab over. The scabs will generally fall off after a week or two, leaving fresh clear skin beneath."