Group 1 - The article highlights that mosquitoes are responsible for approximately 780,000 deaths annually, making them the deadliest animals globally [1][6][5] - In China, mosquito-borne diseases such as dengue fever and malaria are on the rise, with dengue cases experiencing a significant increase in recent years [2][9][11] - The distribution of mosquitoes in China is not limited to southern provinces; several northern provinces also have high mosquito populations [15][17] Group 2 - The main mosquito-borne diseases in China include dengue fever, malaria, and Japanese encephalitis, all of which can have severe health impacts [9][11] - Dengue fever is currently the most concerning mosquito-borne disease in China, with a rapid increase in cases reported in 2023 [9][11] - The spread of mosquito-borne diseases is closely linked to economic development, population mobility, and climate change, with global dengue cases increasing approximately 30 times over the past 50 years [11] Group 3 - The most common mosquito species in China include Aedes albopictus, Culex pipiens, and Anopheles sinensis, with a total of 418 known species [19] - Mosquito activity peaks at specific times, with different species exhibiting varying feeding patterns, which can influence their impact on human populations [20][21] - Mosquito saliva contains allergens that can cause significant immune responses in humans, leading to more severe reactions to bites from certain species [25]

一系列政策"黑天鹅"，击碎了预期中的美国旅游旺年。 美国商务部国家旅游办公室发布数据显示，3月赴美游客人数同比下降11.6%。2025年前三个月，赴美 游客数量为710万人，同比减少了3.3%。 这与去年的美国旅游热度形成鲜明对比。美国商务部国际贸易署的数据显示，2024年赴美国际游客超过 7239万人次，同比增长9.1%。 不少旅游机构原本看好今年赴美游行情，认为外国游客人数会继续增长，但现在纷纷下调预期。旅游预 测公司旅游经济学（Tourism Economics）去年预测，2025年，美国国际游客数量将同比增长9%。然而 面对当下情况，该机构迅速修改预测称，美国国际游客数量将由涨转跌，同比下滑9.4%，同时国际游 客在美国的消费总额将减少90亿美元。 在赴美旅游的意愿减弱以及美国经济的不确定性增强的背景下，美国达美航空总裁豪恩斯坦（Glen Hauenstein）表示，该公司来自加拿大的预订量"大幅"下降。基于全球贸易的不确定性，该公司撤回了 2025年的盈利预测。 据统计，每年旅游业为美国经济贡献了2.3万亿美元，占美国国内生产总值（GDP）的2.97%，支撑着 950万个就业岗位。 美国商务部国家旅 ...