Cold sores and fever blisters are common, approximately 8 out of 10 people have the virus that causes them. Although it is difficult to avoid cold sores, learning more about them can help you prevent outbreaks and minimize the discomfort they produce.
The herpes simplex virus type 1 (HSV-1) causes cold sores and fever blisters. This virus spreads from person to person through skin contact or saliva, either directly or by sharing glasses or utensils. The majority of people are infected by the time they are 10 years old. The virus most often infects the area around the mouth, but it can also affect the skin on the fingers, eyes, and genitals, although genital herpes is usually caused by the herpes simplex virus type 2.
HSV-1 becomes inactive after the first infection and remains in the nerves of the face. Numerous things can trigger the virus to become active, resulting in an outbreak of cold sores. Triggers include colds and fevers, as well as mental and emotional stress, illness, trauma to the lips, dental treatment, poor nutrition, or sun exposure. Sometimes an outbreak is triggered for unknown reasons.
Signs and Symptoms
During the first infection with HSV-1, people may experience headache, fever, sores and swelling in the mouth, nausea, vomiting, and a sore throat. Symptoms begin to appear about a week after exposure and can last for 7 to 14 days.
Tingling, itching, or burning is the first sign of a new outbreak of cold sores. Swelling and redness follow, then small fever blisters appear. As the blisters pop, they form cold sores which eventually are covered by scab-like crusts. Cold sores usually take 8 to 10 days to heal.
Cold sores can usually be diagnosed by your physician or dentist through a series of questions about your medical history and an exam. Tests to diagnose cold sores are sometimes used for people who have other medical conditions.
Medicines, such as famciclovir (Famvir), valacyclovir (Valtrex), and acyclovir (Zovirax), are available that can help cold sores heal more quickly and reduce the pain and discomfort they cause. These medicines don’t treat the virus, but can minimize outbreaks. They must be taken as soon as you feel a cold sore forming; once the blisters appear, the drugs are not very helpful.
While you have fever blisters or cold sores, keep the area clean and use lip balm. Avoid touching the area or picking at the crusts that form. Also avoid kissing anyone or sharing items that touch the lips including cups, utensils, and towels.
Most of the time cold sores are not dangerous and quickly go away on their own. However, HSV-1 can cause illness in people with a weakened immune system. Contact your dentist or physician immediately if your sores last longer than a week or make it difficult to swallow or talk, cold sores occur with a fever, or you experience a second outbreak.
Children should not be kissed by anyone who has symptoms of an HSV-1 outbreak. There are vaccines being developed to protect people who have not yet been infected with the virus. However, most people are infected by the time they are adults.
Sunscreen on your lips may help prevent cold sores triggered by sun exposure, and taking medication when you expect to experience a trigger helps prevent an outbreak.
Once you have been infected with HSV-1, there is no way to get rid of the virus. However, with prompt treatment you can minimize the negative impact of cold sores and fever blisters.