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Volume 31, Number 11—November 2025

Research

Community-Driven, Text Message–Based COVID-19 Surveillance System, Los Angeles County, California, USA, 2020–2024

Jordan B. Braunfeld, Elizabeth Traub, Howard Chiou, Aryana T. Amoon, Christina Collins, Allison Joyce, Justin Buendia, Prabhu Gounder, and Annabelle de St. Maurice
Author affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, USA (J.B. Braunfeld); Los Angeles County Department of Public Health, Los Angeles, California, USA (J.B. Braunfeld, E. Traub, H. Chiou, A.T. Amoon, C. Collins, A. Joyce, J. Buendia, P. Gounder, A. de St. Maurice)

Main Article

Figure 3

Trends in COVID-like illness responses to the Angelenos in Action community-driven, text message–based COVID-19 surveillance system used in Los Angeles County, California, USA, 2020–2024, by MMWR influenza season (10). A response was designated as a COVID-like illness if the respondent indicated they were sick and answered yes to both symptom-specific questions. The colored diamonds correspond to the peak rate for each year. MMWR, Morbidity and Mortality Weekly Report; WK, week.

Figure 3. Trends in COVID-like illness responses to the Angelenos in Action community-driven, text message–based COVID-19 surveillance system used in Los Angeles County, California, USA, 2020–2024, by MMWR influenza season (10). A response was designated as a COVID-like illness if the respondent indicated they were sick and answered yes to both symptom-specific questions. The colored diamonds correspond to the peak rate for each year. MMWR, Morbidity and Mortality Weekly Report; WK, week.

Main Article

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Page created: September 23, 2025
Page updated: November 26, 2025
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