(79 days)
Not Found
No
The description focuses on automated RT-PCR technology and an embedded microprocessor controlling mechanical processes, with no mention of AI or ML algorithms for data analysis or interpretation.
No.
This device is an in vitro diagnostic (IVD) test intended for the qualitative detection and discrimination of influenza A and B viruses. It aids in diagnosis but does not directly treat or prevent disease.
Yes
The "Intended Use / Indications for Use" section explicitly states that the test "is intended for use as an aid in the differential diagnosis of influenza A and influenza B in humans." The "Device Description" also refers to it as an "in vitro diagnostic test."
No
The device description explicitly states that the system consists of a disposable Liat Influenza A/B Assay Tube and the Liat™ Analyzer, which is a hardware component that performs the assay steps.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Intended Use: The "Intended Use / Indications for Use" section explicitly states that the assay is for the "rapid in vitro qualitative detection and discrimination of influenza A virus and influenza B virus RNA". The term "in vitro" is a key indicator of an IVD.
- Device Description: The "Device Description" section describes the device as a "rapid, automated in vitro diagnostic test".
- Function: The device performs tests on biological specimens (nasopharyngeal swab specimens) to provide information about a patient's health status (presence of influenza A or B virus RNA). This is the core function of an IVD.
N/A
Intended Use / Indications for Use
The IQuum Liat™ Influenza A/B Assay performed on the Liat™ Analyzer is an automated multiplex real-time RT-PCR assay for the rapid in vitro qualitative detection and discrimination of influenza A virus and influenza B virus RNA in nasopharyngeal swab specimens from patients with signs and symptoms of respiratory infection in conjunction with clinical and epidemiological risk factors. The test is intended for use as an aid in the differential diagnosis of influenza A and influenza B in humans and is not intended to detect influenza C.
Negative results do not preclude influenza virus infection and should not be used as the sole basis for treatment or other patient management decisions. Conversely, positive results do not rule-out bacterial infection or co-infection with other viruses. The agent detected may not be the definite cause of disease.
Performance characteristics for influenza A were established when influenza A/H1 and A/H3 were the predominant influenza A viruses in circulation. When other influenza A viruses are emerging, performance characteristics may vary.
If infection with a novel influenza A virus is suspected based on current clinical and epidemiological screening criteria recommended by public health authorities, specimens should be collected with appropriate infection control precautions for novel virulent Influenza viruses and sent to state or local health department for testing. Viral culture should not be attempted in these cases unless a BSL 3+ facility is available to receive and culture specimens.
Product codes (comma separated list FDA assigned to the subject device)
OCC, OOI
Device Description
The Liat™ Influenza A/B Assay is a rapid, automated in vitro diagnostic test for the detection and differentiation of Influenza type A and type B viral RNA in nasopharyngeal swab (NPS) specimens in universal transport media (UTM) from patients signs and symptoms of respiratory infection. The assay targets a well-conserved region of the matrix gene of Influenza A viral RNA (Inf A target) and non-structural protein (NS) gene of Influenza B (Inf B target). An Internal Process Control (IPC) is also included. The IPC is present to control for adequate processing of the target viruses and to monitor the presence of inhibitors in the RT-PCR reactions.
The Liat Influenza A/B Assay is performed on the lab-in-a-tube technology platform. The system consists of a disposable Liat Influenza A/B Assay Tube and the Liat™ Analyzer. The Liat™ Tube uses a flexible tube as a sample vessel. It contains all required unit dose reagents prepacked in tube segments, separated by peelable seals, in the order of reagent use. Manipulating a Liat Tube, the Liat Analyzer performs all assay steps from raw sample and report assay result automatically, During the testing process, multiple sample processing actuators of the analyzer compress the Liat Tube to selectively release reagents from tube segments, move the sample from one segment to another, and control reaction volume, temperature and time to conduct sample preparation, nucleic acid extraction, target enrichment, inhibitor removal, nucleic acid elution and real-time RT-PCR. An embedded microprocessor controls and coordinates the actions of these sample processors to perform all required assay processes within the closed Liat Tube. Turnaround time from sample input to result is ~20 minutes.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
nasopharyngeal swab specimens
Indicated Patient Age Range
Not Found
Intended User / Care Setting
CLIA moderate complexity and high complexity laboratory
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Not Found
Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
Limit of Detection (LOD):
The LOD of the Liat Influenza A/B Assay was tested using 3 strains of Influenza A (A/Brisbane/10/2007, A/Brisbane/59/2007, and A/NY/01/2009) and 2 strains of Influenza B (B/Malaysia/2506/04 and B/Florida/04/06). The LOD was determined by limiting dilution studies using these titered viruses, spiked into nasopharyngeal swab (NPS) sample matrix. The LOD was defined as the lowest log virus concentration detected ≥95% of the time (at least 19 out of 20 replicates tested positive).
