The United States Centers for Disease Control and Prevention (CDC) began counting the 2017–2018 "flu season" as October 2017, and by early February 2018, ...... On 10 February 2018, Bloomberg reported that influenza in the United States was killing up to 4,000 Americans a week, ....... In the first week of February, deaths from influenza and pneumonia were responsible for one of every ten deaths in the US, with 4,064 from pneumonia or influenza recorded in the third week of 2018, according to CDC data. The CDC also reported 63 child deaths at that point, half of which were not considered medically high risk, ........
According to the Centers for Disease Control and Prevention, during the 2017–2018 season the percentage of deaths attributed to pneumonia and influenza (P&I) was at or above the epidemic threshold for 16 consecutive weeks. Nationally, mortality attributed to P&I exceeded 10.0% for four consecutive weeks, peaking at 10.8% during the week ending January 20, 2018. A preliminary estimate (September 2018) attributed more than 80,000 US deaths to influenza this season, but this was later revised down to 52,000 in light of more complete information. While 186 pediatric deaths were reported to the CDC, it is estimated that there were in reality more than 600 total pediatric deaths nationwide related to influenza.
过度训练综合症 (OTS) 发生在运动员进行剧烈训练但表现下降的情况下。OTS 的一个表现是免疫功能受到抑制，上呼吸道感染 (URTI) 的发病率增加。URTIs 发病率的增加也与高强度训练以及过度运动 (EE) 有关，例如马拉松，在赛后 3-72 小时之间表现出来。