Oral herpes (cold sores)
ICD codes: B00 What is the ICD Code?
With oral herpes (herpes labialis), painful blisters form, normally just on one side of the lips. For this reason, the condition is commonly referred to as “cold sores”. It is caused by infectious herpes viruses. Many people with oral herpes are repeatedly affected by it. Treatment is not usually required and the condition heals on its own within 1 to 2 weeks.
At a glance
- Oral herpes (cold sores) is caused by contagious herpes simplex viruses, especially type 1 (HSV-1).
- In Germany, an estimated 60 to 90 percent of people are carriers of this virus type.
- Once people have had oral herpes once, they often get it again repeatedly.
- It is particularly likely to break out when the immune system is weakened or strained – for example due to a cold or major physical exertion.
Note: The information in this article cannot and should not replace a medical consultation and must not be used for self-diagnosis or treatment.
What is oral herpes?
First of all the lip tingles or itches, then it swells, and finally small blisters form: many people with oral herpes recognize these symptoms. Oral herpes is admittedly a nuisance, but it usually clears up on its own after 1 to 2 weeks.
The condition is caused by contagious herpes simplex viruses (HSV). Many people are carriers of these viruses, but remain asymptomatic. However, people with oral herpes often get it repeatedly.
Oral herpes sufferers do not need to take sick leave. Students do not need to stay away from school.
What are the symptoms of oral herpes?
With oral herpes, painful blisters form, typically just on one side of the lips. However, the blisters can also spread to the surrounding skin, oral cavity or nose.
In such cases, the blisters can easily burst and weep when talking, laughing or chewing. Fluids such as juice or vinegar, and sour foods, can irritate the lesions that occur. Scabs form when they heal.
When oral herpes first occurs, it often causes more severe symptoms such as a high temperature, weakness or swollen lymph nodes in the neck area. This is because the body has not yet formed any antibodies against the virus that triggers the condition. This often happens during infancy.
The lining of the mouth (oral mucosa) can also become heavily inflamed the first time a person gets oral herpes. This inflammation is often painful and has a pungent smell.
What causes oral herpes?
Oral herpes is caused by an infection with herpes simplex viruses. There are two types of these, of which type 1 (HSV-1) is primarily responsible for oral herpes. Herpes simplex type 2 (HSV-2), on the other hand, triggers genital herpes.
The viruses are transmitted by the fluid in the blisters or swellings, for example through kissing or the shared use of objects. During oral sex, type 1 herpes viruses can enter the sexual partner’s intimate area and trigger genital herpes.
The herpes viruses establish themselves in the nodes (ganglia) of the facial nerve (trigeminal nerve). When the condition breaks out, they move along the nerve fibers in the lips and trigger the typical symptoms. Anyone who has once been infected with herpes viruses carries them throughout their life.
Oral herpes is particularly likely to occur when the immune system is weakened or strained, for example as a result of a cold or major physical exertion. Stress, hormonal fluctuations and skin irritation, for example by sunlight, are also possible triggers.
It is not completely clear why some people get oral herpes repeatedly and others do not.
How common is oral herpes?
In Germany, an estimated 60 to 90 percent of people are carriers of type 1 herpes simplex viruses (HSV-1) – the pathogens of oral herpes. The likelihood of infection increases with age.
Many people do not know that they have been infected, as they do not develop any symptoms. Medical practitioners believe that around 20 to 40 percent of people who have been infected with HSV-1 get oral herpes at some point.
How does oral herpes develop?
The lips of people with oral herpes often tingle or itch for hours or days before any blisters become visible. When the blisters heal they can form scabs. Like the blisters, these scabs crack easily and they can then bleed, too.
It takes around 1 to 2 weeks for oral herpes to heal. The blisters do not leave any visible scars when they are healed.
Some people suffer repeatedly from oral herpes. The condition usually occurs once or twice per year. However, in around 5 to 10 percent of people with oral herpes, it occurs more than 5 times per year. The symptoms often become milder over time.
