Recently, a case of H3N8 was reported in Zhongshan City, Guangdong Province. The Chinese Center for Disease Control and Prevention rechecked the case samples and found that the H3N8 avian influenza virus nucleic acid was positive. To this end, Li Yan, Deputy Director of the Guangdong Provincial Center for Disease Control and Prevention (hereinafter referred to as "Guangdong CDC"), responded: "Currently, all human infections with H3N8 have been detected as sporadic cases. At this stage, the risk of transmission of the virus is low, and no human to human transmission has been detected.". However, the public should not take it lightly. When purchasing and handling poultry, it is necessary to pay attention to protection. At this stage, the risk of transmission of H3N8 avian influenza is low. The reporter learned that the case reported in Zhongshan City this time is a 56-year-old woman with a history of basic diseases such as multiple myeloma, a history of exposure to live birds before the onset, and a history of wild bird activity around her home. Guangdong CDC has instructed Zhongshan City to carry out epidemiological investigation, informant tracking management, screening of epidemic related sites, on-site disinfection and sterilization and other epidemic disposal work according to relevant plans. It is worth noting that the case reported in Zhongshan City is the third reported case of human infection with H3N8 avian influenza in China. In 2022, there were cases of human infection with H3N8 subtype avian influenza in Henan Province and Hunan Province in China. According to Li Yan, the H3N8 subtype of influenza virus has been detected in poultry, horses, dogs, pigs, seals, and other animals, with few human infections found. "Currently, all human infections with H3N8 have been detected as sporadic cases, with a history of exposure to live birds before the onset of the disease. Health monitoring of close contacts and co exposures has not found any new cases, suggesting that the risk of transmission of the virus is low at this stage." What is H3N8, which has less infectious symptoms caused by H3N8 avian influenza? What are the meanings of the letters H, N, and numbers 3, 8? Li Yan gave a popular scientific answer to the above question: H3N8 is a type of avian influenza, an infectious disease caused by a subtype of influenza A virus. Among them, H and N represent two proteins on the surface of the avian influenza virus. H is hemagglutinin, which can cause the virus to adhere and invade the host cell, just like the key for the virus to invade the cell; N is a neuraminidase that can help the virus to be released from the host cell, enabling it to spread within the host body. Due to frequent antigenic variations of influenza viruses, new antigenic components have emerged, forming many new virus strains. To facilitate identification and epidemiological investigation, numerical symbols are used to indicate different types and subtypes of virus strains, which have different antigenicity and pathogenicity. Experts say that according to the variation of glycoproteins, H is divided into different types from H1 to H18, and N is divided into different types from N1 to N11. Among them, H5 and H7 are highly pathogenic, and H3 subtypes cause relatively mild symptoms of infection. In addition to H3N8, there are currently subtypes of avian influenza that have been infected by humans, including H5N6, H5N1, H9N2, H7N7, H7N9, H10N3, H10N8, and H5N8. After infection with avian influenza, patients typically exhibit influenza like symptoms at the initial stage, such as fever, cough, and reduced sputum, which can be accompanied by headaches, muscle soreness, and general discomfort. The condition of critically ill patients develops rapidly, often presenting with severe pneumonia and other manifestations. "Among them, humans are infected with subtypes such as H5N1 and H5N6