How-does-the-flu-start-out

Where does the flu come from every year? - UChicago …

Uchicagomedicine.orgSep 14, 2016 · Where does the flu come from every year? American soldiers being treated during the 1918 Spanish flu pandemic. The source of the H1N1 strain is still up for debate, but it began spreading during World War I and infected as many as 500 million people around the world, killing between 50 and 100 million. (Image: National Library of Medicine)

https://www.uchicagomedicine.org/forefront/biological-sciences-articles/where-does-the-flu-come-from-every-year 

Where Does The Flu Come From, And Why Are We …

Abcnews.go.comSep 25, 2008 · Influenza is a virus that's spread from person to person. It originates, actually, among birds and other animals such as pigs, and new viral strains of influenza come to this country and to Europe

https://abcnews.go.com/Health/ColdandFluQuestions/flu-susceptible-flu-year/story?id=5677533 

Frequently Asked Influenza (Flu) Questions: 2021-2022

Cdc.govAnother measure would be the FluSurv-NET cumulative hospitalization rates from 2020-21 and 2019-20. The overall cumulative hospitalization rate for the 2020-21 flu season was 0.8 per 100,000. For the 2019-20 flu season, the overall cumulative end-of-season hospitalization rate was 66.2 per 100,000.

https://www.cdc.gov/flu/season/faq-flu-season-2021-2022.htm 

2020-2021 Flu Season Summary | CDC

Cdc.govOct 25, 2021 · Flu viruses are constantly changing so it’s not unusual for new flu viruses to appear each year. During the 2020-2021 flu season, there was very low circulation of seasonal flu viruses. During September 27, 2020–May 22, 2021 in the United States, 1,899 (0.2%) of 1,081,671 clinical samples tested were positive for an influenza virus (713 [37

https://www.cdc.gov/flu/season/faq-flu-season-2020-2021.htm 

The Reason for the Season: why flu strikes in winter

Sitn.hms.harvard.eduDec 01, 2014 · Flu vaccines given with a needle (i.e., flu shots) are currently made in two ways: the vaccine is made either with a) flu viruses that have been ‘inactivated’ (killed) and that therefore are not infectious, or b) using only a single gene from a flu virus (as opposed to the full virus) in order to produce an immune response without causing

https://sitn.hms.harvard.edu/flash/2014/the-reason-for-the-season-why-flu-strikes-in-winter/