In people who are otherwise healthy, oral herpes heals by itself and with no further consequences. In people with skin conditions such as neurodermatitis or severe burns, the herpes virus can settle in larger areas of the skin. But this rarely happens. A further rare occurrence is inflammation of the eyes, where herpes blisters develop on the eyelids, for example.
If the immune system is very weak – for example, due to chemotherapy – the lips can be inflamed more severely and for longer. In such cases, complications such as encephalitis can then occur.
How can oral herpes be prevented?
Certain irritants can activate herpes simplex viruses and increase the risk of an oral herpes outbreak. Possible triggers include:
- UV rays, for example from sunlight or a solarium
- common colds or high temperatures
- minor injuries and cracks to the lips
- physical or mental exertion
- taking anti-inflammatory cortisone products
- hormonal fluctuations, for example during the female menstrual cycle
Anyone wishing to reduce the risk of oral herpes can try to avoid these factors. It is also useful to try sun cream and good lip care products.
People who regularly suffer from oral herpes may also be able to take preventive medication. However, there has been little research into the effectiveness of these measures.
To protect themselves and others from infection, people with oral herpes should observe the following measures until they have completely recovered:
- not kiss anyone
- not share towels, crockery or cutlery with others
- wash their hands after touching their lips, for example after applying a cream
- avoid contact sports
- not engage in oral sex because this transmits the viruses to the mucous membranes of the partner’s sexual organs and can cause genital herpes
People with oral herpes can admittedly infect others even if they are not currently having an outbreak. However, this only happens rarely, so there is no need for them to take preventive measures unless they are not acutely ill.
Important: Babies up to eight weeks old are at particular risk because their immune system is not fully developed. As a result, people with oral herpes should not kiss the baby or put the baby’s pacifier into their own mouth. They should also wash their hands regularly and should not allow the baby to accidentally touch the herpes blisters.
More detailed information, for example on the prevention of oral herpes, can be found at gesundheitsinformation.de.
How is oral herpes diagnosed?
Oral herpes is easily identified from the typical symptoms. Anyone who has had oral herpes usually knows from the first indications when the condition is breaking out again. A doctor does not usually need to be consulted.
In rare cases, infections with type 1 herpes simplex viruses also occur on other skin areas. For diagnostic purposes the doctor can then take fluid (a swab) from the blisters and get it tested for herpes viruses in the lab.
How is oral herpes treated?
No treatment is normally required for oral herpes. The condition clears up by itself.
Anti-viral ointments, gels, creams and plasters can shorten the duration of an acute attack by around one day. To some extent they can also prevent blisters and scabs from forming. These medications contain the active ingredients aciclovir or penciclovir and they are available over the counter in pharmacies.
Correct use is important – for the medications to be effective, the treatment should be started within 24 hours of the first symptoms occurring. It is best to begin as early as possible. The medications are then applied to the affected skin areas every 2 to 3 hours for 5 days.
Unlike medications that are applied to the skin, tablets with anti-viral agents are only available on prescription. Tablets like these can also shorten the duration of the outbreak by around one day. It is not clear whether they are more effective than medications that are applied externally. However, tablets are easier to use, as they only need to be taken once or twice per day.
The protective effect of tablets is far greater for people whose immune system is weak, for example cancer patients during chemotherapy.
What is everyday life like with oral herpes?
People who occasionally suffer from oral herpes do not tend to be particularly restricted by it. They can still go about their work as usual and do not need to take sick leave. Children and adolescents can also continue to go to school.
However, the symptoms can sometimes be stressful. Being careful not to pass on the virus can also take some effort. Some people with oral herpes feel less attractive due to the visible blisters and may become withdrawn.
Tinted creams that combat herpes viruses can help conceal oral herpes slightly – at least in people with fair skin. People who wear make-up should remember that herpes viruses can spread easily via the fingers or used make-up products.
