Human papillomaviruses are viruses that infect skin and mucous membrane cells. Infection with HPV is usually asymptomatic and heals by itself within 6 to 12 months.
If HPV causes diseases, skin changes in the genital area, such as genital warts, are most common. Chronic infection with HPV over a period of years can lead to the development of precancerous lesions, which in the vast majority of cases resolve on their own. Rarely, higher-grade precancerous lesions may develop and require treatment. If these are not detected, cervical cancer can develop from them. Since a few years there is the HPV vaccination, which protects against infection with some HP viruses.
Frequency of HPV infection
Well over two-thirds of all men and women become infected with HPV at least once in their lives without realizing it. but the HP virus must not be confused with cervical cancer. Cervical cancer is caused by HPV, but this is only the virus that can lead to the formation of cancer-causing cells. An infection with HPV does not mean to develop cancer.
The number of new cases of cervical cancer has been steadily decreasing since 1990, which is probably also due to screening (PAP smear test). Every year, about 300 women in Austria develop cervical cancer, so the risk is rather low: the annual average is 9 out of 100.000 women.
Causes / symptoms / course of HPV infection
HP viruses are specialized on human skin and mucous membrane cells. They are transmitted through skin or mucous membrane contact. Humans have actually always lived with the HP virus. Therefore, the human immune system is adapted to the virus and can eliminate it in most cases without drug treatment. Almost always, an infection with HPV runs without symptoms. If symptoms do occur, they are usually harmless skin lesions, such as genital or genital warts (condylomas). Warts are harmless, but for most patients an unpleasant and stressful thing.
Genital warts are white, gray or flesh-colored and form in the genital area. They can occur on the vagina, labia, cervix, penis or anus. Usually the infection with genital warts is not very pronounced. They are often tiny and are detected only by chance during a gynecological examination. Sometimes, however, larger genital warts develop, which then itch or burn at the affected skin area.
If an HPV infection does not heal on its own, a chronic infection occurs, i.e. the viruses remain in the body permanently. A chronic infection with certain HP viruses can lead to the formation of precancerous lesions over the years, which can then develop into cervical cancer, for example, but also cancer of the labia, vagina, penis, anus, or mouth and throat.
Currently, there are about 120 known types of HPV. Some of them affect anal and genital tissues as well as the mouth and throat.
HP viruses can be divided into so-called low-risk and high-risk types.
- The low-risk types can lead to the formation of genital or genital warts or a minor cell change, a dysplasia, these are unpleasant but harmless. In 90 % of all cases, HPV types 6 and 11 are responsible.
- The high-risk types can lead to cervical cancer and all its precursors in individual cases. Most infections with high-risk types heal on their own. Cancer of the vulva, penis, anus or oral cavity can also be caused by HPV.
Transmission of these 4 types of viruses occurs mainly through sexual contact. However, sexual intercourse is not necessarily required for infection. Condoms only partially protect against HPV infection, their use is recommended, but not 100% protection.
Diagnosis of HPV infection
As part of cancer screening, a so-called PAP smear test is performed. A PAP smear cannot exclude an infection with HPV. It only determines whether precancerous lesions have formed.
A PAP smear is classified from PAP I to PAP V depending on the degree of cell alteration. If the results of a Pap smear are conspicuous, the cervix is examined by means of a colposcopy. If necessary, a biopsy is performed, i.e. a tissue sample is taken and examined under a microscope. An HPV DNA test can be used to determine whether a woman is infected with an HP virus from the high-risk group. Cells are extracted from the cervix with a small brush. These cells are then examined in the laboratory.
In Austria, it is not common practice to routinely perform an HPV DNA test, since an HPV infection alone has no disease value, as the vast majority of infections heal themselves. If you still want to be tested, you have to bear the costs yourself. This test is not recommended for deciding whether to vaccinate or not. If an HPV DNA test shows infection with one of the virus strains, it does not mean that cancer will develop. It only means that statistically the risk for it is higher.
Treatment of HPV infection
Normally, the human immune system is capable of fighting the virus on its own. An HPV infection usually runs without symptoms and therefore remains undetected. In a few cases, however, this is not successful and a permanent infection occurs. Over a longer period of time, they can develop into precancerous lesions. If these precancerous lesions are not detected and treated, it can lead to the development of cervical cancer after many years. It is therefore important to have a cancer smear (PAP smear) taken regularly by a gynecologist.
Genital warts caused by the HP virus usually disappear on their own, but can also be treated with special "bloodless" therapies be removed. If this is not possible, they are surgically removed.
Local therapy of genital warts with creams or ointments is usually done over a longer period of time. Some of these products must not be used during pregnancy. Skin irritation and swelling may occur in the treated area.
There are several options for medical treatment of genital warts:
- Dabbing the affected area of skin with a special acetic acidBurning and pain occur in the treated area. Treatment is given once a week over a long period of time. However, there is no scarring.
- Cold application with liquid nitrogen "icing": This treatment is done once or twice a week
- Laser surgical treatmentThis treatment is performed under local anesthesia and is the fastest way to remove genital warts.
Since 2006 there is also the possibility of vaccination against HPV. The HPV vaccination is a prophylactic vaccination, which means that it should prevent an infection with HPV. It does not, however, serve as therapy for infection with HPV, cervical cancer, or any other cancer caused by infection with HPV.
The vaccination against HPV consists of empty viral envelopes, which means that the vaccination cannot cause an infection with HPV. However, the vaccination is not effective against all HPV types, but only against 2 or 4 of the approximately 120 different types. There are currently 2 different vaccines on the market.
The quadruple vaccination protects against the high-risk types 16 and 18 and the low-risk types 6 and 11. This can prevent precancerous lesions as well as genital warts caused by these types of viruses.
The double vaccination protects only against the carcinogenic virus types 16 and 18. This vaccination can prevent precancerous lesions caused by these virus types, but genital warts can still break out.
At present, there is no information about the necessity of booster vaccination. Since the introduction of the vaccination in 2006, a decrease in the effect has not yet been determined, therefore it is still unclear when or whether a booster of the vaccination is necessary.
The Austrian Cancer Aid recommends
- Both girls and boys should be vaccinated before they start their first sexual activity, i.e. between the ages of 9 and 15 years old.
- Girls and women who are already sexually active may also benefit from the vaccination, specifically girls and women between 15 and 45 years of age.
- However, since boys and men can also be infected with HPV and can get HPV-caused cancers such as anal carcinomas, carcinomas of the pharynx and penile carcinomas and also transmit the infection, vaccination is also recommended for boys and men between 15 and 26 years of age.
Costs of the HPV vaccination
HPV vaccination has been identified as 13. Vaccination included in free school vaccination program. It is therefore free of charge for children under 10 years of age. The cost is covered by the federal and state governments.
What can the patient do against HPV infection?
If you have a fever, you should wait with the vaccination until the illness has subsided. Vaccination should not be given during pregnancy.
Even if you have been vaccinated against HPV, it is still important to have an annual cancer smear test (PAP smear test) as part of your preventive checkup with your gynecologist. HPV vaccination does not protect 100% against the onset of cervical cancer.