Recurrent HSV-1 infections

Cold sores

Approximately 20-40% of HSV-1 seropositive individuals will experience a reactivation of the virus. A common and well known sign of HSV-1 reactivation is the cold sore. Most individuals who suffer from recurrent cold sores will be aware of it 1-2 days prior to eruption by a feeling of tingling, itching, pain, or swelling (the prodrome) at the usual cold sore site. The cold sore often occurs in the same location, such as the upper lip, lower lip, or occasionally inside the mouth, on the nose, chin, or cheek. Individuals may sometimes experience recurrences in more than one location.

The exact underlying molecular mechanisms for virus reactivation are unknown, but we know that stress, extreme sunlight (beach activities, skiing, tanning booths), fever, local skin trauma, and menstruation are some of the factors that may contribute to the eruption of cold sores. The blisters in a cold sore contain infectious virus but usually heal within a few days, with or without causing ulcers that crust over. Although cold sores are also called fever blisters they are rarely associated with fever or other systemic symptoms.

The skin

HSV-1 may reactivate in a finger as herpetic whitlow. Herpetic whitlow is often extremely painful, due to the presence of many sensory nerve endings and rigid skin in the finger tip.

The eye

HSV-1 may reactivate in the conjunctiva of the eye (keratoconjunctivitis, herpes dendriticum) and may occasionally involve both eyes. Frequent recurrences may lead to scarring, thickening of the cornea, and uveitis and is the leading cause of blindness in the developed world. In the immunocompromised person, the retina may be involved and cause sudden blindness.

Neurologic symptoms

Facial nerve paralysis (Bell's palsy) has been associated with HSV-1 reactivation. In rare instances, HSV-1 can also infect the brain (herpes encephalitis). This infection may be associated with headache and increasing confusion and, if left untreated, the patient may rapidly become unconscious and die. It is not known how and why herpes encephalitis occurs.

Some suggest that it represents reactivation of virus that is already latent in the brain; others suggest that it may spread from the nose or oral region through the olfactory nerve to the brain. Whatever the mechanisms, this condition requires early clinical recognition, laboratory testing, CT scans and prompt antiviral treatment.

Factors known to activate recurrent herpes infections

Internal (unpreventable) stress

• fever
• illness
• menstruation
• upset stomach or GI disturbance
• minor infections
• any disease that increases metabolism (e.g., diabetes, hyperthyroidism)
• presence of a second virus (e.g., common cold, flu)
• fatigue
• factors that depress the immune system

External (preventable) stress

• windburn
• ultraviolet radiation (sunshine, tanning booths)
• chilling
• excitement
• emotional stress
• drying of the lips
• allergic reactions, including reactions to food
• any physical injury
• dental treatment

Earliest Signs or Symptoms

• Up to 60% of cold sore sufferers experience classical cold sore outbreaks with pain, burning, itching, or tingling (prodromal stage) at the site where the blisters will form.
• This stage is usually short (less than 24 hours) and many people either don't experience these early symptoms or miss what they are. Some people will also feel fatigued for a couple of days before the outbreak. Many people find a blister present when waking up in the morning.

Treatment

• Cold sores should not be ignored.
• Most cold sores will clear up on their own after 7-10 days.
• Most treatments help reduce the discomfort and pain associated with cold sores as well helping it to heal faster. Some treatments may even help prevent cold sore blisters from forming.
• It is important to keep the cold sore moist to help with healing and to avoid further infection
• It is important to be extra vigilant with hygiene and avoid direct physical contact with others and avoid sharing towels, cups, cutlery, etc.