- Influenza A LODs: 10−2 to 10−1 TCID50/mL.
- Influenza B LODs: 10−3 to 10−1 TCID50/mL.
Reactivity:
Evaluated the ability of the Liat Influenza A/B Assay to detect influenza strains representing temporal and geographical diversity. Tested against 22 Influenza A strains (including seasonal H1, H3, and 2009 H1N1, and swine origin strains) and 10 Influenza B strains. The Liat Influenza A/B Assay detected all strains tested.
Cross Reactivity:
Evaluated potential cross-reactivity with non-influenza respiratory pathogens and other microorganisms. Tested against a panel of 31 human pathogens (bacteria at 10-106 CFU/mL, viruses at 103-105 TCID50/mL). The assay showed no cross-reactivity for the tested organisms.
Inhibition by other Microorganisms:
Evaluated whether non-influenza respiratory pathogens and other microorganisms interfere with detection of Influenza A or B. The panel of 31 human pathogens was tested (bacteria at 10-106 CFU/mL, viruses at 103-105 TCID50/mL) in the presence of Influenza A or B at 3x LOD in negative NPS matrix. Results showed no interference with detection.
Interfering Substances:
Evaluated potentially interfering substances found in respiratory specimens (e.g., mucin, blood, nasal sprays, corticosteroids, gels, lozenges, antibiotics, antivirals). Tested at medically and/or physiologically relevant concentrations with 2 influenza A strains and 2 influenza B strains at 3x LOD. Results showed no interference.
Inter-lot Precision:
Assessed variability due to Liat tube manufacturing. Three lots of Liat Influenza Assay tubes were tested with 1 Influenza A strain at C95 (LOD, n=180), C100 (4xLOD, n=60), and C0 (negative NPS matrix, n=60). All runs agreed with expected results. Imprecision in Ct from inter-lot variability was
§ 866.3980 Respiratory viral panel multiplex nucleic acid assay.
(a)
Identification. A respiratory viral panel multiplex nucleic acid assay is a qualitative in vitro diagnostic device intended to simultaneously detect and identify multiple viral nucleic acids extracted from human respiratory specimens or viral culture. The detection and identification of a specific viral nucleic acid from individuals exhibiting signs and symptoms of respiratory infection aids in the diagnosis of respiratory viral infection when used in conjunction with other clinical and laboratory findings. The device is intended for detection and identification of a combination of the following viruses:(1) Influenza A and Influenza B;
(2) Influenza A subtype H1 and Influenza A subtype H3;
(3) Respiratory Syncytial Virus subtype A and Respiratory Syncytial Virus subtype B;
(4) Parainfluenza 1, Parainfluenza 2, and Parainfluenza 3 virus;
(5) Human Metapneumovirus;
(6) Rhinovirus; and
(7) Adenovirus.
(b)
Classification. Class II (special controls). The special controls are:(1) FDA's guidance document entitled “Class II Special Controls Guidance Document: Respiratory Viral Panel Multiplex Nucleic Acid Assay;”
(2) For a device that detects and identifies Human Metapneumovirus, FDA's guidance document entitled “Class II Special Controls Guidance Document: Testing for Human Metapneumovirus (hMPV) Using Nucleic Acid Assays;” and
(3) For a device that detects and differentiates Influenza A subtype H1 and subtype H3, FDA's guidance document entitled “Class II Special Controls Guidance Document: Testing for Detection and Differentiation of Influenza A Virus Subtypes Using Multiplex Nucleic Acid Assays.” See § 866.1(e) for the availability of these guidance documents.
