Group 1 - The core viewpoint of the article highlights that this year's flu strain is different from last year's, with an increase in infection rates expected due to lower immunity against the prevalent H3N2 strain compared to last year's H1N1 strain [1] - The flu season has started earlier this year, with significant increases in flu cases reported in countries like Japan, the UK, Germany, and Italy [1] - Early identification of flu symptoms is crucial, as severe cases can lead to serious complications such as pneumonia and multi-organ failure [2][3] Group 2 - Vaccination is recommended between September and November for optimal protection, although it can still be administered throughout the flu season [4] - Annual vaccination is necessary due to the rapid mutation of flu viruses, which means that the strains may differ each year [5] - High-risk groups, including children under 5, the elderly over 65, pregnant women, and those with chronic health conditions, should prioritize vaccination [7] Group 3 - The article discusses the differences between trivalent and quadrivalent flu vaccines, with the latter providing broader coverage against an additional strain [8] - Vaccination should be conducted at qualified medical institutions, such as community health service centers or hospitals [9] - Individuals exhibiting flu-like symptoms should wear masks and seek medical attention promptly rather than self-diagnosing [10]

Group 1 - Influenza is a highly contagious respiratory disease caused by the influenza virus, with the World Health Organization reporting approximately 300,000 to 650,000 deaths annually due to influenza-related respiratory diseases globally, particularly affecting high-risk groups such as pregnant women, infants, the elderly, and individuals with chronic illnesses [1] - The risk of influenza activity increases with population movement and gatherings during school openings and holidays, emphasizing the importance of timely vaccination, especially for vulnerable populations like infants [1] Group 2 - The four-valent subunit influenza vaccine, developed by Jiangsu Zhonghui Yuantong Biotechnology Co., Ltd., is recognized as a preferred choice for vaccination due to its safety and efficacy, being the first of its kind in China and an advanced third-generation influenza vaccine internationally [3] - Compared to traditional split vaccines, the subunit vaccine has a higher purity by extracting and purifying only the key antigens, hemagglutinin (HA) and neuraminidase (NA), while eliminating internal proteins and impurities, thus reducing allergic risks [3] - Clinical data indicates that the subunit vaccine has superior safety, with local adverse reaction rates in infants being 54% of that of the control group split vaccine, and fever rates in children aged 3-8 being only 46% of the control group [3] - The vaccine demonstrates good immunogenicity, effectively stimulating protective antibodies, and its safety and immunogenicity results have been recognized in the "Technical Guidelines for Influenza Vaccine Prevention and Immunization (2023-2024)" [3] - The vaccine allows for a unified dosage for individuals aged 6 months and older, simplifying outpatient procedures, and employs isotonic technology and a five-faceted micro-needle to significantly reduce injection pain and bleeding rates, enhancing the vaccination experience for infants and the elderly [3]