Viral hepatitis is hepatitis caused by viruses and is divided into seven types of viral hepatitis, according to their virus series, from A to G. In addition, some less common viruses that infect the body can also cause viral hepatitis, such as EBV, cytomegalovirus, yellow fever virus, and certain enteroviruses. They can cause swelling of the liver cells and are somewhat infectious. Among them, hepatitis A and E can be transmitted through the digestive tract, and sharing food has the possibility of transmission; while hepatitis B and C are transmitted through body fluids, blood and mother-to-child transmission. If the virus is active, the patient needs to go to a specialist hospital for examination and treatment. Once the virus has entered the stable stage or is simply a carrier, including hepatitis B major and minor triplets, in daily life, work, such as in the same room, shaking hands, hugging, dining at the same table, sharing toilets and other non-blood-exposed contact, generally will not be infectious. Therefore, do not alienate colleagues, friends or even family members because they are carriers of hepatitis B or C virus. Non-viral hepatitis In addition to hepatitis caused by hepatitis viruses, there are many causes of liver inflammation that are virologically negative and often non-infectious, such as non-alcoholic steatohepatitis, alcoholic hepatitis, drug-related hepatitis, and autoimmune hepatitis. They sometimes exhibit symptoms similar to viral hepatitis, and patients often have weakness, nausea, loss of appetite, abdominal distension, discomfort in the liver area, yellow urine and yellow eyes, and may also show abnormal liver function such as elevated transaminases. Sometimes patients may have no obvious physical discomfort and only have abnormally elevated transaminases found during routine physical examinations. Although these hepatitis are not contagious, the possibility of cirrhosis still exists, so they also need to actively receive regular treatment. The most common of these is steatohepatitis, which is a disease caused by impaired fat metabolism in liver cells and is more common in obese people, long-term alcohol drinkers, and those who prefer to eat high-calorie, high-fat foods. Generally speaking, we can still treat the disease by improving the diet, losing weight, and quitting alcohol. The second is drug-related hepatitis. The liver is the body’s largest “chemical factory”, not only is it an important organ for processing normal metabolites in the body, but it is also the organ for metabolizing and transforming (i.e. detoxifying) all drugs. During the metabolism of drugs, many toxic chemicals may directly or indirectly damage liver cells and cause inflammation. The most common hepatotoxic drugs are: anti-inflammatory drugs (erythromycin, tetracycline, etc.), anti-tuberculosis drugs (rifampin, isoniazid, etc.), antipyretic and analgesic drugs (aspirin, paracetamol, etc.), and hypoglycemic drugs (euglycemia, bethanechol, etc.). People generally believe that Chinese medicine is safe and reliable, but in fact many Chinese medicines have hepatotoxicity, such as neem, lei gong teng, etc. The third is alcoholic hepatitis, with the development of the economy, the improvement of living standards, people’s dietary habits change, which in turn, the intake of alcohol has increased dramatically. Alcohol not only has direct toxicity to the liver, but also disrupts liver metabolism and causes abnormal liver function. As the amount of alcohol consumed increases and the age of alcohol lengthens, some studies have concluded that two or two high level liquors a day, persisted for 5 years, will lead to alcoholic hepatitis; persisted for 20 years, will most likely lead to alcoholic cirrhosis. The fourth is autoimmune hepatitis, which is a hepatitis related to abnormal autoimmune response and is more prevalent in young women. The diagnosis is clear if the body is not well and the laboratory tests are negative for viral indicators and positive for autoimmune indicators (anti-nuclear antibodies, anti-smooth muscle antibodies, etc.). Also autoimmune hepatitis often coexists with other autoimmune diseases, such as dry syndrome, rheumatoid arthritis, etc. Other causes of non-viral hepatitis include Wilson’s disease, metabolic or congenital disorders such as hemochromatosis and alpha 1 antitrypsin deficiency, and hepatic manifestations of systemic diseases. Viral hepatitis is becoming a huge threat to human public health because of its infectious nature and the large number of people infected worldwide, and we need to prevent it at all times. However, there is no need to talk about “liver”, especially with the introduction of the hepatitis B vaccine, the incidence of hepatitis B has declined worldwide. It is important to know that there are many other factors besides the virus that can cause hepatitis, but they are not contagious. Therefore, we need to take the opportunity of World Hepatitis Day to shout “Hepatitis is not always contagious!”