What causes oral thrush?

Oral thrush is a yeast infection caused by a fungus called Candida albicans. While around 1 in every 2 people live healthily with the fungus, at times it grows too quickly, causing a visible infection. If your child is on antibiotic treatment or taking inhaled corticosteroids (such as those in many commonly-used asthma puffers), they are more likely to have oral thrush. An immunocompromised child (a child with a weak immune system — either as a result of illness or a medical treatment), is also more likely to be infected.

What are the symptoms?

Oral thrush appears as milky, white patches on the insides of a child's cheeks, tongue or lips and cannot be wiped away easily, as the infection is under the skin. The patches might also appear red or inflamed. Usually, the infection doesn't cause irritation, however if the mouth area is very red and raw, it might be hard for your child to eat. Another sign that your child may have an oral thrush infection is drooling.

Thrush can also appear in the nappy area (nappy rash).

Is oral thrush contagious?

While the fungus is contagious, it doesn't transfer easily. The most common points of transfer include:

• teething toys
• dummies
• teats
• bottles

The yeast might transfer from one person to another, for example, when a child chews on an infected child's toy. Another common infection point for a baby is their mother's vagina (vaginal oral thrush) during birth, as the yeast often lives in small amounts in the vagina.

Treating oral thrush

Your doctor can prescribe your child antifungal drops or gel to help manage the infection. If you are a breastfeeding mother with an infected child, your doctor might also prescribe an antifungal gel for your nipples. This is because you might be spreading the infection to your child when feeding. You can continue to breastfeed as usual if your baby has oral thrush.

Preventing oral thrush

Maintaining a high level of oral (mouth) and personal hygiene is a good way to prevent the spread of the infection. If your child has teeth, this includes brushing twice a day and taking them to the dentist for check-ups and treatments. It is important to sterilise items that come into contact with your child's mouth, including teething toys, dummies, and bottles. Clean teats well in between feeds to ensure that your child doesn't become reinfected.

Does my child need to see a doctor?

If you think your child may have oral thrush, it's a good idea to take your child to see a doctor to get a diagnosis. Most cases are very mild, and will quickly clear up with prescription gel or drops.

Be sure to take your child to the doctor if:

• white patches appear in their mouth
• the rash keeps on coming back after treatment
• they have a fever or are feeling generally unwell
• you are concerned about your child’s health