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1.
PLoS Med ; 19(3): e1003930, 2022 03.
Article in English | MEDLINE | ID: covidwho-1793652

ABSTRACT

BACKGROUND: Low syphilis testing uptake is a major public health issue among men who have sex with men (MSM) in many low- and middle-income countries. Syphilis self-testing (SST) may complement and extend facility-based testing. We aimed to evaluate the effectiveness and costs of providing SST on increasing syphilis testing uptake among MSM in China. METHODS AND FINDINGS: An open-label, parallel 3-arm randomized controlled trial (RCT) was conducted between January 7, 2020 and July 17, 2020. Men who were at least 18 years of age, had condomless anal sex with men in the past year, reported not testing for syphilis in the last 6 months, and had a stable residence with mailing addresses were recruited from 124 cities in 26 Chinese provinces. Using block randomization with blocks of size 12, enrolled participants were randomly assigned (1:1:1) into 3 arms: standard of care arm, standard SST arm, and lottery incentivized SST arm (1 in 10 chance to win US$15 if they had a syphilis test). The primary outcome was the proportion of participants who tested for syphilis during the trial period and confirmed with photo verification and between arm comparisons were estimated with risk differences (RDs). Analyses were performed on a modified intention-to-treat basis: Participants were included in the complete case analysis if they had initiated at least 1 follow-up survey. The Syphilis/HIV Duo rapid test kit was used. A total of 451 men were enrolled. In total, 136 (90·7%, 136/150) in the standard of care arm, 142 (94·0%, 142/151) in the standard of SST arm, and 137 (91·3%, 137/150) in the lottery incentivized SST arm were included in the final analysis. The proportion of men who had at least 1 syphilis test during the trial period was 63.4% (95% confidence interval [CI]: 55.5% to 71.3%, p = 0.001) in the standard SST arm, 65.7% (95% CI: 57.7% to 73.6%, p = 0.0002) in the lottery incentivized SST arm, and 14.7% (95% CI: 8.8% to 20.7%, p < 0.001) in the standard of care arm. The estimated RD between the standard SST and standard of care arm was 48.7% (95% CI: 37.8% to 58.4%, p < 0.001). The majority (78.5%, 95% CI: 72.7% to 84.4%, p < 0.001) of syphilis self-testers reported never testing for syphilis. The cost per person tested was US$26.55 for standard SST, US$28.09 for the lottery incentivized SST, and US$66.19 for the standard of care. No study-related adverse events were reported during the study duration. Limitation was that the impact of the Coronavirus Disease 2019 (COVID-19) restrictions may have accentuated demand for decentralized testing. CONCLUSIONS: Compared to standard of care, providing SST significantly increased the proportion of MSM testing for syphilis in China and was cheaper (per person tested). TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR1900022409.


Subject(s)
HIV Infections/diagnosis , Homosexuality, Male , Patient Participation/methods , Self-Testing , Syphilis/diagnosis , Adolescent , Adult , COVID-19/epidemiology , China/epidemiology , Follow-Up Studies , HIV Infections/prevention & control , Health Services Accessibility/organization & administration , Homosexuality, Male/statistics & numerical data , Humans , Immunoassay/methods , Male , Mass Screening/economics , Mass Screening/methods , Mass Screening/organization & administration , Middle Aged , Motivation , Pandemics , Reagent Kits, Diagnostic/economics , Reagent Kits, Diagnostic/supply & distribution , SARS-CoV-2 , Sexual and Gender Minorities/statistics & numerical data , Syphilis/epidemiology , Syphilis/prevention & control , Young Adult
2.
Klin Lab Diagn ; 65(11): 683-687, 2020 Dec 04.
Article in English | MEDLINE | ID: covidwho-1780382

ABSTRACT

A new original Russian test kit for the detection of IgG-antibodies to the causative agent of COVID-19 - coronavirus SARS-CoV-2 by the method of enzyme-linked immunosorbent assay (ELISA) on a solid-phase «ELISA-SARS-CoV-2-AT-G¼ has been developed. In comparative tests with similar test systems «Vitrotest® SARS-CoV-2 IgG¼ (Vitrotest, Ukraine) and «Anti-SARS-Cov-2 ELISA (IgG)¼ (EUROIMMUN AG, Germany) high diagnostic efficiency of the new test system was shown.


