The most common strain of the virus that causes cold sores is herpes simplex virus 1. The herpes simplex virus in a cold sore is contagious. It can be spread to others by kissing, sharing cups or utensils, sharing washcloths or towels, or by touching the cold sore before it is healed. The virus can also be spread to others 24 to 48 hours before the cold sore appears.
Once a child is infected with the herpes simplex virus, the virus becomes inactive (dormant) for long periods of time. It can then become active at any time and cause cold sores. The cold sores usually don't last longer than 2 weeks. Hot sun, cold wind, illness, or a weak immune system can cause cold sores to occur.
Symptoms can occur a bit differently in each child. Some children don’t have symptoms with the first infection of herpes simplex virus. In other cases, a child may have severe flu-like symptoms and ulcers in and around the mouth. When cold sores come back after the first infection, symptoms are usually not as severe. The most common symptoms of cold sores include:
The symptoms of cold sores can be like other health conditions. Make sure your child sees his or her healthcare provider for a diagnosis.
The healthcare provider will ask about your child’s symptoms and health history. He or she will give your child a physical exam. A healthcare provider can usually diagnose your child by looking at the sores. Your child may also have tests, such as:
Treatment will depend on your child’s symptoms, age, and general health. It will also depend on how severe the condition is.
The herpes simplex virus infection that causes cold sores can’t be cured, but treatment may help ease some cold sore symptoms. Treatment may include antiviral medicine and other types of prescription medicines. These medicines work best if started as soon as possible after the first sign of a herpes infection or recurrence. Talk with your child’s healthcare providers about the risks, benefits, and possible side effects of all medicines.
In most children, cold sores don't cause serious illness. In some cases, the herpes simplex virus can cause inflammation of the brain (encephalitis). This is a serious illness and needs to be treated right away. It can lead to long-term problems of the brain.
Cold sores in a newborn baby can cause serious illness and death. This may be the case even when treated with medicine.
If someone in your household has herpes simplex, you can protect your child by making sure he or she is not exposed. Keep in mind that the virus may be in saliva even when there are no cold sores. Make sure your child doesn’t kiss, share cups or utensils, or share washcloths or towels with the person. Make sure your child doesn’t touch a cold sore.
If your child has a cold sore, make sure he or she does not:
The healthcare provider may advise keeping your child home from school during the first infection of herpes simplex virus.
Call the healthcare provider if your child has:
Tips to help you get the most from a visit to your child’s healthcare provider:
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