Cold sores are highly contagious and caused by the herpes simplex virus.

They can take around 10 - 14 days to heal but they can be uncomfortable or irritating throughout.

The herpes simplex virus can be caught when you have contact with people or things that carry the virus, for example sharing cutlery, towels or kissing someone who is infected.

Cold sores have some early symptoms such as itching, tingling or numb sensations. This is followed by a grouping of blisters which can be pus filled. These can then burst which makes them scab over. They can be painful and can also look unpleasant.