Human papilloma virus (HPV) is the most common viral infection of genital tract.
general information
HPV is an extremely widespread virus group around the world. There are over 190 types of this virus, of which at least 13 lead to cancer development (they are known as high risk types). The human papilloma virus is transmitted mainly with sexual contacts, and most people are infected with them shortly after starting to lead sex. Two types of HPV (16 and 18) cause 70% of all cases of cervical cancer (RSHM) and pre -employed pathological states of the cervix.
The probability of getting sick
The human papilloma virus is transmitted mainly with sexual contacts, and most people are infected with them shortly after starting to lead sex. But penetrating sex is not required to transfer the virus. Genital belly contact is a well -established path of transmission of papillomavirus infection. HPV infection risk groups are children and adolescents from 15 to 18 years.
Cervical cancer develops as a result of acquired sexual means of infection with certain types of HPV. Risk factors for the development of RSM: the first sexual intercourse at an early age; Numerous sexual partners; Suppression of immunity (eg, people infected with HIV undergo an increased risk of HPV infection and are infected with a wider range of VPV types).
Symptoms and nature of the course of the disease
Most HPV infections do not lead to the onset of symptoms or diseases and passes themselves (about 90% pass within 2 years). However, a stable infection with certain types of HPV (most of the time with the types of 16 and 18) can lead to the development of pre -employed pathological conditions. Without treatment, these conditions can become cervical cancer. Today, cervical cancer is the most common disease associated with human papilloma virus. Cervical cancer is the fourth among the most common types of cancer in women, and the seventh in general: according to estimates, 528. 000 new cases worldwide were in 2012.
RSM symptoms usually appear only at the advanced stage of cancer and may include the following:
- Irregular, intermenstrual (between menstruation) or pathological vaginal bleeding after sex;
- Back pain, legs or pelvis;
- Fatigue, weight loss, loss of appetite;
- Unpleasant sensations in the vagina or discharge with an unpleasant odor;
- A swollen leg.
In later stages, the most serious symptoms may appear.
Papillomavirus infection is also involved in 20-90% of cases of flat cell cancer in the anus, oropharynx, vulva, vagina and penis. According to estimates, up to 90% of all cases of anal cancer are due to HPV-16 and HPV-18, and 40% of cases of vulva cancer, which is mainly found in elderly women, are associated with HPV-16.
HPV infection due to low -risk types cause year -in -law warts in men and women (pointed condiles or sexually transmitted warts). The average time between infection with the types of HPV-6 or 11 and the development of sexually transmitted warts is 11 to 12 months in men and 5-6 months in young women 16. Anogenital condiles are difficult to treat.
HPV-6 and HPV-11 can also cause a rare condition known as recurrent respiratory papillomatosis (RRP), in which warts are formed in the larynx or other parts of the respiratory tract. RRP is mainly observed in children under 5 years old (Youth PRP) or people in the third life of ten life (adult rrp). In rare cases, women with genital HPV infection can transmit the virus to the baby during delivery. An absurd RRP can lead to a serious problem due to the obstruction of the respiratory tract.
Complications after the disease
It was established that RSM in 100% of cases is due to oncogenic as the types of human papilloma viruses (HPV). In women with a normal immune system, cervical cancer develops in 15 to 20 years. In women with a weakened immune system, for example, with HIV infection in the absence of treatment, their development can only take 5 to 10 years. Despite limited data on Angeenital, cancer, different from cervical cancer, a growing number of real data indicates the relationship of human papillomavis with anus, vulva, vagina and penis. And while these cancers are less common than RSHM, their connection to HPV makes them potentially capable of preventing the use of the same primary prevention strategies as for cervical cancer.
HPV types that do not cause cancer (especially types 6 and 11) can cause pointed conditions and respiratory papillomatosis (a disease in which tumors grow in the respiratory tract that takes from nose and mouth to lungs). And while these conditions are very rarely leading to death, they can usually lead to a disease. Clear condiles are widespread and extremely infectious.
