Itchy, painful mouth blisters are unsightly and also highly contagious. Get tips on keeping junior safe from this viral infection.


Time and time again, you urge your child not to share their personal belongings such as towels and cutlery with their peers. It’s for a very good reason, too.

Apart from being a good hygiene habit to follow, the best way to prevent them from catching nasty viral infections is if refrain from sharing their belongings.

One viral infection is all it takes for junior to develop ugly sores on or around his lips and mouth. Mount Elizabeth Novena Hospital dermatologist Dr Eileen Tan explains that such sores are caused by the Herpes Simplex Virus (HSV). “There are two types of HSVs that can cause cold sores — HSV type 1 and 2. In general, cold sores are usually caused by HSV type 1.”

Your young ’un may complain of a tingling or burning sensation on and around his lips one to two days before the sore develops.

Associate Professor Catherine Hong, a senior consultant with the National University Hospital’s division of paediatric dentistry and university dental cluster, notes that her patients are usually infected with HSV in early childhood. “Young children — aged between 1 and 6 — may experience blisters, ulcers, painful inflammation of the gums and throat, fever and body aches when they’re infected for the very first time with HSV.”

“The reactivation of the Herpes simplex virus may be triggered by [exposure to] bright light, stress and fatigue.”

However, she adds that the majority of first-time infections can also occur without any noticeable symptoms. “Many will not even know that they have been infected.”

As your kiddo grows, different triggers can reactivate the HSV infection. Prof Hong says, “The reactivation of the Herpes simplex virus may be triggered by [exposure to] bright light, stress and fatigue.”

Prof Hong and Dr Tan answer your questions about HSV infection and cold sores…

Is it necessary for kids to see the doctor to treat their cold sores?

Dr Tan: If the cold sores are mild, it may not be necessary to see the doctor for each episode. Parents can try to cool the sores by gentle icing, pain relief with paracetamol or ibuprofen. Aloe vera gel — if your child isn’t allergic to it — may also provide some relief. Acyclovir cream is also useful for recurrent attacks. Antihistamines may be given by the doctor to reduce symptoms such as itchiness.

Prof Hong: Fortunately, symptoms such as fever, body aches, tiredness and mouth and throat pain due to ulcers and inflammation of the gums and throat will resolve spontaneously in 10 to 14 days for most children. The treatment for infections is largely based on symptoms. The doctor will typically prescribe medications for pain relief and advise you to ensure that your child is drinking enough water to remain hydrated. Sucking on ice chips or eating ice cream can also provide some pain relief. Doctors may also consider giving your child anti-viral medications if the infection is in the first two to three days. This can significantly decrease the duration and severity of the infection.

Can applying lip balm regularly prevent an infection?

Prof Hong: As cold sores on the lips may be triggered by exposure to sunlight, there is some evidence suggesting that applying lip balm with sunscreen prior to going out under the sun could reduce recurrent infections.

What are some of the most common ways a child may get infected with the virus?

Dr Tan: There are several possible routes of infection. Either via direct contact with an infected person or indirectly through contact with personal items like lip balm, razors and towels. Since HSV is contagious, it’s best to avoid direct contact with cold sores and avoid sharing these personal items.

How long does it usually take to recover from a cold sore?

Dr Tan: The sores usually last seven to 10 days. The virus may still be active and can be spread to others until the crust has resolved. Your body may develop antibodies after the initial infection.

What are the chances of a recurrence?

Dr Tan: In some studies, about 40 per cent of adults in the US get repeated cold sores. Cold sores are generally not serious. HSV infection may be life threatening for individuals with a low immune system or AIDS.

Prof Hong: While it is difficult to give a percentage with regard to recurrence rates as it varies greatly from person to person, the triggers for recurrence are quite predictable for each individual. For example, some individuals will get a cold sore when exposed to the sun for an extended period of time, while others only get it when they are highly stressed.

Associate Professor Catherine Hong is also an Assistant Dean (Education) at the NUS Faculty of Dentistry and a Senior Consultant in Paediatric Dentistry with the National University Centre for Oral Health, Singapore, which are part of the National University Health System.

Photo: iStock

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