0
$IQ^{uum}$
IQuum, Inc. 700 Nickerson Road, Marlborough, MA 01752
Tel 508 970 0099 Fax 508 970 0119 www.lQuum.com
510(K) SUMMARY
AUG - 4 2011
| Applicant | IQuum, Inc.
700 Nickerson Road
Marlborough, MA 01752
Tel: 508-970-0099
Fax: 508-970-0119 |
|---------------------|------------------------------------------------------------------------------------------------------------------------------------|
| Contact | Lingjun Chen
Title: Vice President, Operations & Business Development
Tel: 508-970-0099 ext. 116
Email: lingjun@iquum.com |
| Summary Date | May 16, 2011 |
| Trade Name | Liat™ Influenza A/B Assay, Liat™ Analyzer |
| Common Name | Influenza A, B Panel |
| Regulation Number | 21 CFR 866.3980 |
| Classification Name | Respiratory Viral Panel Multiplex Nucleic Acid Assay |
| Predicate Device: | Cepheid Xpert® Flu Assay (K103766) |
Intended Use
The IQuum Liat™ Influenza A/B Assay performed on the Liat™ Analyzer is an automated multiplex real-time RT-PCR assay for the rapid in vitro qualitative detection and discrimination of influenza A virus and influenza B virus RNA in nasopharyngeal swab specimens from patients with signs and symptoms of respiratory infection in conjunction with clinical and epidemiological risk factors. The test is intended for use as an aid in the differential diagnosis of influenza A and influenza B in humans and is not intended to detect influenza C.
Negative results do not preclude influenza virus infection and should not be used as the sole basis for treatment or other patient management decisions. Conversely, positive results do not rule-out bacterial infection or co-infection with other viruses. The agent detected may not be the definite cause of disease.
Performance characteristics for influenza A were established when influenza A/H1 and A/H3 were the predominant influenza A viruses in circulation. When other influenza A viruses are emerging, performance characteristics may vary.
If infection with a novel influenza A virus is suspected based on current clinical and epidemiological screening criteria recommended by public health authorities, specimens should be collected with appropriate infection control precautions for novel virulent Influenza viruses and sent to state or local health department for testing. Viral culture should not be attempted in these cases unless a BSL 3+ facility is available to receive and culture specimens.
1
Device Description
The Liat™ Influenza A/B Assay is a rapid, automated in vitro diagnostic test for the detection and differentiation of Influenza type A and type B viral RNA in nasopharyngeal swab (NPS) specimens in universal transport media (UTM) from patients signs and symptoms of respiratory infection. The assay targets a well-conserved region of the matrix gene of Influenza A viral RNA (Inf A target) and non-structural protein (NS) gene of Influenza B (Inf B target). An Internal Process Control (IPC) is also included. The IPC is present to control for adequate processing of the target viruses and to monitor the presence of inhibitors in the RT-PCR reactions.
The Liat Influenza A/B Assay is performed on the lab-in-a-tube technology platform. The system consists of a disposable Liat Influenza A/B Assay Tube and the Liat™ Analyzer. The Liat™ Tube uses a flexible tube as a sample vessel. It contains all required unit dose reagents prepacked in tube segments, separated by peelable seals, in the order of reagent use. Manipulating a Liat Tube, the Liat Analyzer performs all assay steps from raw sample and report assay result automatically, During the testing process, multiple sample processing actuators of the analyzer compress the Liat Tube to selectively release reagents from tube segments, move the sample from one segment to another, and control reaction volume, temperature and time to conduct sample preparation, nucleic acid extraction, target enrichment, inhibitor removal, nucleic acid elution and real-time RT-PCR. An embedded microprocessor controls and coordinates the actions of these sample processors to perform all required assay processes within the closed Liat Tube. Turnaround time from sample input to result is ~20 minutes.
