Herpes labialis, commonly referred to as Cold sores, is an infection caused by herpes simplex virus (HSV). There are 2 types of the virus, type 1 (HSV1) and type 2 (HSV2). The first usually causes herpes labialis and the second genital herpes. However, overlapping is possible to be observed.
This is a fairly common infection that is very easily transmitted, resulting in nearly 100% of the population being infected by the age of 5.
The virus responsible for Cold sores is most commonly transmitted through direct skin contact or sexual contact with a person with active lesions. To a lesser extent, the transmission can occur by an asymptomatic carrier, i.e. by a person who does not present visible lesions. More rarely, it can be transmitted via indirect contact with contaminated objects, such as towels, razors, and other personal items.
The time that elapses between contact with the virus and onset of Herpes labialis’ symptoms is 4-5 days. Then, the lesions resolve but the virus migrates to the sensory ganglia of the neurons or to the lymphatic tissue and once the defense mechanisms of the body are impaired, it multiplies again leading to reactivation.
Usually, first contact with herpes virus at an early age is very mild. In this way the patient does not realize that he/she is infected. However, 20-30% of people infected at a young age, as well as older patients experience first contact with the virus in a more severe form, called Primary Herpetic Gingivostomatitis. Initially, there are precursor symptoms, such as fever, chills and bilateral regional lymphadenopathy. The clinical presentation includes erosion of the gums (desquamative gingivitis) and confluent, friable bullous lesions in the oral mucosa, causing difficulty in the consumption of food and drinks.
Before the occurrence of the Cold sores, tingling, stinging, burning or itching sensation may occur at the site at which herpes has inoculated. Then, one or more bullae containing a clear liquid are formed over an erythematosus red-base in the lip area. The bullae (blisters) break forming scab and healing occurs after 5‑6 days.
Stress, tiredness, possible injury, cold or flu, extreme weather conditions, pregnancy and menstruation are some of the factors that favor the recurrence of herpes labialis.
Treatment of herpes labialis generally consists of:
Herpes labialis or Oral Herpes’ treatment is not likely to lead to the eradication of the virus. Yet, in frequent recurrences (more than 6 episodes a year), prophylactic suppressive treatment with antiviral drugs is recommended, using, however, the lowest dosage for a long period of time (6-12 months).
Treatment should be administered within 48‑72 hours of onset of precursor symptoms in order to halt virus replication and reduce the severity of the episode.