Why am I at risk of oral thrush if I have HIV?

If you have HIV, you have a higher chance of developing oral thrush, because HIV weakens your immune system (the body’s natural defence system). This means you’re more likely to develop infections.

What is oral thrush?

Oral thrush, also known as oral candidiasis, is a yeast infection most commonly caused by a type of fungus called Candida albicans. Symptoms of oral thrush include:

  • sore white patches in the mouth that can be wiped off
  • a painful, burning sensation on the tongue
  • an unpleasant taste in the mouth that can be bitter or salty
  • redness and soreness on the inside of the mouth and throat
  • cracks at the corners of the mouth (angular cheilitis)
  • difficulty swallowing

Read more information about oral thrush in adults.

Thrush can also affect the vagina. You can read more information about vaginal thrush.

HIV and your immune system

HIV is an infection caused by the human immunodeficiency virus. HIV attacks the body's immune system by infecting CD4 cells, which are found in the blood and are responsible for fighting infection.

As the HIV infects more CD4 cells, the number of CD4 cells in your immune system starts to drop. This makes it harder for you to fight off infections, such as oral thrush.

If your CD4 count drops below 200, you will be at risk of catching many different infections. Infections that "take advantage" of an immune system weakened by HIV are known as opportunistic infections.

Opportunistic infections

Opportunistic infections include:

  • bacterial infections – such as pneumonia 
  • parasitical infections – such as toxoplasmosis  
  • viral infections – such as hepatitis 
  • fungal infections – such as thrush  

If you stick to your HIV therapy, the likelihood of developing an opportunistic infection remains low. However, repeated oral thrush infections could be a sign that your CD4 count has fallen.

Read more about treating HIV.

Getting help

If you have HIV, you should be under the care of an HIV clinic. If you get oral thrush, see your GP or visit your HIV clinic. If you have repeated episodes of oral thrush, tell the staff at your HIV clinic. For more information, see How will oral thrush be treated if I have HIV or AIDS?

Read the answers to more questions about infections.

Further information:

Page last reviewed: 03/12/2014

Next review due: 02/12/2016