Thrush is a common fungal infection that affects the mouth and throat. It is caused by the Candida albicans fungus, which is normally present in the body in small amounts. However, when the immune system is weakened or the balance of bacteria in the mouth is disrupted, Candida can overgrow and cause infection.
Symptoms of thrush include white or yellow patches on the tongue, inner cheeks, or tonsils. These patches may be painful and can make it difficult to swallow. Thrush can also cause a burning sensation in the mouth and throat.