Symphony IL-6 is a device that quantitates human IL-6 by fluorescence enzyme immunoassay (FEIA) from whole-blood specimens. Use of Symphony IL- 6 removes the need for plasma separation before testing. Symphony IL-6 comprises two components, the Symphony Fluorescence Immunoanalyzer and the Symphony IL-6 Cartridge. Whole blood is added to the cartridge and then up to six cartridges can be inserted into the immunoanalyzer. After 20 minutes a readout and printout are given with a quantitative IL-6 concentration. The used cartridges are fully enclosed and can be easily disposed of in general hospital bio-waste. Given the nature of this device and its portability, there is potential for future deployment in a near patient setting.

This study is to establish an interleukin-6 (IL-6) cutoff value using the Symphony IL-6 test for patients at high risk of severe sepsis caused by a COVID-19 and/or influenza infection.

Inclusion Criteria:

• Whole-blood specimen collected in EDTA anticoagulant tube
• Subject is 22+ years of age
• A minimum volume of 0.3 ml blood will be collected for Symphony IL-6 testing
• Subjects who have concurrently received CRP test results
• Subject is confirmed to be COVID-19 positive by an EUA or FDA cleared SARS-CoV-2 positive RT-PCR test, and/or the subject is confirmed to be influenza-A or influenza-B positive by an FDA cleared test.

Exclusion Criteria:

• Subject is receiving an anti-IL-6 treatment
• Hemolyzed specimens

We will enroll approximately 200 individuals, whole-blood specimens collected as baseline samples from hospitalized individuals with confirmed COVID-19 and/or influenza patients at the University of Michigan Medical Center, Ann Arbor, MI.