Human papillomavirus (HPV) is the most common viral infection of the genital tract.
General information
HPV is a group of viruses extremely widespread worldwide. There are more than 190 species of this virus, of which at least 13 lead to the development of cancer (they are known as types of high risk). The human papilloma virus is transmitted mainly with sexual intercourse and most people are infected with them shortly after they start having sex. Two types of HPV (16 and 18) cause 70% of all cases of cervical cancer (RSHM) and precancerous pathological conditions of the cervix.
The likelihood of getting sick
The human papilloma virus is transmitted mainly with sexual intercourse and most people are infected with them shortly after they start having sex. But no penetrating sex is required to transfer the virus. The contact for the genitals of the abdomen is a well -established path of transmission of papillomavirus infection. The risk groups of HPV infection are children and adolescents aged 15-18.
Cervical cancer develops as a result of acquired sexual agents for infection with certain types of HPV. Risk factors for the development of RSM: the first sexual contact at an early age; Numerous sexual partners; Immunity suppression (for example, HIV-infected people undergo an increased risk of HPV infection and are infected with a wider spectrum of VPV species).
Symptoms and nature of the course of the disease
Most HPV infections do not lead to symptoms or diseases and pass (about 90% pass within 2 years). However, a stable infection with certain types of HPV (most often with types of 16 and 18) can lead to the development of precancerous pathological conditions. Without treatment, these conditions can develop in cervical cancer. Today, cervical cancer is the most common disease associated with human papillomavirus. Cervical cancer is the fourth among the most common types of cancer in women, and the seventh as a whole: according to estimates, 528, 000 new cases in the world were in 2012.
RSM symptoms usually only occur in the advanced stage of cancer and may include the following:
- Uneven, interb (between menstruation) or pathological vaginal bleeding after intercourse;
- Back pain, legs or pelvis;
- Fatigue, weight loss, loss of appetite;
- Unpleasant sensations in the vagina or disposal with an unpleasant odor;
- One swollen leg.
In the short stages, more severe symptoms may occur.
Papillomavirus infection also participates in 20-90% of cases of cancer of the plain cells of 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 found mainly in elderly women, are associated with HPV-16.
HPV infection due to types of low risk causes anogent warts in men and women (pointed warts or warts transmitted sexually). The average time between HPV-6 or 11 infection and the development of sexually transmitted warts is 11-12 months in men and 5-6 months in young women 16. Anogenital warts are difficult to treat.
HPV-6 and HPV-11 can also cause a rare condition known as recurrent respiratory papillomatosis (RRP), whereby warts are formed in the larynx or other parts of the respiratory tract. RRP is observed mainly in children under 5 years of age (minor PRP) or in people of the third ten life (RRP for adults). In rare cases, women with genital HPV infection can transmit the baby's virus at birth. Absurd RRP can lead to a serious problem due to obstruction of the respiratory tract.
Complications after the disease
RSM has been found in 100% of cases due to oncogenic as types of human papillomavirus (HPV). In women with a normal immune system, cervical cancer develops in 15-20 years. In women with weakened immune system, for example, with HIV infection in the absence of treatment, its development can only take 5-10 years. Despite the limited data on the angian, cancer other than cervical cancer, the increasing number of actual data shows the connection of the human papillomavis with anus, vulva, vagina and penis. And although these cancers are more commonly found than RSHM, their relationship with HPV makes them potentially capable of preventing the use of the same primary prevention strategies as in cervical cancer.
HPV species that do not cause cancer (especially types 6 and 11) can cause pointed warts and respiratory papillomatosis (a disease in which tumors grow in the respiratory tract leading from the nose and mouth to the lungs). And although these conditions very rarely lead to death, they can often lead to illness. Acute warts are widespread and extremely infectious.
Mortality
There is a high global mortality from cervical cancer (52%), the reason for which is human papillomavirus. In 2012, approximately 270, 000 women died of RSM and over 85% of these deaths occurred in low and medium -sized countries.
Treatment
RSM screening tests for precancerous conditions and cancer among women who have no symptoms and feel completely healthy. If screening reveals precancerous 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 treatment.
Given the fact that precancerous conditions have been developing for many years, every woman aged 30-49 is recommended to be screening at least once in life and better often. Screening is effective in reducing the mortality rate of cervical cancer only in the case of a significant number of women.
Different types of screening are currently available:
- The usual Papanicolau (PAP) test and liquid cytology (LBC);
- Visual inspection using acetic acid;
- HPV High risk testing.
There are programs in developed countries that provide women with screening options, allowing you to identify most precancerous conditions in stages when they can be easily treated. Early treatment of human papillomavirus allows you to prevent 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 the short stages when symptoms develop. In addition, the treatment of the disease in such later stages is ineffective, leading to high levels of mortality from RSM in these countries.
Vaccination efficiency
The results of the clinical trials show that the two vaccines existing today are safe and very effective in preventing HPV infection 16 and 18. Both vaccines are more effective if vaccination is performed before exposure to human papillomavirus. Therefore, it is preferable to vaccination before the first sexual contact. Vaccines do not cure HPV infection or disease associated with HPV (such as cancer).
In some countries, the vaccination of boys against the human papillomavirus is introduced, taking into account the fact that it allows you to prevent genital cancer in both men and women, and one of the available vaccines also prevents the development of genital warts in men and women. In addition, boy vaccination serves to prevent HPV circulation in the adolescent and young adult population. Who recommends vaccination for girls aged 9-13 years, as this is the most effective in terms of costs, a measure of public health against cervical cancer.
HPV vaccination does not replace the cervical cancer screening. In countries where VPV vaccine is taken, screening programs may also be required. By the end of 2013, the vaccine against the human papillomavirus was introduced in 55 countries by the WHO.
Modern Mathematical Models Show That At The Coverage of Girls 12-13 Years Old, A Full Course of Primary Immunization (3 Doses) With A Vaccine Against Papillomus Infction, It isCervical Cancer by 63%, Cervical Intraepithelial Neoplasia of the Third Degree of Severity (Forenun) -By 51%, Cytological Disturbances in Age Corses to the Age Corses this. 30 years - by 27%.
Vaccines
There are currently two vaccines that protect from 16 and 18 species of human papillomavirus, causing at least 70% of the cervical cancer. These vaccines can also provide some cross protection against other, less common HPV species causing RSM. One of these vaccines also prevents HPV 6 and 11 species that cause anogenital warts.
The development and registration of vaccines against papillomavirus infection determines the possibility of primary prevention of RSM.
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 registered annually, about 270, 000 patients die.
The frequency preserves the tendency of growth.
The likelihood of CRM's disease of every woman on average in her life is 0, 53%.
Historical information and interesting facts
In the mid -seventies of the twentieth century, scientist Harold Tsur Hausen discovered that women suffering from cervical cancer were invariably infected with human papillomavirus. In 1983, he discovered the DNA of papillomavirus in a biopsy of cervical cancer and this event can be considered an opening of an oncogenic VPH-16 virus. In 2008, the Nobel Committee awarded the Nobel Prize in the field of physiology and medicine Harald Zur Hausen for the discovery that the papilloma virus could cause cervical cancer.