The purpose of the study is to evaluate the reliability and accuracy of a newly developed point-of-care analyzer, theCytoTracker, to measure complete blood count (CBC) parameters and discriminate between viral and bacterial infections.

The purpose of the study is to evaluate the reliability and accuracy of a newly developed point-of-care analyzer, the CytoTracker, to measure complete blood count (CBC) parameters. The CytoTracker results will be compared to those from a standard benchtop analyzer (Horiba Point of Care Hematology Analyzer, ABX Micros ES 60). If successful, the data from this study would be used to support a pre-submission meeting to the FDA for the CytoTracker. In addition to validating the CytoTracker, the project will study the use of CBC parameters to distinguish between observed bacterial or viral infections in adults. Hospitalized adult subjects with suspected or confirmed viral or bacterial infections will be enrolled in the study. After enrollment a venous blood sample (baseline sample) will be collected and the CytoTracker will be used to measure CBC parameters (cell counts and population distribution). Clinical data will be abstracted from the medical record and used with the CBC parameters to develop an algorithm to distinguish between bacterial and viral infections.

Inclusion Criteria:

-COVID positive or suspected/confirmed bacterial infection (lower UTI, pneumonia, septecemia, etc). -Adults 18 years of age and older. -Meet SIRS criteria anytime during the ED presentation.

Exclusion Criteria:

• Subjects who are unable to give informed consent will be excluded
• Subjects with the following conditions will also be excluded: Known white blood cell, neutrophil, and lymphocyte disorders Active cancer patients; For solid tumors, subject will be excluded if he/she has received chemotherapy in the last 3 months.
• Subjects who are pregnant

Emergency room patients