Test Operation
A nasopharyngeal swab can be collected following the user institution's standard procedures. For nasopharyngeal swab samples suspended in UTM, the user transfers 100 µl of the UTM sample into Liat Influenza A/B Assay tube. The user then scans the tube barcode to identify the test and scans sample barcode to code the sample ID using the Liat Tube is then inserted into the Liat Analyzer. The analyzer performs all test steps and outputs interpreted results in 20 minutes. A report of the interpreted results can be viewed in the View Results window, and printed directly through a USB connected printer.
No reagent preparation or addition steps are required, other than adding the sample to the Liat tube. Because all the reagents are contained within the Liat assay tube and no sample or reagent needs to be removed from the tube, cross-contamination between samples is minimized.
2
Predicate Device Comparison
Predicate Device: Cepheid Xpert® Flu Assay (K103766)
| Device: | Predicate: | |
|---|---|---|
| Item Name | Liat Influenza A/B | Cepheid Xpert Flu |
| Intended Use | The IQuum Liat™ Influenza A/B Assay | |
| performed on the Liat™ Analyzer is an | ||
| automated multiplex real-time RT-PCR | ||
| assay for the rapid in vitro qualitative | ||
| detection and discrimination of | ||
| influenza A virus and influenza B virus | ||
| RNA in nasopharyngeal swab | ||
| specimens from patients with signs and | ||
| symptoms of respiratory infection in | ||
| conjunction with clinical and | ||
| epidemiological risk factors. The test is | ||
| intended for use as an aid in the | ||
| differential diagnosis of influenza A and | ||
| influenza B in humans and is not | ||
| intended to detect influenza C. |
Negative results do not preclude
influenza virus infection and should not
be used as the sole basis for treatment or
other patient management decisions.
Conversely, positive results do not rule-
out bacterial infection or co-infection
with other viruses. The agent detected
may not be the definite cause of disease.
Performance characteristics for
influenza A were established when
influenza A/H1 and A/H3 were the
predominant influenza A viruses in
circulation. When other influenza A
viruses are emerging, performance
characteristics may vary.
If infection with a novel influenza A
virus is suspected based on current
clinical and epidemiological screening
criteria recommended by public health
authorities, specimens should be
collected with appropriate infection
control precautions for novel virulent | The Cepheid® Xpert Flu Assay is an
automated, multiplex real-time RT-
PCR assay intended for the in vitro
qualitative detection and
differentiation of influenza A,
influenza B and 2009 H1N1 influenza
viral RNA. The Xpert Flu Assay uses
nasal aspirates/washes and
nasopharyngeal swab specimens
collected from patients with signs and
symptoms of respiratory infection in
conjunction with clinical and
epidemiological risk factors. The
Xpert Flu Assay is intended as an aid
in the diagnosis of influenza.
Negative results do not preclude
influenza virus infection and should
not be used as the sole basis for
treatment or other patient management
decisions.
Performance characteristics for
influenza A were established during
the 2009-2010 influenza season when
2009 H1N1 influenza was the
predominant influenza A virus in
circulation. When other influenza A
viruses are emerging, performance
characteristics may vary.
If infection with a novel influenza A
virus is suspected based on current
clinical and epidemiological screening
criteria recommended by public health
authorities, specimens should be
collected with appropriate infection
control precautions for novel virulent
influenza viruses and sent to state or
local health department for testing.
