流感季已至，但多地四价流感疫苗供应紧张

Group 1 - Recent announcements from vaccination points in cities like Guangzhou, Xi'an, Changzhou, and Jinan indicate a phase of tight supply or shortage of certain flu vaccines [1][3] - Different community health centers report varying shortages, with some lacking quadrivalent flu virus split vaccines and others facing shortages of quadrivalent flu subunit vaccines [1][3][5] - The demand for quadrivalent split flu vaccines has surged due to their lower price, leading to temporary supply tightness [3][5] Group 2 - As of November 5, 2023, some health centers reported limited availability of quadrivalent subunit flu vaccines, with quadrivalent split flu vaccines completely out of stock [5][6] - The increase in vaccination demand is attributed to the earlier onset of the flu season, with local disease control centers placing orders based on regional needs [6][9] - The supply of quadrivalent subunit flu vaccines is constrained by production capacity, as only Jiangsu Zhonghui Biological provides this type, with an annual production capacity of 4 million doses [9] Group 3 - The overall flu vaccine supply in China is gradually increasing, with the number of approved flu vaccines reaching 26 by July 2025, including 12 quadrivalent vaccines [7][11] - The flu vaccination rate in China remains significantly lower than in the U.S., with only 3.8% during the 2022-2023 flu season compared to 49.3% in the U.S. [11] - Forecasts suggest that China's flu vaccination rate could rise to approximately 9% to 9.5% by 2029 and further to about 15% to 15.5% by 2033, approaching levels seen in Western countries [12]