Is the crust contagious?

After a few days, the fever blister bursts open and a highly infectious fluid is emptied. Afterwards the lip herpes heals with crust formation. Fresh crusts are still very contagious, as they contain a large number of viruses. The crusts dry up more and more and finally heal without scarring. In the later stage of the crust, the risk of infection decreases, but infection is potentially possible at any stage of the disease.

How long are fever blisters contagious?

Shortly before the fever blister becomes visible and in the first days after the outbreak, the risk of infection for other people is particularly high because the fluid in the blister contains live herpes simplex viruses. In general, however, a fever blister is contagious until it has healed completely – in other words, at any stage of the disease. The healing of cold sores usually takes seven to ten days.

Every person who has been infected with herpes once carries the pathogen inside them for a lifetime. This means that even if there is no acute outbreak with visible symptoms (fever blister), those affected still secrete viruses through the mucous membranes. In the case of a fever blister, however, the number of viruses excreted by the infected person is significantly higher than in the resting phases.

Treatment with creams containing an antiviral agent (e.g. Aciclovir) can inhibit the reproduction of the viruses and thus minimize the risk of infection. The treatment also accelerates the healing of the fever blister. The additional masking of the fever blister with a transparent herpes blister plaster also reduces the risk of infection.

When are fever blisters contagious?

Lip herpes is contagious even before the infection has fully broken out and a fever blister has formed. The first signs of a fever blister are an unpleasant itching and tingling at the affected area. Even at this stage, a large number of viruses are already present 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 infected with Herpes simplex viruses carry the pathogen inside them forever and also excrete viruses if they do not have a fever blister. However, in such phases, when the virus “sleeps” in the body, the risk of infection is much lower.