Viral culture should not be attempted in these cases unless a BSL 3+ facility |
| | | |
| | cases unless a BSL 3+ facility is | |
| | available to receive and culture | |
| | specimens. | |
| | Device: | Predicate: |
| Item Name | Liat Influenza A/B | Cepheid Xpert Flu |
| Regulation | 21 CFR 866.3980 | 21 CFR 866.3332 |
| Product Code | OCC, OOI | OQW, OCC, OOI |
| Assay Target | Influenza A
Influenza B | Influenza A
Influenza B
Influenza A subtype 2009 H1N1 |
| Sample Type | Nasopharyngeal Swab | Nasopharyngeal Swab
Nasal aspirates/washes |
| Internal Control | Yes | Yes |
| Influenza A Viral
Target | Matrix gene | Matrix gene |
| Influenza B Viral
Target | Non-structural protein (NSP) gene | Hemagglutinin gene |
| Assay Instrument | LiatTM Analyzer | GeneXpert instruments |
| Self-contained
System | Integrated PC, software, and touch-
screen display | External PC computer and software
for running tests and viewing the
results |
| All Assay
Reagents
Contained in
Disposable | No manual reagent addition required | Requires manual dispensing of
Binding Reagent into the chamber
with the small opening of the Xpert
Flu Assay Cartridge |
| Automated Assay | Yes, sample preparation, amplification,
detection and result interpretation | Yes, sample preparation,
amplification, detection and result
interpretation |
| Extraction Method | Sample preparation integrated in Liat Tube
and Liat Analyzer | Sample preparation integrated in
GeneXpert Cartridge and GeneXpert
Instrument |
| Assay Method | RT-PCR for detecting the presence /
absence of viral RNA in clinical
specimens | RT-PCR for detecting the presence /
absence of viral RNA in clinical
specimens |
| Detection
Technique | Multiplex assay using different reporter
dyes for each target | Multiplex assay using different
reporter dyes for each target |
| Result
Interpretation | Automated | Automated |
| Assay Result | Qualitative | Qualitative |
| Laboratory Users | CLIA moderate complexity and high
complexity laboratory | CLIA moderate complexity and high
complexity laboratory |
| Time-to-result | ~20 minutes | ~75 minutes |
3
:
4
Substantial Equivalence
Limit of Detection
The Limit of Detection (LOD) of the Liat Influenza A/B Assay was tested using 3 strains of Influenza A (A/Brisbane/10/2007, A/Brisbane/59/2007, and A/NY/01/2009) and 2 strains of Influenza B (B/Malaysia/2506/04 and B/Florida/04/06). The LOD was determined by limiting dilution studies using these titered viruses. The viruses were spiked into nasopharyngeal swab (NPS) sample matrix, and then tested using the Liat Influenza A/B Assay. The LOD was determined as the lowest log virus concentration that was detected ≥95% of the time (i.e. log concentration at which at least 19 out of 20 replicates tested positive). The LOD for 3 strains of Influenza A were 102 to 101 TCID50/mL, while those for the 2 strains of Influenza B were 103 to 10" TCID50/mL.
| Virus Strain | LOD (TCID50/mL) |
|---|---|
| A/Brisbane/10/2007 | 10-1 |
| A/Brisbane/59/2007 | 10-2 |
| A/NY/01/2009 | 10-1 |
| B/Florida/04/06 | 10-1 |
| B/Malaysia/2506/04 | 10-3 |
Reactivity
Reactivity study evaluates the ability of the Liat Influenza A/B Assay to detect influenza strains representing temporal and geographical diversity. The Liat Influenza A/B Assay was evaluated for reactivity with 22 Influenza A strains and 10 Influenza B strains. Influenza A strains included 8 seasonal Influenza A/H1 strains, 8 seasonal Influenza A/H3 strains, 3 Influenza A 2009 H1N1 strains, 3 swine origin Influenza A strains. The Liat Influenza A/B Assay detected all strains tested.