Subject(s)
Antibodies, Viral/analysis , COVID-19 Serological Testing , COVID-19/diagnosis , Enzyme-Linked Immunosorbent Assay , Immunoglobulin G/analysis , Clinical Laboratory Techniques , Humans , Plasma , Reagent Kits, Diagnostic
3.
Viruses ; 12(6)2020 05 26.
Article in English | MEDLINE | ID: covidwho-1726015

ABSTRACT

The recent outbreak of the Coronavirus disease 2019 (COVID-19) has quickly spread worldwide since its discovery in Wuhan city, China in December 2019. A comprehensive strategy, including surveillance, diagnostics, research, clinical treatment, and development of vaccines, is urgently needed to win the battle against COVID-19. The past three unprecedented outbreaks of emerging human coronavirus infections at the beginning of the 21st century have highlighted the importance of readily available, accurate, and rapid diagnostic technologies to contain emerging and re-emerging pandemics. Real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) based assays performed on respiratory specimens remain the gold standard for COVID-19 diagnostics. However, point-of-care technologies and serologic immunoassays are rapidly emerging with high sensitivity and specificity as well. Even though excellent techniques are available for the diagnosis of symptomatic patients with COVID-19 in well-equipped laboratories; critical gaps still remain in screening asymptomatic people who are in the incubation phase of the virus, as well as in the accurate determination of live viral shedding during convalescence to inform decisions for ending isolation. This review article aims to discuss the currently available laboratory methods and surveillance technologies available for the detection of COVID-19, their performance characteristics and highlight the gaps in current diagnostic capacity, and finally, propose potential solutions. We also summarize the specifications of the majority of the available commercial kits (PCR, EIA, and POC) for laboratory diagnosis of COVID-19.


Subject(s)
Clinical Laboratory Techniques , Coronavirus Infections/diagnosis , Pneumonia, Viral/diagnosis , Asymptomatic Infections , Betacoronavirus , COVID-19 , COVID-19 Testing , COVID-19 Vaccines , Humans , Immunoenzyme Techniques , Neutralization Tests , Nucleic Acid Amplification Techniques , Pandemics , Point-of-Care Testing , Reagent Kits, Diagnostic/standards , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2 , Sensitivity and Specificity , Serologic Tests , Tomography, X-Ray Computed , Virus Shedding
4.
Bioanalysis ; 14(6): 325-340, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1726396

ABSTRACT

Background: With the spread of COVID-19, anti-SARS-CoV-2 antibody tests have been utilized. Herein we evaluated the analytical performance of anti-SARS-CoV-2 antibody test kits using a new reference standard prepared from COVID-19 patient sera. Methods: Fifty-seven kits in total (16 immunochromatography types, 11 ELISA types and 30 types for automated analyzers) were examined. By measuring serially diluted reference standards, the maximum dilution factor showing a positive result and its precision were investigated. Results: The measured cut-off titers varied largely depending on the antibody kit; however, the variability was small, with the titers obtained by each kit being within twofold in most cases. Conclusion: The current results suggest that a suitable kit should be selected depending on the intended purpose.


