Performance of the BacT/Alert Virtuo Microbial Detection System for the culture of sterile body fluids: prospective multicentre study
Bibliographic record
Abstract
OBJECTIVES: Continuous monitoring blood culture systems are commonly used for sterile body fluid cultures. In this multicentre study, we evaluated the performance of the new-generation BacT/Alert Virtuo system compared to the BacT/Alert 3D and conventional culture for the recovery of microorganisms from sterile body fluids. METHODS: Peritoneal, cerebrospinal, pericardial, pleural and synovial fluids from adult patients submitted for culture were collected from three different centres. Specimens were inoculated into two bottles of the same bottle type (SA, SN, FA Plus or FN Plus) in equal volumes for simultaneous incubation in the Virtuo and 3D instruments. Each specimen was also Gram stained and seeded to solid media. RESULTS: A total of 811 specimens were inoculated to 1257 bottle pairs. The Virtuo and 3D showed equivalent recovery of clinically significant microorganisms (127/155, 81.9%, vs. 126/155, 81.3%, respectively). Solid media cultures recovered fewer pathogens than either continuous monitoring system (95/155, 61.3%, p <0.001), including significantly fewer Enterobacteriaceae and enterococci. The Virtuo was significantly faster than the 3D in median time to detection of isolates from the same specimen (12.5 (range, 2.8-101.5) hours vs. 15.5 (range, 4.3-78.5) hours, p <0.001). Direct specimen Gram stain detected the eventual pathogen in 30 (26.1%) of 115 significant positive specimens. CONCLUSIONS: The BacT/Alert Virtuo system was equivalent to the 3D system in organism recovery from sterile body fluid culture but showed faster detection of growth as a result of design enhancements.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.009 | 0.019 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".