Mortality
There is a high global mortality of cervical cancer (52%), whose cause is human papillomavirus. In 2012, approximately 270. 000 women died of RSM, and more than 85% of these deaths occurred in countries with low and medium income.
Treatment
The screening of RSM is testing pre -financed conditions and cancer among women who have no symptoms and feel completely healthy. If screening reveals pre -finance pathological conditions, they can be easily treated and thus prevent cancer. Screening can also identify cancer at an early stage with a high probability of healing.
Given the fact that the pre -financed conditions have been developing for many years, all women aged 30 to 49 are recommended to go through screening at least once in their lifetime and more often. Screening is effective in reducing cervical cancer mortality only in the event of a significant number of women.
3 different types of screening are currently available:
- The usual test of Pap smear (PAP) and liquid cytology (LBC);
- Visual check using acetic acid;
- Test on high risk types of HPV.
In developed countries, there are programs that offer women screening opportunities, allowing you to identify most pre -employed conditions on stage when they can be easily treated. Early treatment of the human papilloma virus allows to avoid up to 80% of RSM development cases in these countries.
In developing countries, limited access to effective screening means that the disease is often detected only in later stages, when symptoms develop. In addition, the treatment of the disease in later stages is ineffective, which leads to high levels of mortality of RSM in these countries.
Effectiveness of vaccination
The results of clinical trials indicate that the two existing vaccines today are safe and very effective in preventing HPV 16 and 18 infection. Both vaccines are more effective if vaccination is performed before human papillomavirus is exposed. Therefore, it is preferable to perform vaccination before the first sexual contact. Vaccines do not treat HPV infection or HPV -associated disease (such as cancer).
In some countries, boys' vaccination against human papilloma virus is introduced, taking into account the fact that it allows it to prevent genital cancer in men and women, and one of the available vaccines also prevents the development of genital warts in men and women. In addition, vaccination of boys serves to prevent HPV circulation in the population of adolescents and young adults. Who recommends vaccination of girls from 9 to 13 years old, as this is the most effective, in terms of costs, a measure of public health against cervical cancer.
HPV vaccination does not replace screening in cervical cancer. In countries where VPV vaccine is promulgated, it may also be necessary to develop screening programs. By the end of 2013, the human papilloma virus vaccine was introduced in 55 countries from whom.
Modern Mathematical Models Show that at the Coverag of Girls 12-13 Years Old, the Full Course of Primary Immunization (3 doses) with a Vaccine Against Papillomavirus infection, it is possible to predict the risks of cervical developing cancer by 63%, cervicalIntraephylial Neoplasia of the Third Degree of Severity (Forerun) -By 51%, Cytological Disturbances in Age Cords to the Age Cords to Age. 30 years - 27%.
Vaccines
Currently, there are two vaccines that protect from 16 and 18 types of human papillomavirus, causing at least 70% of cervical cancer. These vaccines can also provide some cross protection against other less common types of HPV, causing RSM. One of these vaccines also protects from the types of HPV 6 and 11, which cause anogenital condylomas.
The development and registration of vaccines against papillomavirus infection determined the possibility of primary RSM prevention.
The last epidemics
Cervical cancer is the second most common type of cancer among women - according to estimates, 530. 000 new cases of disease are recorded annually, about 270. 000 patients are dying.
The incidence maintains the growth trend.
The probability of each woman's CRM disease on average during her life is 0, 53%.
Historical information and interesting facts
In the mid -seventies of the twentieth century, scientist Harold Tsur Hausen found that women suffering from cervical cancer are invariably infected with human papillomavirus. In 1983, he discovered papillomavirus DNA in a cervical cancer biopsy, and this event can be considered the opening of the VPH-16 oncogenic virus. In 2008, the Nobel Committee granted the Nobel Prize in the field of Harald Zur Hausen physiology and medicine for finding that the papilloma virus can cause cervical cancer.