HPV infection (human papilloma viruses)

Infections with the human papilloma virus (HPV) belong to the group of sexually transmitted viral diseases. Most HPV infections heal unnoticed, although in some cases harmless skin symptoms can occur, such as the formation of genital and anal warts.

More than 100 different subgroups of HPV are known. In about 40 species, an infection of the skin and mucous membrane cells in the genital area forms as a reaction. Some types are also suspected of being a cause of malignant diseases. It is now confirmed that some HP viruses are involved in the development of cervical cancer. However, it is still unclear how cells degenerate as a result of an HPV infection.

HPV infections are common in the population. It is estimated that 80 to 90 percent of sexually active women will become infected with an HPV virus during their lifetime. The frequency increases between the ages of 15 and 24. The majority of infected women no longer have the virus after one to two years. Men can also become infected with HP viruses. However, they usually do not notice the disease, since it runs completely unnoticed apart from minor skin changes on the penis.

HPV infection is caused by HP viruses, which belong to the family of non-enveloped DNA viruses. The genetic material of these viruses can exert an influence on the genetic material of the human cell in that special viral proteins stop the programmed cell death (apoptosis) of the infected host cell during reproduction. The human cell only perishes after the virus has multiplied, the virus particles are released and can infect new cells. This process does not cause a local inflammatory reaction, and no viruses are released into the blood (viremia). These are the reasons why an HPV infection is difficult to detect by the human immune system.

In total, there are more than 100 different HPV subspecies. Of these, 40 types can be transmitted through sexual contact and can trigger an HPV infection. HP viruses have the ability to penetrate the skin and mucous membranes, which is why transmission also occurs through direct contact with the skin and mucous membranes.

The different HP viruses cause different diseases. The majority of infections do not cause any symptoms and therefore usually remain undetected. HP viruses 6 and 12 cause genital warts (genital warts) in 90 percent of cases.

The so-called "high-risk group" of HP viruses includes viruses 16, 18, 31 and 45, as they are responsible for the development of cervical cancer.

In most cases, HPV infections make themselves felt through harmless skin symptoms. However, some virus subgroups can also be involved in malignant diseases (for example anal cancer, vaginal cancer, penile cancer, as well as head and neck cancer). So far, only the connection between certain HP viruses and cervical cancer has been confirmed.

HP viruses can cause diseases in various parts of the body:

Skin and mucous membranes:

In these areas, HPV infection can lead to the formation of warts.

Head and neck area:

HP- viruses can also cause wart formation here. Some virus subgroups can also be involved in the development of tumorous changes, for example on the vocal folds.

Genitalia:

So far, 40 subgroups are known that can lead to HPV infections in the genital area. They make themselves felt either by harmless wart structures (such as condylomas) or by cell degeneration.

90 percent of condylomas are caused by HP viruses 6 and 11. 20 to 30 percent of the diseases disappear by themselves. The main reason for this is the stability of the immune system.

HP viruses 16, 18, 31 and 45 belong to the "high-risk groups" that can trigger malignant cell degeneration. If the immune system is unable to eliminate these viruses, they can remain in the cell for months to years, causing it to undergo changes (dysplasia and neoplasia). These tissue changes can then develop into cervical cancer in the further course.

An HPV infection can usually be detected by skin changes. By means of a so-called acetic acid test, even very inconspicuous skin symptoms can be detected. To detect malignant (carcinogenic) changes, a tissue sample or a mucosal smear is taken.

Normally, the detection of the specific viral DNA is used for the diagnosis of HPV. This is usually done with the help of a polymerase chain reaction (PCR). With this method, even tiny amounts of virus can be detected.

There are various methods of treatment for HPV infections. On the one hand, a virustatic ointment can be applied, which inhibits the growth of viruses. This ointment can be applied by the affected person himself.

The doctor can also use highly concentrated trichloroacetic acid or laser therapy to combat the viruses. If the case is severe, surgery is usually performed. Since an HPV infection can occur again (recurrence), regular follow-up is very important.

A safe measure to protect yourself against HP viruses is the use of a condom. This is especially true if you frequently change sexual partners. However, this protective measure is not always sufficient, as the pathogens are highly infectious and very widespread. A 100 percent protection is therefore not given.

Since 2006, a vaccination called Gardasil® against the HP viruses 16, 18, 6 and 11 has been on the market in Germany.

Since March 2007, the Permanent Vaccination Commission (STIKO) at the Robert Koch Institute has issued a vaccination recommendation for vaccination against human papilloma viruses for all girls between the ages of 12 and 17. This vaccination includes three doses and should be completed before the first sexual intercourse. No information is yet known about the duration of vaccine protection or whether a booster is needed at a later date.

As the vaccination does not provide protection against all HP viruses, regular smear tests are essential for the early detection of possible HP infections and cervical cancer.