Even A-listers like Cheryl Cole aren't immune to cold sores.
Cheryl's cold sore first appeared on her appearance on Danish X Factor and persisted as she flew back to Heathrow airport.
Dr Rob Hicks explains: ‘Many things trigger attacks: colds and flu, menstrual periods, emotional upset, fatigue, bright sunlight and cold winds,' he commented on the BBC health website.
‘They're usually caused by herpes simplex virus type 1 (HSV-1) and caught through close contact with someone who has a cold sore.'
Luckily, Cheryl's not just a pretty face and knew she could cover it up with the help of a designer scarf.

Shop online for stylish scarves like Cheryl Cole's...
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