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Influenza in Los Angeles County

Influenza,Flu

Photo from the Centers for Disease Control.


Also see:
-- COVID-19 in Los Angeles County
-- Notifiable Communicable Diseases & Conditions - Los Angeles County
-- When Los Angeles Last Faced a Pandemic.



Los Angeles County New Influenza Cases by 7-Day Period, 2022-2023 Flu Season

Weeks are Sunday through following Saturday. A new flu season begins in October. Numbers represent positive tests at specified Los Angeles County influenza surveillance labs.

Influenza, Flu, Cases, Los Angeles County

Los Angeles Almanac chart.


Los Angeles County's 2022-2023 flu season was its worst in at least 13 years. Within just the first two-and-a-half months of the season, the number of lab-confirmed flu cases in the county exceeded that of the previously worst flu season in 2019-2020.



Flu Season* Positive Flu Tests Influenza-Related Deaths
Total Deaths Pediatric Deaths
2022-2023 (through 9/9/2023) 28,138 65 5
2021-2022 6,205 16 0
2020-2021** 206 5 0
2019-2020†† 15,489 62 2
2018-2019 6,429 125 2
Flu Season* Positive Flu Tests Influenza-Related Deaths
Total Deaths Pediatric Deaths
2017-2018 12,429 289 2
2016-2017 6,855 77 1
2015-2016 6,702 70 3
2014-2015 5,752 54 3
2013-2014 3,953 105 4
Flu Season* Positive Flu Tests Influenza-Related Deaths
Total Deaths Pediatric Deaths
2012-2013 3,163 69 7
2011-2010 1,149 21 2
2010-2011 2,122 34 3

* Although influenza is detected year-round, according to the Centers for Disease Control, a new "flu season" begins in October and peaks during December through February. Significant activity, however, can last as late as May.
† This number represents only those tested at specified Los Angeles County influenza surveillance labs and whose results were positive.
‡ Ages 0-17
** The dramatic drop-off in reported influenza cases during this period was attributed to widespread public health practices in response to the COVID-19 pandemic, such as requirements for face coverings, social distancing, closures, etc.
†† Official summary numbers had not been provided for the end of this season, due to public health staff suddenly pressed into beomg fully occupied with COVID-19 data. Numbers presented here are cumulative tallies of weekly influenza reports for the season through Mar. 21, 2020.

Source: Acute Communicable Disease Control, Los Angeles County Department of Public Health


Red Cross Motor Squads in St. Louis drill to meet the Influenza Epidemic, 1918
Los Angeles once faced a horrific influenza outbreak.