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How long is cold sore contagious?


Cold sores, also known as fever blisters, are caused by the herpes simplex virus (HSV). This highly contagious virus can be transmitted from person to person through direct contact with an infected person’s saliva, such as kissing, sharing utensils or cups, and touching the cold sore.

The length of time that a cold sore is contagious varies depending on the stage of the sore. The first sign of a cold sore is usually a tingling or burning sensation on the lip, followed by the formation of a red blister that gradually turns into a cluster of fluid-filled blisters. During this stage, the cold sore is highly contagious, as the virus can easily spread through the fluid in the blisters.

After a few days, the blisters will burst and form a scab, which signals the end of the contagious phase. However, it is important to note that the scab often falls off on its own, and the healing process can take up to two weeks.

It is also important to mention that a person with a cold sore can still be contagious even without visible blisters. This is because the virus can still be present in the saliva or on the skin, and can easily be transmitted to other people.

To prevent the spread of cold sores, it is important to avoid close contact with infected individuals, and to refrain from sharing personal items such as utensils, towels, or lip balm. If you have a cold sore, it is recommended to avoid touching it, and to wash your hands frequently to prevent the spread of the virus. Over-the-counter creams such as Abreva can also help reduce the duration and severity of cold sores.

A cold sore is contagious from the first sign of a tingling or burning sensation until the scab falls off, which can take up to two weeks. It is important to take precautions to prevent the spread of the virus, and to avoid close contact with infected individuals.