| Influenza Strain | Type / Subtype | Test
Concentration | Inf A
Result | Inf B
Result | Viral/Bacterial pathogen | Test concentration | Inf A Result | Inf B Result | Pathogen | Pathogen
Concentration | A/Brisbane/59/07
Inf A Result | A/Brisbane/59/07
Inf B Result | B/Malaysia/2506/04
Inf A Result | B/Malaysia/2506/04
Inf B Result |
|-------------------------|----------------------------|--------------------------|-----------------|-----------------|------------------------------------|--------------------|--------------|--------------|------------------------------------|-----------------------------|----------------------------------|----------------------------------|------------------------------------|------------------------------------|
| A/Brisbane/59/2007 | Influenza A, seasonal H1 | 8.0× $10-3$ TCID50/mL | + | - | Adenovirus Type 1 | 8.9×105 TCID50/mL | - | - | Adenovirus Type 1 | $8.9 \times 10^5$ TCID50/mL | + | - | - | + |
| A/New Caledonia/20/99 | Influenza A, seasonal H1 | 1.0× $102$ TCID50/mL | + | - | Adenovirus Type 7 | 4.5×104 TCID50/mL | - | - | Adenovirus Type 7 | $4.5 \times 10^4$ TCID50/mL | + | - | - | + |
| A/Solomon Island/3/2006 | Influenza A, seasonal H1 | 5.0× $10-2$ TCID50/mL | + | - | Human Coronavirus 229E | 1.4×103 TCID50/mL | - | - | Human Coronavirus 229E | $1.4 \times 10^3$ TCID50/mL | + | - | - | + |
| A/Mal/302/54 | Influenza A, seasonal H1 | 1.0× $103$ TCID50/mL | + | - | Human Coronavirus OC43 | 7.9×104 TCID50/mL | - | - | Human Coronavirus OC43 | $7.9 \times 10^4$ TCID50/mL | + | - | - | + |
| A/Denver/1/57 | Influenza A, seasonal H1 | 5.0× $102$ TCID50/mL | + | - | Enterovirus | 1×105 TCID50/mL | - | - | Enterovirus | $1 \times 10^5$ TCID50/mL | + | - | - | + |
| A/FM/1/47 | Influenza A, seasonal H1 | 1.0× $102$ TCID50/mL | + | - | Human Parainfluenza Type 1 | 2.8×103 TCID50/mL | - | - | Human Parainfluenza Type 1 | $2.8 \times 10^3$ TCID50/mL | + | - | - | + |
| A/PR/8/34 | Influenza A, seasonal H1 | 2.5× $101$ TCID50/mL | + | - | Human Parainfluenza Type 2 | 1.4×105 TCID50/mL | - | - | Human Parainfluenza Type 2 | $1.4 \times 10^5$ TCID50/mL | + | - | - | + |
| A/Weiss/43 | Influenza A, seasonal H1 | 2.5× $103$ TCID50/mL | + | - | Human Parainfluenza Type 3 | 1.6×105 TCID50/mL | - | - | Human Parainfluenza Type 3 | $1.6 \times 10^5$ TCID50/mL | + | - | - | + |
| A/Brisbane/10/2007 | Influenza A, seasonal H3 | 1.0× $10-1$ TCID50/mL | + | - | Measles | 7.9×104 TCID50/mL | - | - | Measles | $7.9 \times 10^4$ TCID50/mL | + | - | - | + |
| Influenza Strain | Type / Subtype | Test Concentration | Inf A Result | Inf B Result | Human Metapneumovirus | 7×103 TCID50/mL | - | - | Human Metapneumovirus | $7 \times 10^3$ TCID50/mL | + | - | - | + |
| A/Alice | Influenza A, seasonal H3 | 5.0× $10^1$ TCID50/mL | + | - | Mumps virus | 7.9×104 TCID50/mL | - | - | Mumps virus | $7.9 \times 10^4$ TCID50/mL | + | - | - | + |
| A/MRC2 | Influenza A, seasonal H3 | 1.0× $10^2$ TCID50/mL | + | - | Respiratory syncytial virus type B | 1.4×104 TCID50/mL | - | - | Respiratory syncytial virus type B | $1.4 \times 10^4$ TCID50/mL | + | - | - | + |
