September 28, 2018 https://www.usatoday.com/story/news/nation/2018/09/28/flu-pandemic-100-years-ago-50-million-died-could-happen-again/1423955002/ NPR: Think You Don't Need A Flu Shot? Here Are 5 Reasons To Change Your Mind Healthline: Flu Season Has Kicked In... Here’s How to Protect Yourself