Cold sores, also known as fever ulcers, are infectious blisters that typically appear around the mouth or on the lip. They are generally caused by dry and cold weather conditions and are derived from the HSV-1 virus that is also associated with herpes. It is because of these associations that cold sores can feel like an embarrassing premise for some, despite their global commonality. In fact, in 2018, the World Health Organisation (WHO) noted that billions of people live with or have dealt with some form of HSV-1 in their lifetime. Some of the most common symptoms of cold sores include: Feelings of itchiness or burning Scabbing or leaking around the area Discolouration and redness Pain and sensations of stinging Outbreaks can last up to two weeks before fully deteriorating, though most tend to disappear on their own within 10 days of initial symptoms.