With the widespread use of the hepatitis B vaccine in children and the development of treatment technology, the number of hepatitis B infections in China has been gradually decreasing in recent years. At the same time, however, the problem of hepatitis C (Hepatitis C) has become apparent and increasingly important, and from time to time, a person infected with Hepatitis C virus has been discovered. So who is at risk for hepatitis C? To answer this question, we have to start from the transmission route of hepatitis C. The main transmission routes of hepatitis C include the following four aspects. 1, blood transmission: as the name suggests, the transmission occurs through blood transfusion and blood products. As early as before 1993, our country and many other countries in the world, there is no way to screen the blood for hepatitis C virus, and many of the patients who were clearly diagnosed as hepatitis C were diagnosed as “non-A, non-B hepatitis” at that time because of the low level of science and technology at that time. After screening blood donors for hepatitis C antibody (anti-HCV) since 1993, this pathway has been obviously controlled, but because the reagents are not too perfect, there are not many screening indexes, coupled with the lack of popularization of screening in some places, there are still some people infected with hepatitis C through blood transfusion, which was obviously improved in 1995. Therefore, the vast majority of hepatitis C infections due to blood transfusion in China occurred in which period before 1996. Due to the existence of window period of anti-HCV (a period of time from viral infection to the ability to detect antibodies), the unstable quality of anti-HCV test reagents and a small number of infected people do not produce anti-HCV, so far it is not possible to completely screen out HCV-positive people. Therefore, it is still possible to be infected with Hepatitis C through massive transfusion of blood and blood products. 2.Transmission through broken skin and mucous membranes: this is one of the most important modes of transmission at present, and in some areas, HCV transmission due to intravenous drug use accounts for 60%~90%. The use of non-disposable syringes and needles, dental instruments that are not strictly sterilized, endoscopes, invasive manipulation and needlesticks are also important ways of transmitting through the skin. Some traditional medical practices that may result in skin breakdown and blood exposure have also been associated with HCV transmission. In addition, sharing razors, toothbrushes, tattoos and earring piercings are also potential modes of HCV transmission via blood. 3, sexually transmitted: with HCV-infected people who have sex and sexual promiscuous behavior of people with a higher risk of HCV infection. At the same time with other sexually transmitted diseases, especially the risk of HCV infection is higher for people infected with HIV (HIV). 4, mother-to-child transmission: hepatitis C-positive mothers will HCV transmission to the newborn risk of 2%, if the mother in the delivery of hepatitis C nucleic acid (HCVRNA) positive, the risk of transmission can be as high as 4% to 7%. In combination with HIV infection, the risk of transmission increases to 20%. high replication of the HCV virus may increase the risk of transmission. 5, other ways: some HCV infected people’s transmission is unknown. Kissing, embracing, sneezing, coughing, food, drinking water, sharing tableware and cups, no skin breakage and other contacts without blood exposure generally do not spread HCV. Once we understand the transmission pathway of hepatitis C, we can basically determine who are the high-risk group of hepatitis C. They mainly include the following eight groups of people: (1) people who have been transfused with blood and blood products: especially those who have had a history of blood transfusion before 1996, which is a high-risk group. (1) People who have had blood and blood products transfusion: especially those who had a history of blood transfusion before 1996 are the high-risk group. Those who donated blood repeatedly or had a history of plasma mono-collecting (removing plasma and transfusing red blood cells back into the body) during that period are also at higher risk because of more chances of contamination. Other groups such as people who have used blood products repeatedly for blood disorders. (2) Intravenous drug addicts: Hepatitis C virus infection often occurs through the sharing of unclean syringes, which is a high risk in some areas and in certain populations. (3) Close contacts with people with hepatitis C: If a husband, wife, child, or parent in a family has hepatitis C, other close contacts are at risk for hepatitis C virus infection. However, as with hepatitis B, general contact between coworkers, using public telephones and bathrooms, taking public transportation, sharing utensils and glasses, etc., are not considered close contact and will not spread hepatitis C. (4) Infants whose mothers are hepatitis C infected: the infection may be transmitted during intrauterine infection and delivery, and it may also be transmitted to the child through breastfeeding and other close contacts after delivery. (5) People who have had sexual intercourse with hepatitis C-infected people: such as homosexuals and heterosexuals of hepatitis C-infected people, prostitutes, johns, homosexuals and other sexually promiscuous people have the possibility of transmitting and getting infected by hepatitis C. The number of people who have been infected through this route has been increasing in recent years. The number of people infected through this way has a significant upward trend in recent years, which deserves attention. (6) Organ transplant recipients: Hepatitis C infection can be caused by organ transplant donors, bone marrow infection, or large amount of intraoperative blood transfusion. (7) People on hemodialysis: repeated exposure to blood increases the risk of infection. (8) Other people: people who have had dental procedures, intramuscular or transvenous injections, acupuncture, ear piercing, tattoos, pedicures, etc., performed in poorly sterilized places, and healthcare workers who have had accidental stab wounds. So, if you or your family or friends belong to any of these high-risk groups, it is important to be aware of Hepatitis C. Diagnosing Hepatitis C is not difficult, and a lab test is all that is needed.