The human papillomavirus (HPV) is a pathogen that infects cells of the skin and mucous membranes. Over 100 different types of human papillomavirus are currently known.
Some types of the human papillomavirus lead to common skin warts on the feet, hands or face. Such warts occur in 5 to 20 percent of all children and in 3 to 5 percent of all adults.
Around 40 types of the human papillomavirus are sexually transmitted. These genital types of the HP virus are divided into low-risk and high-risk types.
Low-risk types cause the development of unpleasant but harmless genital warts(genital warts).
High-risk types can cause tissue changes
- in the mouth and throat area,
- in the pubic area,
- on the cervix,
- on the vagina,
- on the penis or
- on the anus
and lead to a malignant tumor disease. The most common form of cancer caused by the human papillomavirus is cervical cancer (cervical carcinoma).
Infection with the human papillomavirus occurs through direct contact with infected areas of skin. Infected cells are transmitted via microscopically small skin lesions.
Due to its resistance to drying out, smear infection via contaminated surfaces is also possible. This can happen, for example, through the shared use of towels for intimate areas.
It is extremely rare for the HP virus to be transmitted to the newborn during birth.
The genital types of the human papillomavirus are primarily transmitted through vaginal, anal and oral sex. An exchange of body fluids is not necessary for this.
In the course of their lives, around 70 percent of all sexually active people become infected with an HP virus. An accumulation occurs particularly between the ages of 15 and 24. The main risk factor for infection with the human papillomavirus is a frequent change of sexual partners.
The human papillomavirus can remain undetected in the body for years before symptoms appear. The time of infection may therefore be years in the past. If a person is infected with a genital HPV type, it is highly likely that this will also affect their partner.
In over 80 percent of cases, the infection is asymptomatic. It heals spontaneously after up to two years. In the majority of infected people, the immune system can successfully eliminate the virus. As a result, those affected usually do not know that they are or were carriers of the human papillomavirus.
A persistent infection with a high-risk type of the HP virus increases the risk of developing cervical cancer. Around 1 to 3 percent of all women who have been infected for a long time develop a tumor on the cervix. HP viruses of type 16 or 18 have been detected in 70 percent of cervical tumors.
In addition to a persistent infection with the human papillomavirus, factors such as
- a weakened immune system,
- chronic nicotine consumption,
- sexually acquired infections such as chlamydia,
- long-term use of contraceptive pills or
- a high number of births
the risk of cervical cancer is even greater.
Worldwide, 440,000 women are diagnosed with cervical cancer every year, particularly in third world countries. In Germany, the number of new cases is 5,500 per year and 1,500 women die from it. In women aged between 15 and 49, cervical cancer is the most common cancer after breast cancer. It accounts for 9 percent of all cancers.
Cervical cancer develops via various precursors, known as intraepithelial neoplasia. The term "intraepithelial" means that the cell changes occur exclusively on the epithelium, i.e. the uppermost layers of the skin.
If there is no treatment, the cell growths also penetrate into deeper layers of the skin. If they reach the blood and lymph channels, it is no longer a precancerous condition but a cancer. On average, it takes 10 to 15 years from infection with the human papillomavirus to the onset of cancer.
In the majority of cases, there are no symptoms of cervical cancer or its precancerous stages. However, possible indications are
- Irregular bleeding,
- bleeding during sexual intercourse or
- an unusual discharge.
As part of cancer screening, the gynecologist checks for precancerous lesions. If detected early, the development of cancer can be prevented in advance.
The HPV vaccination has been recommended for girls and women for several years. It prevents infection with HPV types 16 and 18, providing effective protection against cervical cancer.
With an incidence of 0.7 per 100,000 women and 0.4 per 100,000 men, anal carcinoma is a rare tumor. An infection with the human papillomavirus can be detected in 80 percent of all anal carcinomas.
A weak immune system and frequent changes in receptive anal intercourse are risk factors for anal cancer. Therefore, HIV-positive homosexual men and HIV-positive women who practice anal sex are significantly more frequently affected. These risk groups should therefore have an annual palpation examination of the rectum and anal swabs taken.
If preliminary stages of anal carcinoma are found during a screening examination, local treatment with Imiquimod follows. The cream is applied to the affected areas three times a week to induce a local inflammatory reaction.
This reduces the amount of human papilloma viruses in the long term and prevents the cell changes from progressing. Carcinoma cannot then develop.
Human papillomavirus 16 is the most common cause of anal cancer. The HPV vaccination for women covers this type. It is therefore assumed that early vaccination also prevents men from developing anal cancer. There is still a need for research in this area.
The most effective protection against infection with the human papillomavirus is sexual abstinence. Condoms do not always completely cover the infected areas of skin. They only reduce the risk of infection with the human papillomavirus. They do not offer complete protection.
Vaccination can protect against infection with the human papillomavirus. However, it is not suitable for treating existing infections or cell changes.
Gels, creams or foam suppositories do not offer protection against infection with the human papillomavirus.
