The fever blisters or cold sores that typically appear on the lips are manifestations of the herpes virus, which can also affect the skin elsewhere. Herpes is an extremely common viral infection and, although rarely serious, it causes major discomfort and is also anti-aesthetic. Even more bothersome is the fact that cold sores usually recur over a lifetime.
Herpes labialis is an infection caused by the herpes simplex virus, whose symptoms are observed mainly in the skin and the mucous membranes. It is usually acquired in childhood, so by adulthood most individuals have had contact with the virus. Cold sores on the lips are, in fact, just one of the manifestations (although the most common by far) of herpes simplex infection; the virus can also cause eye problems, affect the inside the mouth or the genitals and even cause more serious problems (meningitis).
A virus we have to live with
The infection rate of the population increases with age. It is estimated that most people over 35 are carriers of the virus. In fact, nearly 40% of the population have had an episode of herpes labialis in their life – although most infections go unnoticed because the symptoms are not evident.
The herpes simplex virus is transmitted by saliva or by direct contact with lesions anywhere on the body. Usually the infection goes entirely unnoticed. In other cases, after a few days several vesicles (small blisters) appear , which break to form ulcers that are usually painful. After a further few days a scab is formed and the lesion eventually heals.
Infections in children often occur within the mouth, with lesions that may be very painful and that prevent them from eating properly.
Once infection occurs, the immune system develops antibodies that prevent future infections. But the story does not end there. The virus never goes away, but remains dormant in the ganglion associated with the local nerve supply. From here it is reactivated periodically in the form of the typical cold sores.
The frequency of recurrent episodes varies greatly, although the average is once a year according to some studies. Outbreaks are often preceded by “warnings” in the form of a tingling or of pain, burning or itching 24 hours before the appearance of lesions, which usually last between 5 and 7 days.
The number and severity of outbreaks are partly determined by several triggers, including lowered defences, exposure to sunlight, fever, menstruation, the use of corticosteroids, emotional stress or trauma to the area (depilation, for example). The alternative popular name used for cold sores, “fever blisters”, points to the fact that the virus has traditionally been associated with febrile states when defences are lowered.
What treatments are there?
There is no definitive cure for herpes simplex. However, symptoms can be ameliorated, healing can be accelerated and recurrences can be reduced. Once an outbreak has been properly diagnosed, a number of general steps can be taken:
- Take great care with hygiene, frequently washing your hands (but especially after applying any treatment) so as to prevent transmission.
- Avoid kissing people susceptible to infection, especially children, if you have sores on your lips. Also avoid sharing crockery, cutlery, glasses, etc.
- Apply an antiseptic that will help dry out the lesion and prevent superinfection.
- Avoid oral sex.
As a general rule, to avoid outbreaks it is important to consider the factors already mentioned, and most especially, to avoid exposure to the sun by using appropriate sunscreens.
Although several antiviral drugs specific for herpes labialis are available, in most cases their use is not required, as the lesions are almost always mild (except in children).
Regarding antiviral creams, it has not been clearly demonstrated that they shorten the duration of the infection.