The purpose of this study is to demonstrate the safety and effectiveness of the T2Bacteria Panel by validating the clinical performance (i.e. estimated sensitivity and specificity) of the T2Bacteria Panel compared to blood culture results and/or known Bacteria positive status of prospectively collected clinical specimens and contrived (i.e. Bacteria-spiked) whole blood "clinical samples".

Inclusion Criteria:

• Subject or subject's legally authorized representative (LAR) must be able to understand, read and sign the study specific informed consent form after the nature of the study has been fully explained to them.
• Subject has had a diagnostic blood culture ordered, per routine standard of care (prospective arm only).
• Subject is between 18-95 years of age.

Exclusion Criteria:

• Subject has other co-morbid condition(s) that, in the opinion of the Investigator, could limit the subject's ability to participate in the study or impact the scientific integrity of the study.
• Subject has had previous specimens tested by the T2Bacteria Panel with valid results.
• Treatment of subject with any investigational novel drug compound within 30 days prior to the collection of T2 specimens.

Candidates participating in the prospective arm of the study will come from the hospital population who have had a blood culture ordered per routine standard of care. The contrived arm of the study is open to any participants that meet the study enrollment criteria. The study population for both arms is defined as all subjects who meet the study eligibility criteria, provide informed consent, and provide the clinical specimens under this protocol.