| A/Hong Kong/8/68 | Influenza A, seasonal H3 | 2.0× $10^1$ TCID50/mL | + | - | Rhinovirus Type 1A | 1.6×105 TCID50/mL | - | - | Rhinovirus Type 1A | $1.6 \times 10^5$ TCID50/mL | + | - | - | + |
| A/Victoria/3/75 | Influenza A, seasonal H3 | 2.5× $10^1$ TCID50/mL | + | - | Cytomegalovirus | 4.5×104 TCID50/mL | - | - | Cytomegalovirus | $4.5 \times 10^4$ TCID50/mL | + | - | - | + |
| A/Wisconsin/67/05 | Influenza A, seasonal H3 | 5.0× $10^1$ TCID50/mL | + | - | Epstein Barr virus | 1.9×105 copies/mL | - | - | Epstein Barr virus | $1.9 \times 10^5$ copies/mL | + | - | - | + |
| A/Port Chalmers/1/73 | Influenza A, seasonal H3 | 5.0× $10^2$ TCID50/mL | + | - | Bordetella pertussis | 1.8×105 CFU/mL | - | - | Bordetella pertussis | $1.8 \times 10^5$ CFU/mL | + | - | - | + |
| A/Aichi/2/68 | Influenza A, seasonal H3 | 2.0× $10^2$ CEID50/mL | + | - | Chlamydia pneumoniae | 8×104 TCID50/mL | - | - | Chlamydia pneumoniae | $8 \times 10^4$ TCID50/mL | + | - | - | + |
| A/NY/01/2009 | Influenza A, 2009 H1N1 | 1.0× $10^1$ TCID50/mL | + | - | Corynebacterium sp. | 5.0×106 CFU/mL | - | - | Corynebacterium sp. | $5.0 \times 10^6$ CFU/mL | + | - | - | + |
| A/NY/02/2009 | Influenza A, 2009 H1N1 | 2.5× $10^2$ TCID50/mL | + | - | Escherichia coli | 6.6×106 CFU/mL | - | - | Escherichia coli | $6.6 \times 10^6$ CFU/mL | + | - | - | + |
| A/NY/03/2009 | Influenza A, 2009 H1N1 | 4.0× $10^1$ TCID50/mL | + | - | Haemophilus influenzae | 3×106 CFU/mL | - | - | Haemophilus influenzae | $3 \times 10^6$ CFU/mL | + | - | - | + |
| A/New Jersey/8/76 | Influenza A, H1N1 non 2009 | 1.0× $10^1$ TCID50/mL | + | - | Lactobacillus sp. | 1.6×106 CFU/mL | - | - | Lactobacillus sp. | $1.6 \times 10^6$ CFU/mL | + | - | - | + |
| A/Swine/1976/31 | Influenza A, H1N1 non 2009 | 2.0× $10^1$ TCID50/mL | + | - | Legionella pneumophila | 7×106 CFU/mL | - | - | Legionella pneumophila | $7 \times 10^6$ CFU/mL | + | - | - | + |
| A/Swine/lowa/15/30 | Influenza A, H1N1 non 2009 | 2.0× $10^2$ TCID50/mL | + | - | Moraxella catarrhalis | 5.8×106 CFU/mL | - | - | Moraxella catarrhalis | $5.8 \times 10^6$ CFU/mL | + | - | - | + |
| B/Florida/04/06 | Influenza B | 8.0× $10^{-2}$ TCID50/mL | - | + | Neisseria meningitidis | 3.2×106 CFU/mL | - | - | Neisseria meningitidis | $3.2 \times 10^6$ CFU/mL | + | - | - | + |
| B/Malaysia/2506/04 | Influenza B | 2.0× $10^{-3}$ TCID50/mL | - | + | Neisseria sp. | 1.8×106 CFU/mL | - | - | Neisseria sp. | $1.8 \times 10^6$ CFU/mL | + | - | - | + |
| B/Florida/7/04 | Influenza B | 5.0× $10^{-2}$ TCID50/mL | - | + | Pseudomonas aeruginosa | 1.6×106 CFU/mL | - | - | Pseudomonas aeruginosa | $1.6 \times 10^6$ CFU/mL | + | - | - | + |
| B/Allen/45 | Influenza B | 5.0× $10^1$ CEID50/mL | - | + | Staphylococcus aureus | 4.5×106 CFU/mL | - | - | Staphylococcus aureus | $4.5 \times 10^6$ CFU/mL | + | - | - | + |
| B/GL/1739/54 | Influenza B | 2.0× $10^1$ TCID50/mL | - | + | Staphylococcus epidermidis | 6×106 CFU/mL | - | - | Staphylococcus epidermidis | $6 \times 10^6$ CFU/mL | + | - | - | + |
| B/Taiwan/2/62 | Influenza B | 5.0× $10^{-2}$ TCID50/mL | - | + | Streptococcus pneumoniae | 1.9×106 CFU/mL | - | - | Streptococcus pneumoniae | $1.9 \times 10^6$ CFU/mL | + | - | - | + |
