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Laboratory Influenza Page

2025-2026 Influenza Season Report  
MDHHS Laboratory Data  

The data shown here are the results obtained by the MDHHS Virology Laboratory from specimens for targeted public health testing plus surveillance testing through the Michigan Sentinel Physician and Sentinel Laboratory Programs.  The Sentinel Physician Program consists of medical provider sites from a variety of geographic locations throughout Michigan enrolled in the sentinel surveillance program. These providers represent private practice for adult and pediatric patients, as well as urgent and emergency care facilities, nursing homes and university health services. Michigan is now conducting routine influenza surveillance year-round.  Thus, MDHHS requests submission of two to three specimens for influenza A and B viral culture four times during the year: early influenza season, when influenza virus is beginning to circulate; middle season, during the peak of influenza activity; late season, as influenza activity diminishes; and in the summer months. Participation in this program is voluntary.  

The complete influenza season runs from October through April. The early/middle/late season definitions vary from year-to-year and are determined on a case-by-case basis.

Inf B 2009 A, H1 Seasonal A, H3 A, Unsubtypable LAIV
Time C N SE SW Tot C N SE SW Tot C N SE SW Tot Tot Tot
Apr 26 - May 2 0 0 0 0 0 0 0 0 0 0 1 0 1 0 2 0 0
Apr 19 - 25 0 0 0 0 0 0 0 0 1 1 0 0 2 0 2 0 0
Apr 12 - 18 1 0 5 0 6 1 0 3 0 4 3 0 3 1 7 0 0
Apr 5 - 11 5 0 7 2 14 0 0 2 0 2 5 0 10 1 16 1 0
Mar 29 - Apr 4 6 0 0 5 11 1 0 0 0 1 7 1 2 0 10 0 0
Mar 22 - 28 1 0 0 0 1 1 0 0 0 1 3 0 0 1 4 0 0
Mar 15 - 21 1 0 0 1 2 0 0 0 0 0 4 0 3 0 7 0 0
Mar 8 - 14 6 0 1 0 7 1 0 0 1 2 7 0 1 1 9 0 0
Mar 1 - 7 2 0 6 7 15 1 0 0 0 1 3 0 4 3 10 0 0
Feb 22 - 28 7 0 3 1 11 1 0 0 1 2 6 0 2 4 12 0 0
Feb 15 - 21 4 0 1 0 5 2 0 0 0 2 13 0 1 2 16 0 0
Feb 8 - 14 4 1 3 0 8 0 0 0 0 0 26 0 5 2 33 0 0
Feb 1 - 7 3 0 13 15 31 0 0 0 0 0 7 0 8 5 20 0 0
January 2026 12 0 19 14 45 2 0 1 2 5 35 2 20 23 80 2 0
December 2025 11 1 41 19 72 5 1 4 7 17 43 16 47 53 159 5 0
November 2025 2 0 34 5 41 0 0 9 4 13 20 0 24 5 49 0 0
October 2025 11 1 82 25 119 1 0 5 0 6 5 0 10 3 18 0 0
  One specimen was positive for both Influenza A H1 and Influenza A H3

   2025-2026 Guidance Documents

Influenza Test Algorithm - updated 1/2026
Influenza Guidance for Laboratories - updated 10/2025
Influenza Guidance for Healthcare Providers - updated 10/2025
Influenza Guidance for Local Health Departments - updated 10/2025
Antiviral Resistance Information - updated 10/2025


   2025-2026 Northern Hemisphere Seasonal Influenza Vaccine Components

     The egg-based vaccines contain the following components:    

          A/Victoria/4897/2022 (H1N1) pdm09-like virus
          A/Croatia/10136RV/2023 (H3N2)-like virus
          B/Austria/1359417/2021 (B/Victoria lineage)-like virus           

     The recombinant or cell-culture quadrivalent vaccines contain the following components:    

          A/Wisconsin/67/2022 (H1N1) pdm09-like virus
          A/District of Columbia/27/2023 (H3N2)-like virus
          B/Austria/1359417/2021 (B/Victoria lineage)-like virus           


    Antiviral Resistance Testing

Antiviral Resistance Information - updated 10/2025


   Test Request Form

MDHHS Viral Respiratory Test Request Form - MDHHS-6097 (New 2-24)


   Specimen Collection and Shipping

Approved specimen types for influenza testing at the MDHHS BOL: 

  • Upper respiratory tract specimens such as nasopharyngeal swabs (NP), nasal swabs (NS), throat swabs (TS), dual NP/TS swabs, nasal washes (NW), and nasal aspirates (NA)
  • Lower respiratory tract specimens such as bronchoalveolar lavage (BAL), bronchial washes (BW), tracheal aspirates (TA), sputum (PCR only), lung tissue, and viral culture 

Quick Guide for Packaging and Shipping Influenza Specimens to BOL - updated 11/15/2010 
MDHHS BOL Flu Collection and Submission Guide - DCH-0772 (Rev 02/2024)
Biological Substance, Category B Shipping Label - DCH-0800 (Rev. 1-16) 


  CDC Influenza Advisories

 


 Influenza Resources    

National influenza surveillance summary information: 

CDC Weekly Influenza Surveillance page 
The CDC Influenza page
The World Health Organization


Archived Influenza Season Data

 

Rev 05/11/2026