☉ Doctors online now - 15 minute priority booking available
- Cold sores are caused by the Herpes Simplex Virus Type 1, otherwise known as HSV1.
- HSV2 is a similar virus which usually causes genital herpes, but rarely can also cause cold sores around the mouth.
- Cold sores are spread by skin to skin contact, such as kissing someone who has an active cold sore.
- The first infection may not cause any symptoms, but may be triggered later.
- Cold sores can be triggered by stress, fatigue, viral illness, strong UV/sunlight exposure or during menstruation.