They should also consider that applying make-up over the oral herpes could impair the healing process – for example, if blisters and scabs tear when the make-up is applied or other pathogens enter the affected areas.
Special small plasters for herpes are available from pharmacies to protect the affected area of skin. Hygiene and a gentle touch are important when using these, as softened scabs could come away when removing the plaster, causing bleeding.
- Arain N, Paravastu SC, Arain MA. Effectiveness of topical corticosteroids in addition to antiviral therapy in the management of recurrent herpes labialis: a systematic review and meta-analysis. BMC Infect Dis. 2015 Feb 21;15:82. doi: 10.1186/s12879-015-0824-0. PMID: 25887308; PMCID: PMC4342818.
- Chen F, Xu H, Liu J et al. Efficacy and safety of nucleoside antiviral drugs for treatment of recurrent herpes labialis: a systematic review and meta-analysis. J Oral Pathol Med. 2017 Sep;46(8):561-568. doi: 10.1111/jop.12534. Epub 2017 Jan 25. PMID: 27935123.
- Chi CC, Wang SH, Delamere FM et al. Interventions for prevention of herpes simplex labialis (cold sores on the lips). Cochrane Database Syst Rev. 2015 Aug 7;2015(8):CD010095. doi: 10.1002/14651858.CD010095.pub2. PMID: 26252373; PMCID: PMC6461191.
- Glenny AM, Fernandez Mauleffinch LM, Pavitt S et al. Interventions for the prevention and treatment of herpes simplex virus in patients being treated for cancer. Cochrane Database Syst Rev. 2009 Jan 21;(1):CD006706. doi: 10.1002/14651858.CD006706.pub2. PMID: 19160295.
- Hull CM, Harmenberg J, Arlander E et al.; ME-609 Study Group. Early treatment of cold sores with topical ME-609 decreases the frequency of ulcerative lesions: a randomized, double-blind, placebo-controlled, patient-initiated clinical trial. J Am Acad Dermatol. 2011 Apr;64(4):696.e1-11. doi: 10.1016/j.jaad.2010.08.012. Epub 2010 Sep 20. PMID: 20851499.
- James C, Harfouche M, Welton NJ et al. Herpes simplex virus: global infection prevalence and incidence estimates, 2016. Bull World Health Organ. 2020 May 1;98(5):315-329. doi: 10.2471/BLT.19.237149. Epub 2020 Mar 25. PMID: 32514197; PMCID: PMC7265941.
- Korr G, Thamm M, Czogiel I et al. Decreasing seroprevalence of herpes simplex virus type 1 and type 2 in Germany leaves many people susceptible to genital infection: time to raise awareness and enhance control. BMC Infect Dis. 2017 Jul 6;17(1):471. doi: 10.1186/s12879-017-2527-1. PMID: 28683784; PMCID: PMC5500947.
- Pebody RG, Andrews N, Brown D et al. The seroepidemiology of herpes simplex virus type 1 and 2 in Europe. Sex Transm Infect. 2004 Jun;80(3):185-91. doi: 10.1136/sti.2003.005850. PMID: 15170000; PMCID: PMC1744847.
- Poole CL, James SH. Antiviral Therapies for Herpesviruses: Current Agents and New Directions. Clin Ther. 2018 Aug;40(8):1282-1298. doi: 10.1016/j.clinthera.2018.07.006. Epub 2018 Aug 10. PMID: 30104016; PMCID: PMC7728158.
- Usatine RP, Tinitigan R. Nongenital herpes simplex virus. Am Fam Physician. 2010 Nov 1;82(9):1075-82. PMID: 21121552.
- Whitley RJ, Roizman B. Herpes simplex virus infections. Lancet. 2001 May 12;357(9267):1513-8. doi: 10.1016/S0140-6736(00)04638-9. PMID: 11377626.
- Worrall G. Herpes labialis. BMJ Clin Evid. 2009 Sep 23;2009:1704. PMID: 21726482; PMCID: PMC2907798.
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