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. 2021 Dec 10;70(49):1712-1714.
doi: 10.15585/mmwr.mm7049e1.

Influenza A(H3N2) Outbreak on a University Campus - Michigan, October-November 2021

Miranda J Delahoy, Lindsey Mortenson, Laura Bauman, Juan Marquez, Natasha Bagdasarian, Joseph Coyle, Kelsey Sumner, Nathaniel M Lewis, Adam S Lauring, Brendan Flannery, Manish M Patel, Emily T Martin

Influenza A(H3N2) Outbreak on a University Campus - Michigan, October-November 2021

Miranda J Delahoy et al. MMWR Morb Mortal Wkly Rep. .

Abstract

On November 10, 2021, the Michigan Department of Health and Human Services (MDHHS) was notified of a rapid increase in influenza A(H3N2) cases by the University Health Service (UHS) at the University of Michigan in Ann Arbor. Because this outbreak represented some of the first substantial influenza activity during the COVID-19 pandemic, CDC, in collaboration with the university, MDHHS, and local partners conducted an investigation to characterize and help control the outbreak. Beginning August 1, 2021, persons with COVID-19-like* or influenza-like illness evaluated at UHS received testing for SARS-CoV-2, influenza, and respiratory syncytial viruses by rapid multiplex molecular assay.† During October 6-November 19, a total of 745 laboratory-confirmed influenza cases were identified.§ Demographic information, genetic characterization of viruses, and influenza vaccination history data were reviewed. This activity was conducted consistent with applicable federal law and CDC policy..

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Conflict of interest statement

All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Emily T. Martin reports grants from Merck, outside the submitted work. Adam S. Lauring reports personal fees from Sanofi and personal fees from Roche, outside the submitted work. No other potential conflicts of interest were disclosed.

Figures

FIGURE
FIGURE
Number of symptomatic persons who received testing for influenza A at University Health Service (N = 3,121) and percentage of tests positive for influenza A, by date of influenza test — University of Michigan, October 6–November 19, 2021 * Among persons who received testing more than once during October 6–November 19, 2021, the first influenza A–positive test result was used, or if the person never received an influenza A–positive result, the first negative test result was used. † University Health Service does not conduct influenza A testing on Sundays.
See this image and copyright information in PMC

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