What is cold sores?
Cold sores, commonly known as fever blisters, develop on the lips and mouth. This skin condition, caused mainly by the herpes simplex virus type 1 (HSV-1), causes a cluster of painful and contagious blisters. These blisters, which contain a clear fluid rich in virus, eventually form a scab. Although cold sores heal within a few days, they can be a source of discomfort due to their recurrent nature, unsightly appearance, and the pain they can cause.
Is a cold sore contagious?
Herpes simplex virus type 1 (HSV-1) is mainly transmitted through direct contact with the lesions (skin-to-skin) or through saliva. It can appear in or around the mouth (orofacial or labial herpes) and, in rare cases, cause genital herpes (which is mainly caused by herpes simplex type 2 or HSV-2).
Symptoms of cold sores
People with herpes usually develop mild symptoms. These are often more severe during the first episode of infection (outbreak) than during recurrences. The following signs are associated with it:
- a slight fever
- itching or tingling
- body aches
- sore throat
- headaches
- swollen lymph nodes
- a burning sensation on the edge of the lips, leaving a red area.
What causes cold sores?
HSV-1 is usually contracted in childhood, between 6 months and 4 years of age, after a primary infection (first contact with the virus), which is often asymptomatic. After this initial infection, the virus migrates to the sensory nerve ganglia where it remains dormant. Its reactivation can be caused by various factors such as fever, infection, trauma, emotional stress, sun exposure, or menstruation.
How can cold sores be treated in adults?
In healthy individuals, herpes infection is usually mild and resolves on its own. The effectiveness of acyclovir cream applied to the skin varies according to studies and generally appears to be less reliable than treatment with tablets. Frequent outbreaks warrant a medical consultation to assess the need for preventive treatment. Hand hygiene before and after each contact with lesions helps limit the spread of the virus. Also avoid scratching cold sore lesions and touching other parts of your face, including your eyes, as this could cause an eye infection (keratitis) or ocular herpes.
When should you contact a doctor?
Cold sores usually disappear within a few days. Contact a doctor if:
- You have frequent outbreaks.
- The rash on your lip spreads unusually or you have a high fever.
- You are immunocompromised or have severe skin rashes.
My baby has a cold sore. What should I do?
Transmission of herpes simplex virus type 1 (HSV-1) to infants can lead to serious complications, including damage to the central nervous system. Without a strong immune system, babies are particularly vulnerable to infections during the first few months of life. Symptoms to watch out for include:
- fever
- general malaise
- sudden appearance of blisters on the mucous membranes, eyes, and skin
- refusal to eat and/or drink
- redness on the mouth, lips, nose, eyes, or ears
- flu-like symptoms or dizziness
If your infant has a cold sore on their mouth or any other part of their body, consult your pediatrician immediately or contact the pediatric emergency department. Other conditions, such as eczema, can be confused with a primary herpes infection, which is why an accurate diagnosis is essential.
If you have a cold sore (herpes labialis), follow these simple rules to protect your child:
- avoid kissing your baby
- wash your hands before touching them
- do not share your cutlery or bath towels with your child
Are natural treatments such as essential oils effective?
While antiviral treatments have been proven effective against cold sores, this is not the case for natural remedies such as essential oils. Seek medical advice before using any alternative remedies.
Key points
Cold sores, also known as fever blisters, are not a serious condition, but they can be troublesome due to their tendency to recur, the pain they cause, and their unsightly appearance. Treatment at the first signs, combined with good hygiene measures, can speed up healing and limit the risk of transmitting the virus.
Reviewed under the supervision of Dr. Götti-Alipour