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On January 21, 1911, the American scientist Rous isolated a virus, causing sarcoma in chickens. At the same time, a viral theory arose origin of malignant tumors. Cancer was believed caused by viruses, which means it can be contagious. What are current scientific evidence of cancer infectivity? It was later many malignant viruses have been discovered neoplasms in animals – not only birds, but also mammals, reptiles and even amphibians. The study of the Routh virus and him such viruses allowed scientists to reveal the mechanisms of their influence per cell and the formation of mutated cells capable of uncontrolled division – these are the ones that form the tumor education. The discovery of viruses that can cause the formation of tumors in animals, led to the emergence of viral theory tumor growth in humans – viruses capable of cause tumors in humans, however, not with one hundred percent probability. At the same time, they started talking about the contagiousness of cancer. IN it has now been shown that it is impossible to get cancer, however cancer-causing viruses are actually transmitted from person to person. Such viruses are called oncogenic. To the most studied oncogenic viruses include human papillomavirus, human immunodeficiency virus, hepatitis B and C. viruses human papillomas In total, about 100 types of viruses are known human papillomas, but malignant neoplasms cause just a few of them. In Russia, the most common types are 16 and 18, less – types 31, 33, 35, 39, 45, 51, 52, 56, 58 and 59. They infect epithelial cells and in some cases cause them malignancy. According to statistics, by the age of 50, the papilloma virus 80% of women are affected, in 90% of cases the disease is asymptomatic, but in 3-5% of cases 10-20 years after infection long-term consequences arise – cervical cancer. Moreover, human papillomavirus can cause other forms of cancer genitals, as well as colorectal cancer and throat cancer. Virus human papillomas are sexually transmitted (also possible transmission from mother to fetus), it is highly infectious, affects both men, and women, and a condom does not always protect against infection. This is one of the most common genital infections. Hepatitis b viruses and C These DNA viruses infect liver cells, are capable of partially or fully integrate into their genome and cause transformation, which leads to liver cancer – hepatocarcinoma. By according to WHO, in 25% of patients with liver cancer, its root cause is hepatitis C. A link has also been established between the development of liver cancer and hepatitis B virus – most cases of liver cancer are reported in Southeast Asia and Africa – areas endemic for hepatitis B. According to WHO statistics, 15-25% of adults who become chronically infected in childhood, die of hepatitis B related cancer or liver cirrhosis Infection with viral hepatitis occurs mainly during sexual intercourse, blood transfusion, the use of non-sterile materials for injection, as well as in a vertical way – from mother to fetus. This is not to say that infection viral hepatitis definitely leads to liver cancer, however the probability is pretty high. Other oncogenic viruses include: Epstein-Barr virus, herpesvirus type 8, T-cell leukemia virus person. Human immunodeficiency virus HIV is not oncogenic virus, that is, it is not able to integrate into the genome cells and cause its transformation, cells affected by the virus, are dying. However, given that these are cells of the immune system, protecting the body, including from tumor growth, infection HIV significantly increases the likelihood of malignant neoplasms in patients. Most often, Kaposi’s sarcoma occurs, various types of lymphomas. Often these tumors are associated with parallel infection with oncogenic viruses – the virus Epstein-Barr, herpesvirus type 8, human papillomavirus. Facts about the contagiousness of cancer 1. Cancer is not possible, but infection with viruses that contribute to the development of malignant neoplasms, quite. 2.A few are currently known. types of oncogenic viruses, the association of which with cancer has been proven. 3. Infection with the oncogenic virus does not always lead to development cancer, but the likelihood is very high. 4. What exactly becomes a push to uncontrolled growth of cells affected by oncogenic viruses, not known. 5. Oncogenic viruses can be considered as those integrate into the genome of human cells, and those that suppress the immune system. 6. Most often infection with oncogenic viruses occurs during sexual contact, use of non-sterile materials for injection, blood transfusion, and also from the mother to the fetus. 7. Vaccines developed against some oncogenic viruses (against hepatitis B, human papillomavirus, active search for a vaccine against HIV), we can say that they protect and from the development of malignant neoplasms. 8. There are many types of malignant neoplasms, the development of which is not associated with viruses. 9. At the same time, a weakened immune system can become the cause of the development of any form of cancer, and viral infections, weakening immunity, indirectly are the reason. 10. Infection with oncogenic viruses requires increased attention from doctors and the patient himself and caution in cancer development plan. So, papilloma virus infection a person of a dangerous type in a woman requires annual PAP test – cytological examination of a smear from the cervix for exclusions of cancer transformation.
Viruses DNA Time Russia
