Group 1 - The core viewpoint of the article highlights a significant rise in flu-related stocks, with companies like Te Yi Pharmaceutical hitting the daily limit, and others like Jinshi Yao, Hualan Vaccine, and Xin Ganjing seeing increases of over 10% [1][2] - The flu activity in southern China is on the rise, with experts predicting an earlier flu season this year compared to last, and the circulating strain being different from the previous year [2][3] - The predominant strain this year is H3N2, which may lead to lower immunity in the population compared to last year's H1N1 strain, necessitating increased attention [4][5] Group 2 - Vaccination is emphasized as the most effective method to prevent flu and reduce severe cases, with recommendations for vaccination between September and November to ensure effective immunity before peak season [6][7] - The article discusses the differences between trivalent and quadrivalent flu vaccines, noting that while quadrivalent vaccines cover an additional strain, the practical difference in effectiveness is minimal [10] - High-risk groups, including children under 5, the elderly over 65, pregnant women, and those with chronic health conditions, are advised to prioritize flu vaccination [12]