Subject(s)
COVID-19 Serological Testing/methods , Reagent Kits, Diagnostic , Antibodies, Viral/blood , Automation, Laboratory , COVID-19 Serological Testing/instrumentation , COVID-19 Serological Testing/standards , Enzyme-Linked Immunosorbent Assay/instrumentation , Enzyme-Linked Immunosorbent Assay/methods , Humans , Immunoglobulin G/blood , Japan , SARS-CoV-2/immunology
5.
Bioanalysis ; 14(6): 317-324, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1704052

ABSTRACT

The COVID-19 pandemic continues to spread all over the world. In the process of emergency use authorization, the Center for Medical Device Evaluation of the China National Medical Products Administration issued 'Key Points of Technical Review for the Registration of SARS-CoV-2 Antigen/Antibody Detection Reagents' as the guidance of registration of antigen and antibody test reagents for the industry. In this document, clinical evaluation requirements of antigen detection reagents are elaborated. Based on the Key Points document and the authors' review practice, this article explains the evaluation methods and requirements of clinical performance of SARS-CoV-2 antigen-detecting rapid diagnostic tests, then analyzes the application scenarios and intended use of antigen detection reagents.


Subject(s)
COVID-19 Serological Testing/methods , Specimen Handling/methods , Antigens, Viral , COVID-19 Nucleic Acid Testing , China , Clinical Trials as Topic , Humans , Indicators and Reagents , Reagent Kits, Diagnostic , SARS-CoV-2/immunology
6.
Microbiol Spectr ; 10(1): e0228921, 2022 02 23.
Article in English | MEDLINE | ID: covidwho-1702730

ABSTRACT

In March 2020, the Rare and Imported Pathogens Laboratory at the UK Health Security Agency (UKHSA) (formerly Public Health England [PHE]) Porton Down, was tasked by the Department of Health and Social Care with setting up a national surveillance laboratory facility to study SARS-CoV-2 antibody responses and population-level sero-surveillance in response to the growing SARS-CoV-2 outbreak. In the following 12 months, the laboratory tested more than 160,000 samples, facilitating a wide range of research and informing UKHSA, DHSC, and UK government policy. Here we describe the implementation and use of the Euroimmun anti-SARS-CoV-2 IgG assay and provide an extended evaluation of its performance. We present a markedly improved overall sensitivity of 91.39% (≥14 days 92.74%, ≥21 days 93.59%) compared to our small-scale early study, and a specificity of 98.56%. In addition, we detail extended characteristics of the Euroimmun assay: intra- and interassay precision, correlation to neutralization, and assay linearity. IMPORTANCE Serology assays have been useful in determining those with previous SARS-CoV-2 infection in a wide range of research and serosurveillance projects. However, assays vary in their sensitivity at detecting SARS-CoV-2 antibodies. Here, we detail an extended evaluation and characterization of the Euroimmun anti-SARS-CoV-2 IgG assay, one that has been widely used within the United Kingdom on over 160,000 samples to date.


Subject(s)
Antibodies, Viral/blood , COVID-19 Serological Testing/methods , COVID-19/blood , Immunoglobulin G/blood , SARS-CoV-2/immunology , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/virology , Humans , Public Health , Reagent Kits, Diagnostic , SARS-CoV-2/genetics , Sensitivity and Specificity , United Kingdom/epidemiology
8.
Int Urol Nephrol ; 54(3): 493-498, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1653676

ABSTRACT

The COVID-19 pandemic and subsequent lockdown had a substantial impact on normal research operations. Researchers needed to adapt their methods to engage at-home participants. One method is crowdsourcing, in which researchers use social media to recruit participants, gather data, and collect samples. We utilized this method to develop a diagnostic test for Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS). Participants were recruited via posts on popular social-media platforms, and enrolled via a website. Participants received and returned a mail kit containing bladder symptom surveys and a urine sample cup containing room-temperature preservative. Using this method, we collected 1254 IC/BPS and control samples in 3 months from all 50 United States. Our data demonstrate that crowdsourcing is a viable alternative to traditional research, with the ability to reach a broad patient population rapidly. Crowdsourcing is a powerful tool for at-home participation in research, particularly during the lockdown caused by the COVID-19 pandemic.


