Novel Assays for Detection of Influenza Virus

Influenza A Virus Clinical Trial

Official title:

Evaluation of Novel Molecular Assays for the Detection of Influenza Virus

Clinical Trial Details — Status: Withdrawn

Administrative data

• NCT number: NCT03924284
• Other study ID #: FluA_20190110
• Status: Withdrawn
• Start date: April 18, 2019
• Est. completion date: July 30, 2019

Study information

• Verified date: April 2019
• Source: The University of Hong Kong
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

Seasonal influenza virus causes an estimated 0.3-0.6 million deaths per year. Avian influenza virus H5N1, H7N9 and H5N6 has fatality rate of over 30%. Swine influenza viruses from pigs have also infected humans.

Molecular assays are now used routinely in the detection of influenza viruses. The M gene is often used as the target for all influenza A viruses because the nucleotide sequence of this gene is relatively conserved among all the influenza A viruses. The World Health Organization and the US Centers for Disease Control and Prevention (CDC) have published protocols for molecular detection of influenza A virus M gene.

However, recent studies have shown that mutations in the M gene have led to a reduced sensitivity of RT-PCR assay targeting this gene. Therefore, it is important to use alternative conserved genes as the target of RT-PCR. In this study, our aim is to evaluate two new RT-PCR assays that are based on PB2 and NS gene segment.

Description:

I. Background

• Seasonal influenza virus causes an estimated 0.3-0.6 million deaths per year. Avian influenza virus H5N1, H7N9 and H5N6 has fatality rate of over 30%. Swine influenza viruses from pigs have also infected humans.

• Molecular assays are now used routinely in the detection of influenza viruses. The M gene is often used as the target for all influenza A viruses because the nucleotide sequence of this gene is relatively conserved among all the influenza A viruses. The World Health Organization and the US Centers for Disease Control and Prevention (CDC) have published protocols for molecular detection of influenza A virus M gene.

• However, recent studies have shown that mutations in the M gene have led to a reduced sensitivity of RT-PCR assay targeting this gene. Therefore, it is important to use alternative conserved genes as the target of RT-PCR. In this study, our aim is to evaluate two new RT-PCR assays that are based on PB2 and NS gene segment

II. Study objective -To evaluate the sensitivity and specificity of 2 new RT-PCR assays

III. Overall study design

• The investigators will randomly retrieve archived nasopharyngeal and saliva specimens that were previously tested for influenza A virus using commercially available assays in our laboratory, tested for influenza A virus at the Public Health Laboratory Service Branch in Hong Kong. These specimens will be tested for influenza A virus by 4 different RT-PCR assays as listed below:

1. Our new RT-PCR assay targeting PB2 gene

2. Our new RT-PCR assay targeting NS gene

3. M gene RT-PCR published by the World Health Organization

4. M gene RT-PCR published by the US CDC

Sensitivity, specificity, positive predictive value and negative predictive value will be determined.

IV. Nucleic acid extraction and real-time reverse transcription-polymerase chain reaction (RT-PCR) for influenza A virus

• Saliva and nasopharyngeal specimens will be subjected to total nucleic acid (TNA) extraction by NucliSENS easyMAG (BioMerieux, Boxtel, Netherlands).

• Monoplex real-time RT-PCR assays for influenza A virus will be performed. The primers and probes for the M gene RT-PCR have been published by the WHO and the US CDC.

V. Sample size:

• The investigators will perform all 4 RT-PCR assays on a total of 320 specimens, including

• 80 nasopharyngeal specimens which tested positive for influenza A by commercially-available molecular assays or by testing performed at the Public Health Laboratory Services Branch in Hong Kong

• 80 nasopharyngeal specimens which tested negative for influenza A by commercially-available molecular assays or by testing performed at the Public Health Laboratory Services Branch in Hong Kong

• 80 saliva specimens which tested positive for influenza A by commercially-available molecular assays

• 80 saliva specimens which tested negative for influenza A by commercially-available molecular assays

Recruitment information / eligibility

• Status: Withdrawn
• Enrollment: 0
• Est. completion date: July 30, 2019
• Est. primary completion date: July 30, 2019
• Accepts healthy volunteers: No
• Gender: All
• Age group: N/A and older

Eligibility

Inclusion Criteria:

• Nasopharyngeal or saliva specimens of patients in Queen Mary Hospital of Hong Kong

• Tested for influenza A virus using a commercially available assay or by the Public Health Laboratory Services Branch in Hong Kong

Exclusion Criteria:

• Insufficient specimen volume

Related Conditions & MeSH terms

• Influenza A Virus
• Influenza, Human

Intervention

Diagnostic Test:
• PB2 gene RT-PCR; NS gene RT-PCR
PB2 gene RT-PCR: RT-PCR targeting the PB2 gene of influenza A virus NS gene RT-PCR: RT-PCR targeting NS gene of influenza A virus

Locations

Country	Name	City	State
Hong Kong	Queen Mary Hospital	Hong Kong

Sponsors (1)

Lead Sponsor	Collaborator
The University of Hong Kong

Country where clinical trial is conducted

Hong Kong, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	RT-PCR result	The result of RT-PCR can be positive or negative	Through study completion, an average of 2 months
Secondary	Cycle threshold value	The cycle threshold is a surrogate for viral load	Through study completion, an average of 2 months