Browsing Tag

Infection Prevention

General Information, Microbiology

Influenza Antigen Testing (December 2024)

Influenza prevalence fluctuates seasonally, and case numbers are currently increasing throughout West Michigan. The onset of “flu season” varies year-to-year though typically begins its upswing in the month of December. It is important for providers to have an awareness of influenza prevalence (in addition to other respiratory viruses) to help guide when influenza testing should be pursued.

The use of point of care (POC) antigen testing reduces both the cost to the patient and turn-around-time as compared to lab-based molecular methods. POC antigen tests are typically available for COVID-19, influenza A/B, and as a COVID-19/influenza A/B combination test. During warmer months when influenza prevalence is negligible yet COVID-19 may be circulating, a COVID-only antigen test may be helpful for diagnosis. As influenza increases into colder months, a COVID-19/Influenza A/B combo test would act as a screen for both viruses.

POC tests generally have high analytical specificity but lack the sensitivity of nucleic acid amplification methods (e.g. PCR). For this reason, PCR testing is still recommended for hospitalized patients and for outpatients with a negative POC result if influenza is still suspected and if the result will impact clinical decision making. Influenza PCR may be ordered as a standalone test (LAB3255) or as a part of a panel alongside COVID-19 and RSV (LAB1230746).

 

Test Information

  • Influenza PCR Epic Code: LAB3255, Interface EMR Code: 11594, CPT Code 87502
  • COVID-19, Influenza A/B, RSV PCR Epic Code: LAB1230746, Interface EMR Code: 1230746, CPT: 0241U

 

Contact/Resources

Local Infection Prevention Team

Michigan Department of Health and Human Services

 

December 24, 2024 by
Test Utilization

Influenza Testing Update: April 2024

This winter, West Michigan influenza infections peaked in February 2024 and significantly declined throughout March and April 2024. Now with a low prevalence of circulating influenza, using the most sensitive diagnostic test is recommended in order to obtain accurate and actionable results. Influenza antigen testing (e.g. Sofia instrument) is no longer appropriate at this time and Influenza PCR testing should be ordered when clinically indicated.

 

Low Influenza
Prevalence		 High Influenza
Prevalence
Recommended Order Influenza PCR (LAB3255) Influenza antigen testing (e.g. Sofia instrument)
or
Influenza PCR (LAB3255)

More detailed information can be found as published by the CDC:

Algorithm to assist in the interpretation of influenza testing results and clinical decision-making during periods when influenza viruses are NOT circulating in the community, and in previous lab newsletters: Influenza Diagnosis and Test Utilization

April 30, 2024 by
Main lab, Microbiology, Referral/Sendouts

Measles Ordering and Collecting Specimens

With several suspected cases of measles within Michigan, we thought it would be an excellent time to highlight Corewell Health West’s guidance on testing suspected patients. Specimens are sent to a reference lab for testing, which must be coordinated with local public health departments. Typically an upper-respiratory swab (throat or nasopharyngeal)  is collected for PCR testing in addition to a serum for measles IgM if collection is possible.

  • Patients should not be directed to a Corewell Health Laboratory or other healthcare facility for serum collection if patient is within 4 days after the onset of rash (with onset of rash considered to be Day 0). If Day 5 of rash or later, immunocompetent patients are no longer considered contagious and may be sent to a laboratory for a serum draw.
  • Corewell Health Providers:
    • Please reach out to Corewell Health Infection Prevention (IP) via Perfect Serve to make them aware of the situation.
    • Corewell Health Infection Prevention will contact the appropriate county.
  • Non-Corewell Health Facilities:
    • The provider’s office must coordinate with the county health department that the patient lives in to obtain permission to send measles testing.
    • Visit the following link for county health department contact information: Slide 1 (michigan.gov)
      • The county will coordinate with MDHHS for testing permission.

The preferred testing specimen is a throat or nasopharyngeal swab collected in office. Corewell Health Laboratories do not collect swabs.​

For further collection and ordering instructions, please visit: Measles PCR – Laboratory Test Catalog | West

Any additional questions or concerns, please use the contact us link above or reach out to your local health department.

April 11, 2024 by