Subject(s)
Biomedical Research , COVID-19 , Crowdsourcing/methods , Cystitis, Interstitial , Patient Participation , Urinalysis , Biomedical Research/organization & administration , Biomedical Research/trends , COVID-19/epidemiology , COVID-19/prevention & control , Communicable Disease Control , Cystitis, Interstitial/diagnosis , Cystitis, Interstitial/epidemiology , Diagnostic Techniques and Procedures/trends , Female , Humans , Male , Middle Aged , Patient Participation/methods , Patient Participation/statistics & numerical data , Patient Selection , Reagent Kits, Diagnostic/supply & distribution , Research Design , SARS-CoV-2 , Social Media , Specimen Handling/methods , United States/epidemiology , Urinalysis/instrumentation , Urinalysis/methods
9.
Anal Bioanal Chem ; 414(5): 1773-1785, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1653430

ABSTRACT

Nucleic acid tests to detect the SARS-CoV-2 virus have been performed worldwide since the beginning of the COVID-19 pandemic. For the quality assessment of testing laboratories and the performance evaluation of molecular diagnosis products, reference materials (RMs) are required. In this work, we report the production of a lentiviral SARS-CoV-2 RM containing approximately 12 kilobases of its genome including common diagnostics targets such as RdRp, N, E, and S genes. The RM was measured with multiple assays using two different digital PCR platforms. To measure the homogeneity and stability of the lentiviral SARS-CoV-2 RM, reverse transcription droplet digital PCR (RT-ddPCR) was used with in-house duplex assays. The copy number concentration of each target gene in the extracted RNA solution was then converted to that of the RM solution. Their copy number values are measured to be from 1.5 × 105 to 2.0 × 105 copies/mL. The RM has a between-bottle homogeneity of 4.80-8.23% and is stable at 4 °C for 1 week and at -70 °C for 6 months. The lentiviral SARS-CoV-2 RM closely mimics real samples that undergo identical pre-analytical processes for SARS-CoV-2 molecular testing. By offering accurate reference values for the absolute copy number of viral target genes, the developed RM can be used to improve the reliability of SARS-CoV-2 molecular testing.


Subject(s)
COVID-19 Nucleic Acid Testing/methods , COVID-19/diagnosis , Genome, Viral , RNA, Viral/genetics , Reagent Kits, Diagnostic/standards , SARS-CoV-2/genetics , COVID-19/virology , COVID-19 Nucleic Acid Testing/standards , Coronavirus Envelope Proteins/genetics , Coronavirus Envelope Proteins/metabolism , Coronavirus Nucleocapsid Proteins/genetics , Coronavirus Nucleocapsid Proteins/metabolism , Coronavirus RNA-Dependent RNA Polymerase/genetics , Coronavirus RNA-Dependent RNA Polymerase/metabolism , Gene Dosage , Gene Expression , Humans , Jurkat Cells , Lentivirus/genetics , Lentivirus/metabolism , Phosphoproteins/genetics , Phosphoproteins/metabolism , RNA, Viral/metabolism , RNA, Viral/standards , Reagent Kits, Diagnostic/supply & distribution , Reference Standards , Reproducibility of Results , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Viral Genome Packaging
11.
PLoS One ; 17(1): e0262733, 2022.
Article in English | MEDLINE | ID: covidwho-1643277

