What is 2017–2018 United States flu season?
The '''2017-2018 flu season''' was a [[flu]] season of high severity in the [[United States]]. Influenza-like illness (ILI) has a high rate of outpatient and emergency clinic visits, and a high rate of influenza-related hospitalizations, and influenza activities have been on the rise for a long period of time and are widely distributed geographically. In [[2017]], the Centers for Disease Control and Prevention began using a new method to classify seasonal severity and applied the method to the seasons from 2003-2004 to 2016-2017. The 2017-18 season was the first season to be classified as highly serious among all age groups. == Origin == In the 2017-2018 season, influenza-like illness (ILI) activities began to increase in November, and reached a long period of high activity nationwide in January and February, and continued until the end of March. The peak of ILI was 7.5%, the highest percentage since the 2009 influenza pandemic (7.7%). Influenza-like illness (ILI) reached or exceeded the national benchmark for 19 weeks, making 2017-2018 one of the longest seasons in recent years. == Infections and Deaths == According to the US [[Centers for Disease Control and Prevention]] (CDC), there are no reports of childhood flu deaths nationwide. To monitor influenza-related deaths of all ages, the CDC tracks deaths caused by pneumonia and influenza (P&I) through the National Center for Health Statistics (NCHS) mortality reporting system. The system tracks the proportion of death certificates that list pneumonia or influenza as a potential cause of death. The system provides an overall indication of whether influenza-related mortality has increased, but does not provide an exact number to indicate the number of deaths from influenza. During the 2017-2018 season, the percentage of deaths due to pneumonia and influenza (P&I) reached or exceeded the epidemic threshold for 16 consecutive weeks. {{DEFAULTSORT:2017-2018 United States flu season}} [[Category:Influenza]] [[Category:2017 in the United States]] [[Category:2018 in