Pathogenesis (development of disease)
Herpes labialis is usually caused by herpes simplex virus type 1 (HSV-1). Less commonly (but increasingly), herpes labialis is also caused by herpes simplex virus type 2 (HSV-2), which for a long time was considered the exclusive causative agent of genital herpes.
The initial infection with HSV-1 occurs through saliva contact or smear infection. It is usually asymptomatic or undetected (gingivitis (inflammation of the gums), pharyngitis (inflammation of the throat)).
The typical time course of herpes labialis is as follows:
- Prodromal phase (preliminary phase): pain, burning, tingling, tightness with the skin still intact [this phase does not occur in all patients].
- Erythema phase: redness of the skin.
- Papule phase: appearance of painful papules (from Latin: papula “vesicle”).
- Vesicle phase: the papules become vesicles (fluid-filled vesicles). The secretion in the vesicles contains millions of viruses. It is highly infectious on contact.
- Ulceration phase: bursting and fusion of the vesicles. Painful, weeping wounds are formed.
- Crusting phase: formation of very itchy crusts and scabs.
- Healing phase: healing of the remaining redness and swelling without scarring.
Approximately 30% of adults have recurrent symptoms.
The following factors can trigger herpes labialis:
Etiology (causes)
Behavioral causes
- Emotional stress, psychological stress
Disease-related causes
Blood, blood-forming organs – immune system (D50-D90).
- Immunodeficiency, unspecified
Infectious and parasitic diseases (A00-B99).
- Febrile infectious diseases
Pregnancy, childbirth and puerperium (O00-O99).
- Pregnancy
Injuries, poisonings and other consequences of external causes (S00-T98).
- Injuries, unspecified
Other causes
- Premenstrual and menstrual (before/during menstruation).
- Herpes solaris due to sun exposure
