What is it?
Primary herpetic gingivostomatitis is the picture inside the mouth that appears when the herpes simplex virus is met for the first time. It is seen most often in children between six months and five years old; it can also develop in teenagers and adults who did not meet the virus in childhood. Not everyone who meets the virus develops this picture, and in the great majority the first encounter passes without any signs.
In the form that does cause signs, fever, irritability and loss of appetite come first. Within a day or two, many small blisters appear inside the mouth; these quickly break down into sores with a yellowish white base and red edges. The sores can be on the tongue, on the palate, inside the cheek and lip and at the entrance to the throat. The gums take on a bright red, swollen appearance and bleed when they are touched; bad breath and more dribbling go with it, and the glands under the jaw may become enlarged.
The mistake families often make is to put this picture down to teething. Teething can cause limited redness and irritability around the tooth that is coming through; it would not be expected to produce a high fever together with many sores spread through the mouth. The picture most often limits itself and heals within ten to fourteen days without leaving any marks. The real problem is not how long healing takes but the drop in fluid and food intake because of the pain during that time.
Signs
You will not necessarily have all of these at once.
Why does it happen?
- 01
The first encounter with the virus
The picture develops when the herpes simplex virus enters the body for the first time. After that first encounter the virus stays in a nerve ganglion and can come back in later years as a cold sore on the lip; the same widespread picture is not seen again.
- 02
Spread by contact and saliva
It is passed on by a kiss from someone with an active cold sore, through saliva and by shared dummies, bottles, glasses or toys. Spread from people who carry the virus without any signs has also been reported.
- 03
Group settings
Close contact and shared items are common in settings such as nurseries and playgroups. For that reason, rises can be seen from time to time in younger age groups, and it can appear in several children in the same setting within a short space of time.
- 04
Times when the immune system is weak
After another infection, or during treatment that suppresses the immune system, the picture can run a more severe course and healing can take longer. In that case, follow-up is carried out together with the doctor looking after the child.
How does it progress?
- 1
The warning stage
Fever, irritability, loss of appetite and discomfort on swallowing last a day or two. At this stage there may be no obvious sore inside the mouth yet, which is why another infection is suspected.
- 2
The blister and sore stage
Many small blisters appear inside the mouth and quickly break down into sores, and the gums are swollen and bleeding. This is the stage with the most pain and the least eating and drinking, and it lasts three to five days.
- 3
Settling down
No new sores appear, the edges of the existing ones begin to improve and the fever comes down. The child's general condition picks up noticeably and taking fluids becomes easier.
- 4
Healing and afterwards
The sores are expected to close within ten to fourteen days without leaving any marks. Because the virus stays in the body, it can come back later as a cold sore on the lip; this widespread picture, however, does not come back.
How is it treated?
In this picture the main aim of treatment is to ease the pain and to keep the child's fluid intake up. The dentist recognises the picture, tells it apart from things it can be confused with, such as teething and aphthous ulcers, and gives guidance on mouth care and feeding. The choice and the dose of anything for fever and pain is a decision for the doctor looking after your child; it is also worth remembering that aspirin should not be given to children.
The decision about an antiviral medicine also rests with the child's doctor. These medicines have been reported to be able to shorten the episode when they are started in the first days after the signs begin; they are not considered necessary in every child. Numbing gels applied inside the mouth are not advised for use in young children on your own judgement, because they can lead to difficulty swallowing and to problems with the dose.
Top of the list of what can be done at home is making fluids easier to take. Cool water, soft and cold foods and options such as plain yoghurt are most often easier to get down; acidic, salty, spicy and hard foods sting the sores. Tooth brushing is not given up altogether because of the pain but carried on gently with a soft brush. If the child is refusing fluids or is passing less urine, the situation should not go on being managed at home.
- If your child is refusing fluids, is passing less urine or has no tears when crying
- If they are much sleepier than usual and are hard to wake
- If a high fever lasts more than three days, or there is difficulty breathing
- If the sores have spread around the eye, or redness and discharge have started in the eye
How is it prevented?
- Adults with an active cold sore should not kiss babies and young children.
- Do not let children share things that go in the mouth, such as dummies, bottles, glasses and cutlery.
- While your child is ill, keeping them off nursery is best both for them and for the other children.
- Wash hands that have touched the sores; the virus being carried to an eye or a finger can cause problems of its own.
Frequently asked questions
- Could the sores in my child's mouth be from teething?
- Teething can cause irritability, more dribbling and limited redness over the tooth that is coming through. Many sores spread through the mouth together with a fever, and swollen bleeding gums, are not explained this way. When a picture like this is seen, the child needs to be examined and the distinction made by a clinician.
- Will their brother or sister, or we, catch it?
- Spread is possible. The virus is passed on in saliva and by direct contact; the risk lasts as long as the sores do. Avoiding shared items, hand hygiene and limiting kissing are advised during this time. People who have already met the virus do not get the same widespread picture, but a recurrence in the form of a cold sore on the lip can appear.
- Will this happen again?
- It would not be expected to be seen again in its widespread form, because this is the picture of the first encounter. Because the virus stays in a nerve ganglion, it can come back in later years as a cold sore at the edge of the lip. A cold sore is a more limited picture; it would not be expected to come with a fever, widespread mouth sores and bleeding gums.
This content is for general information and does not replace an in-person examination. Symptoms overlap between conditions, and a diagnosis can only be made clinically.