Two vaccines are available in Germany to protect against infection with the human papillomavirus: Cervarix® and Gardasil®. Both protect against infection with human papillomaviruses 16 and 18.
Gardasil® also prevents infection with human papillomaviruses 6 and 11, which are responsible for the development of genital warts.
The Standing Vaccination Commission has recommended vaccination against the human papillomavirus for girls between the ages of 12 and 17 since March 2007. This vaccination recommendation was reviewed again in 2009 and found to be still valid. The statutory health insurance funds cover the costs of the vaccination.
Vaccination against the human papillomavirus is given in three doses for both vaccines. It should be completed before the first sexual intercourse.
According to studies, the effectiveness of both vaccines is 99 percent in non-infected women. Gardasil® protects against infection for at least eight years, Cervarix® for at least five years. In women already infected with the human papillomavirus, the effectiveness is significantly lower.
HPV vaccination provides effective protection against the later development of cervical cancer © Sherry Young | AdobeStock
The vaccines have not been shown to be effective against cell changes in the cervix.
Both Gardasil® and Cervarix® are considered to be well tolerated. Side effects include skin reactions at the injection site, tiredness or temporary increases in temperature.
In Germany, there is no public recommendation to vaccinateboys against the human papillomavirus. However, studies show that they also benefit from vaccination against the human papillomavirus.
Compared to unvaccinated boys, boys vaccinated against the human papillomavirus were found to have
- anal cancer and
- warts and
- and precancerous lesions in the perineum, penis and anus
significantly less frequently. Vaccination of boys is also seen as a sensible way of preventing infection of the female partner. This helps to contain the spread of the human papillomavirus.
The benefit of vaccination against the HP virus decreases significantly with the start of a sexually active life. However, after an individual risk-benefit assessment, vaccination against the human papillomavirus can also be useful here.
Vaccines containing so-called "virus-like particles" (VLPs) are available for HPV vaccination. They are developed from the viruses themselves and contain a very small virus component. This is the so-called main capsid protein L1, which, however, is not carcinogenic.
Two vaccines for HPV vaccination are currently licensed in Germany and available in pharmacies.
Gardasil ©: HPV vaccination with this vaccine is directed against HPV types 16 and 18 as well as types 6 and 11, the latter of which can cause genital warts. The vaccine therefore contains the VPLs of these four different HPV types. With Gardasil ©
- high-grade precursors of cervical cancer,
- cervical cancer itself,
- high-grade precursors of vulvar cancer as well as
- external genital warts
are prevented.
Cervarix ©: HPV vaccination with this vaccine prevents infection with HPV types 16 and 18. The vaccination is directed against the development of
- high-grade precursors of cervical cancer,
- cervical cancer itself, and
- high-grade precursors of vulvar cancer.
Cervarix© consists of the VPLs of HPV types 16 and 18.
The HPV vaccination with one of the two vaccines is given by intramuscular injection. It leads to an increased concentration of antibodies against the corresponding HPV types in the blood. The concentration is 100 to 1000 times higher after a vaccination than after a natural infection.
For the prevention of HPV infections of types 16 and 18, a completed basic immunization (3 doses) is considered safe. However, this only applies to girls and young women before their first sexual intercourse.
In some cases, sexually active women who have already been infected also benefit from an HPV vaccination. HPV vaccination can then prevent the recurrence of genital warts.
Newer vaccines combine different parts of HP viruses into one vaccine. These vaccines are more effective against low-risk and high-risk types than the previously used vaccines. They prevent genital warts and skin warts.
The vaccine must be tested in further studies and approved by the Federal Institute for Drugs and Medical Devices (BfArM). However, scientists are confident about the introduction of this new vaccine for HPV vaccination. It is already available as a basic vaccine in Gardasil and Cervarix and has a very good safety profile.
In addition, as a single vaccine it offers an economic advantage over the HPV vaccines already on the market.
The HPV vaccination effectively prevents HPV infection with types 16 and 18. This infection is the main cause of cervical cancer and its precursors. The vaccination therefore provides effective protection against the development of this type of cancer and is the best form of prevention. However, protection is only effective in young women and girls.
However, the vaccination rate in Germany is lower than in other countries where vaccination is also carried out.
A newer HPV vaccine could be a promising measure to prevent HPV infections. Unfortunately, the new HPV vaccine does not cover all HPV types during immunization. In addition to the high-risk types 16 and 18, there are others that also have this carcinogenic potency.
The HPV vaccination does not provide 100% protection. Vaccination failure and thus a lack of immunization is rare, but possible. For this reason, vaccinated women should also undergo cancer screening tests.
If the new HPV vaccination is established, people with a weak immune system will also benefit from the preventive effect against skin warts.
Health insurance companies may then also cover the costs of the HPV vaccination for boys. If both sexes are vaccinated with the HPV vaccine, an even greater reduction in cervical cancer is expected.
Other types of cancer that are also associated with HPV infections can also be reduced. These include penile carcinoma and carcinomas of the larynx.