| B/Maryland/1/59 | Influenza B | 5.0× $10^3$ TCID50/mL | - | + | Streptococcus pyogenes | 3.7×106 CFU/mL | - | - | Streptococcus pyogenes | $3.7 \times 10^6$ CFU/mL | + | - | - | + |
| B/Mass/3/66 | Influenza B | 1.0× $10^1$ TCID50/mL | - | + | Streptococcus salivarius | 4.3×106 CFU/mL | - | - | Streptococcus salivarius | $4.3 \times 10^6$ CFU/mL | + | - | - | + |
| B/HongKong/5/72 | Influenza B | 2.5× $10^1$ TCID50/mL | - | + | | | | | | | | | | |
| B/Lee/40 | Influenza B | 1.0× $10^0$ TCID50/mL | - | + | | | | | | | | | | |
5
6
Cross Reactivity
Cross reactivity study evaluates the Liat Influenza A/B Assay's potential cross-reactivity with non-influenza respiratory pathogens and other microorganisms with which the majority of the population may have been infected. The Liat assay was evaluated against a panel of 31 human pathogens. Bacteria were tested at 10-106 CFU/mL. Viruses were tested at 103-105 TCID56/mL. The Liat Influenza A/B Assay showed no cross reactivity for the tested organisms.
7
Inhibition by other Microorganisms
Interfering microorganism study evaluates whether non-influenza respiratory pathogens and other microorganisms with which the majority of the population may have been infected can interfere in the detection of Influenza A or B by the Liat assay. The panel of 31 human pathogens tested in the cross-reactivity study was tested for potential interference. Bacteria were tested at 10-106 CFU/mL and viruses were tested at 103-105 TCID50/mL in the presence of either A/Brisbane/59/2007 or B/Malaysia/2506/04 at 3x LOD concentration in negative NPS matrix. Results show that the presence of the tested microorganisms did not interfere with the detection of Inf A or Inf B.
8
Interfering Substances
The Liat Influenza A/B Assay was evaluated with potentially interfering substances that may be encountered in respiratory specimens. Medically and/or physiologically relevant concentrations of potential interferents were tested with 2 influenza A strains and 2 influenza B strains at 3x LOD (10-10-2 TCID50/mL). Results showed that substances tested did not interfere in the detection of influenza A and B strains.
| Potential Interferent | Active Ingredient | Concentration. |
|---|---|---|
| Mucin | ||
| Bovine submaxillary gland, type I-S | Purified mucin protein | 0.1 mg/ml and |
| 25 mg/ml | ||
| Blood | - | 5% (v/v) |
| Nasal spray - Afrin | Oxymetazoline | 5% (v/v) |
| Nasal corticosteroids - Veramyst | Fluticasone | 5% (v/v) |
| Nasal gel – Zicam | Galphimia glauca, Histaminum | |
| hydrochloricum, Luffa operculata, Sulphur | 5% (v/v) | |
| Throat lozenges, oral anesthetic and | ||
| analgesic - Cepacol | Benzocaine, Menthol | 5 mg/ml |
| Antibiotic, nasal ointment - Bactroban | Mupirocin | 5 mg/ml |
| Antiviral drug – Relenza | Zanamivir | 5 mg/ml |
| Antiviral drug - Tamiflu | Oseltamivir | 7.5 mg/ml |
| Antimicrobial, systemic | Tobramycin | 4 µg/ml |
Inter-lot Precision
Inter-lot precision assesses the Liat tube manufacturing process as a potential source of assay variability. Three lots of Liat Influenza Assay tubes were tested with 1 Influenza A strain at C95 (LOD, n=180), C100 (4xLOD, n=60) and C0 (negative NPS matrix, n=60). Results from all runs agreed with expected results. Imprecision in Ct from inter-lot variability was