Are cold sores contagious when they are not visible?

Yes, cold sores are contagious even when they are not visible. The virus that causes cold sores, herpes simplex virus type 1 (HSV-1), can be spread through contact with the saliva or skin of an infected person, even if there are no visible sores. This means that you can spread the virus to someone else even if you don't have any symptoms yourself.

The risk of transmission is highest when the sores are visible, but it is still possible to spread the virus before and after the sores appear. This is why it is important to avoid kissing, sharing drinks, or coming into close contact with someone who has a cold sore, even if the sore is not visible.

If you have a cold sore, you should take steps to avoid spreading the virus to others. This includes:

* Avoiding contact with people who have a weakened immune system. People with weakened immune systems are more likely to develop severe complications from HSV-1 infection.

* Covering the sore with a bandage. This will help to prevent the virus from spreading to other people.

* Washing your hands frequently. This will help to remove the virus from your hands and prevent you from spreading it to others.

* Avoiding touching the sore. This will help to prevent the virus from spreading to other parts of your body.

If you have any questions about cold sores, you should talk to your doctor.