This is how contagious cold sores are
What are fever blisters?
Cold sores are painful small sores that typically form on the lip, mouth, or nose.
Cold sores are caused by an infection with the herpes simplex virus. It is a highly contagious disease that can easily be passed on to other people.
A fever blister is very contagious, especially in the first few days. After seven to ten days, the cold sore is usually healed and the risk of infection is over.
This is how contagious cold sores are
Cold sores are caused by the herpes simplex virus, which is extremely contagious. The virus is transmitted through a smear infection. The infection is easily transmitted, especially through direct contact (e.g. kissing) and sharing lip care products or glasses.
While cold sores are harmless to most people, they are quite painful and bothersome. For newborn babies, however, herpes simplex viruses can be very dangerous and painful.
Therefore, those affected should be aware of the very high risk of infection and keep the risk of passing the infection on to other people as low as possible.
By touching the fever blister, the viruses get to the hands and can easily be transmitted to other objects and people. Therefore, people should avoid touching the fever blister or wash their hands thoroughly afterwards.
It is best for patients to put a herpes patch over the cold sore and use an antiviral cream.
Read more on the subject under: Herpes Virus
What is contagious about the cold sore?
With a cold sore, a small blister forms that is filled with a liquid. The contents of the bladder as well as the fresh crusts contain live herpes simplex viruses and are therefore extremely contagious, with the freshly burst blisters being the main source of infection.
Infection with the herpes simplex virus type 1 (HSV-1) usually occurs at a young age and the level of infection in the population is very high.
However, the virus can only break out when the immune system is weakened by stress or a cold. In such cases, a fever blister forms that contains a large number of viruses.
Therefore, the risk of infection during an acute outbreak of cold sores is particularly high.
Read more on the subject under: Herpes Simplex Virus
Is the crust contagious?
After a few days, the fever blister bursts and a highly infectious fluid is emptied.
Then the cold sore heals with crust formation. Fresh crusts are still very contagious as they contain a large number of viruses.
The crusts dry out more and more and finally heal without scars.
In the later crust stage, the risk of infection decreases, but infection is potentially possible at any stage of the disease.
Read more on the subject under: Cold sores
How long are fever blisters contagious?
Shortly before the cold sore becomes visible and in the first few days after the outbreak, the risk of infection for other people is particularly high, as the liquid in the bladder contains live herpes simplex viruses.
In general, however, a fever blister is contagious until it has completely healed - i.e. at every stage of the disease. The cold sore usually takes seven to ten days to heal.
Every person who has become infected with herpes carries the pathogen for a lifetime. This means that those affected secrete viruses via the mucous membranes even if there is no acute outbreak with visible symptoms (fever blister).
With a fever blister, the number of viruses excreted by the infected person is significantly higher than in the resting phase.
Treatment with creams that contain an antiviral agent (e.g. acyclovir) can inhibit the multiplication of viruses and thus minimize the risk of infection. The treatment also speeds up the healing of the cold sore. The additional covering of the cold sore with a clear herpes blister plaster also reduces the risk of infection.
Read more on the subject under: Home remedies for herpes
When are fever blisters contagious?
Cold sores are contagious even before the infection has fully developed and a cold sore has formed.
The first signs of a fever blister are an uncomfortable itching and tingling sensation in the affected area. At this point in time there is already a large number of viruses here, which is why those affected should avoid touching their lips with their hands.
If it happens anyway, the patient must ensure adequate hygiene and wash their hands thoroughly. Otherwise, the viruses can easily be transmitted to other people through skin contact.
People who are infected with herpes simplex viruses carry the pathogen forever and also excrete viruses if they do not have a cold sore. However, in such phases, when the virus “sleeps” in the body, the risk of infection is significantly lower.
Read more on the subject under: Duration of cold sores
Can you get infected by kissing?
The herpes simplex viruses are transmitted through a smear infection with body contact.
Therefore, it is particularly easy to get infected with fever blisters by kissing. The viruses can also be transmitted to the partner during unprotected intercourse and lead to infection.
For these reasons, physical contact and the sharing of cutlery or glasses should be avoided for the entire duration of the fever blister.
Read more on the subject under: Herpes in the mouth
Are cold sores contagious if you've never had them?
More than 90% of people are infected with the herpes simplex virus. However, not every person who carries the virus has an acute outbreak of the disease. More than 80% of those infected do not develop cold sores, even when the virus is active.
If you've never had cold sores before, chances are you're one of the few percent of the population that doesn't have the virus. Nevertheless, these people can also get fever blisters. In any case, it is better not to take any chances and avoid direct skin contact with a person who has a cold sore.
