Cancer is not contagious and there are no cancer viruses, but some viral infections do cause cancer

Cancer virus, the first impression is that cancer is spread by the virus, in fact, cancer is not contagious. I think the person who asked this question may be asking what viruses can cause cancer? It is true that in life there are some people who live together with the same disease or tumor. In addition to their own genes, there are also some living habits.

Cancer occurs when the proto-oncogene or tumor suppressor gene of normal cells in the human body is activated or inhibited under the action of internal and external factors. These abnormal changes exceed the ability of the human immune system to recognize, clear and repair, so that it can reproduce indefinitely. eventually form a tumor. Viruses are one of the external causes.

Viruses are tiny, simple organisms that rely on a host to reproduce. In life, many of us with low immunity will be infected by rhinovirus, adenovirus, influenza virus, etc. to cause symptoms and be cleared. It can also exist in the human body for a long time and cause chronic inflammation, such as hepatitis B virus, hepatitis C virus, etc. Existing medical knowledge data does suggest that some viruses are closely related to the occurrence and development of tumors, which may be the "cancer virus" in question.

1. HBV and HCV

China is a big country with hepatitis. Because of our lack of medical knowledge and unhealthy lifestyle in the past, there are a large number of hepatitis virus carriers in China. If the hepatitis virus is inactive in the body, it can coexist peacefully with the host. If a large number of replications in the body cause acute and chronic hepatitis and further develop liver cirrhosis, the risk of liver cancer is greatly increased. Some data show that hepatitis B cirrhosis increases the risk of liver cancer by 1000 times compared with normal people, and hepatitis C also has 9.6-33.5% of hepatitis C cirrhosis can develop into liver cancer within 20 years.

Both hepatitis B virus and hepatitis C virus can be transmitted through blood, body fluids and sexual intercourse. In daily life, it is necessary to avoid sharing injection needles and sharing personal items such as toothbrushes, razors, towels, etc. In addition, breast milk can also be transmitted, and hepatitis B mothers should pay attention.

2. Human papillomavirus (HPV)

Human papillomavirus is a tiny DNA virus that mainly infects human epidermis and mucosal tissues. Hundreds of HPV viruses have been isolated, causing a variety of malignant tumors. The most common is cervical cancer, and its high-risk types include 1, 2, 6, 11, 16, 18, 31, 33 and 35. With the research on this virus, bivalent, tetravalent and 9 types have been developed. 90% of cervical cancers can be prevented by 9 valent vaccines. In addition, HPV-16 and 18 can also cause throat cancer, and HPV-4 has the risk of causing Burkitt lymphoma, Hodgkin lymphoma, and nasopharyngeal cancer. The virus is more susceptible to infection in life, such as sharing contaminated bathtubs, towels, toilets, or trauma, and it is transmitted from mother to child. Fortunately, with the improvement of the health awareness of the Chinese people, people are paying more and more attention to prevention, and the census of female malignant tumors, such as TCT (cervical thin-layer liquid-based cytology) and HPV virus detection, can detect high-risk groups at an early stage. intervention.

3. EB virus

Epstein-Barr virus is one of the human herpes viruses with a high infection rate. Some articles suggest that 90% of adults have been infected for life, but most of them will produce antibodies and coexist with the human body for a long time. When the body's immunity is low, the latent EB virus can activate the replication and act together with other factors to induce cancer, such as nasopharyngeal cancer, lymphoma, gastric cancer, lung cancer, breast cancer, cervical cancer, etc. The virus is mainly transmitted through saliva, so avoiding the cross-use of personal items and the use of public chopsticks are more effective prevention methods.

4. HIV (HIV)

HIV can be transmitted through mother-to-child transmission, sexual contact, transfusion of HIV-contaminated blood, sharing of contaminated injection needles, drug use, tooth extraction with incomplete disinfection, tattooing and other medical and aesthetic methods. Infection with the virus can lead to partial or complete loss of host immune function, secondary infection or induction of tumors, the most common tumor being Kaposi's sarcoma.

5. Human T-cell tropism virus

Human T-cytotropic viruses are a class of carcinogens, including types 1 and 2. Type 1 induces adult T-cell leukemia/lymphoma, and type 2 induces T-hairy cell/megamyelocytic leukemia. It can be transmitted to each other through breast milk, sexual contact and close family contact. Although there is currently no effective treatment for the virus, its tumor-inducing mechanism is a complex sporadic mechanism, and nearly 95% of the infected population will not develop the disease.

To sum up, the above viruses have the risk of inducing cancer, but the occurrence of cancer is related to a variety of factors, and it is necessary to strengthen physical fitness in addition to daily attention to prevention.

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