How Long Are Cold Sores Contagious?

How long are cold sores contagious

Painful fluid-filled blisters most often found around the mouth and lips, cold sores are caused by the HSV-1 virus. They are very contagious and you should avoid all contact while you have them. But, how long are cold sores contagious? The answer to this question may surprise you, since we carry this virus for long after the cold sores are gone.

How Do Cold Sores Spread?

The herpes simplex virus is typically spread by direct contact such as kissing and oral sex, although it can also be spread by sharing glasses, utensils, and towels. Although cold sores are a classic symptom of herpes simplex, some people have the virus without experiencing any symptoms. The virus can be dormant in our bodies until something triggers it.

It can be reactivated by stress, fatigue, hormonal changes, fever, sun exposure, or surgery. The virus is still contagious even while dormant.

How Do You Avoid Spreading Them?

Here are some things you can do to prevent spreading the infection.

  • Avoid physical contact like kissing and oral sex;
  • Avoid touching the cold sore;
  • Don’t share personal items that have been near your mouth like cosmetics or utensils;
  • Be especially careful when coming into contact with people who have weakened immune systems like babies or people with immune system diseases.

How Long Are Cold Sores Contagious?

Unfortunately, once you contract the herpes simplex virus, you have it for life. Even if you don’t have a cold sore, you still carry the virus in your system and you can still pass it to other people. However, the virus is much more contagious if you have an active sore.


So, even though the virus is always contagious, avoid close contact with other people if you have an open sore.