Cold sore is characterized as an annoying, small and painful red blister that usually shows up on or around the lips and mouth area and is usually caused by the herpes simplex virus-1 (HSV-1), which lives inside nerve tissue. Despite their name, cold sore has nothing to do with cold. Cold sore also commonly called as fever blister. Outbreaks are most regularly trigger by large amounts of stress.

Cold sore, as many viruses, is extremely contagious. The infection can be easily spread by skin to skin contact, as well as on personal items such as eating utensil, drinking cup, towel or anything the infected person has touched. It sometimes can also be triggered by exposure to the sun and can also be spread to other areas of the body.

Cold sore usually clears up without any treatment within a week to 10 days. Creams are available over-the-counter (OTC) to help relieve the symptoms of cold sore. Cold sore is most infectious when the blisters are newly formed, that is for the first 1 or 2 days of an outbreak. This is the best time to swab a cold sore if laboratory confirmation of the diagnosis is required.

It usually appears when you are sick or stressed. The virus lies latent (dormant) in the body and will become active when trigger by certain factors such as stress, sunburn, sickness, lack of sleep and etc.

It is most contagious when they burst but they remain contagious until they are fully healed. Ice helps in relieving the pain and restricts the herpes simplex virus from spreading. Ice treatment should be commenced when the itching begins.