ABSTRACT

This study aims at establishing specimens pooling approach for the detection of SARS-CoV-2 using the RT-PCR BGI and Sansure-Biotech kits used in Gabon. To validate this approach, 14 positive samples, stored at -20°C for three to five weeks were analyzed individually (as gold standard) and in pools of five, eight and ten in the same plate. We created 14 pools of 5, 8 and 10 samples using 40 µL from each of the selected positive samples mixed with 4, 7 and 9 confirmed negative counterparts in a total volume of 200 µL, 320 µL and 400 µL for the pools of 5, 8 and 10 respectively. Both individual and pooled samples testing was conducted according to the BGI and Sansure-Biotech RT-PCR protocols used at the Professor Daniel Gahouma Laboratory (PDGL). Furthermore, the pooling method was also tested by comparing results of 470 unselected samples tested in 94 pools and individually. Results of our experiment showed that using a BGI single positive sample with cycle threshold (Ct) value of 28.42, confirmed by individual testing, detection occurred in all the pools. On the contrary samples with Ct >31 were not detected in pools of 10 and for these samples (Ct value as high as 37.17) their detection was possible in pool of 8. Regarding the Sansure-Biotech kit, positive samples were detected in all the pool sizes tested, irrespective of their Ct values. The specificity of the pooling method was 100% for the BGI and Sansure-Biotech RT-PCR assays. The present study found an increase in the Ct values with pool size for the BGI and Sansure-Biotech assays. This trend was statistically significant (Pearson's r = 0.978; p = 0,022) using the BGI method where the mean Ct values were 24.04±1.1, 26.74±1.3, 27.91±1.1 and 28.32±1.1 for the individual, pool of 5, 8 and 10 respectively. The testing of the 470 samples showed that one of the 94 pools had a positive test similar to the individual test using the BGI and Sansure-Biotech kits. The saving of time and economizing test reagents by using the pooling method were demonstrated in this study. Ultimately, the pooling method could be used for the diagnosis of SARS-CoV-2 without modifying the accuracy of results in Gabon. We recommend a maximum pool size of 8 for the BGI kit. For the Sansure-Biotech kit, a maximum pool size of 10 can be used without affecting its accuracy compared to the individual testing.


Subject(s)
COVID-19 Nucleic Acid Testing/standards , COVID-19/diagnosis , RNA, Viral/genetics , SARS-CoV-2/genetics , Specimen Handling/methods , COVID-19/epidemiology , Gabon/epidemiology , Health Services , Humans , Reagent Kits, Diagnostic/standards , SARS-CoV-2/classification , Sensitivity and Specificity
13.
JAMA Otolaryngol Head Neck Surg ; 148(3): 252-258, 2022 03 01.
Article in English | MEDLINE | ID: covidwho-1620083

ABSTRACT

Importance: Current tools for diagnosis of olfactory dysfunction (OD) are costly, time-consuming, and often require clinician administration. Objective: To develop and validate a simple screening assessment for OD using common household items. Design, Setting, and Participants: This fully virtual diagnostic study included adults with self-reported OD from any cause throughout the US. Data were collected from December 2020 to April 2021 and analyzed from May 2021 to July 2021. Main Outcomes and Measures: Participants with self-reported olfactory dysfunction took a survey assessing smell perception of 45 household items and completed the Clinical Global Impression-Severity (CGI-S) smell questionnaire, the University of Pennsylvania Smell Identification Test (UPSIT), and the 36-item Short Form Survey (SF-36). Psychometric and clinimetric analyses were used to consolidate 45 household items into 2 short Novel Anosmia Screening at Leisure (NASAL) assessments, NASAL-7 (range, 0-14; lower score indicating greater anosmia) and NASAL-3 (range, 0-6; lower score indicating greater anosmia). Results: A total of 115 participants were included in the study, with a median (range) age of 42 (19-70) years, 92 (80%) women, and 97 (84%) White individuals. There was a moderate correlation between the UPSIT and NASAL-7 scores and NASAL-3 scores (NASAL-7: ρ = 0.484; NASAL-3: ρ = 0.404). Both NASAL-7 and NASAL-3 had moderate accuracy in identifying participants with anosmia as defined by UPSIT (NASAL-7 area under the receiver operating curve [AUC], 0.706; 95% CI, 0.551-0.862; NASAL-3 AUC, 0.658; 95% CI, 0.503-0.814). Scoring 7 or less on the NASAL-7 had 70% (95% CI, 48%-86%) sensitivity and 53% (95% CI, 43%-63%) specificity in discriminating participants with anosmia from participants without. Scoring 2 or less on the NASAL-3 had 57% (95% CI, 36%-76%) sensitivity and 78% (95% CI, 69%-85%) specificity in discriminating participants with anosmia from participants without. There was moderate agreement between UPSIT-defined OD categories and those defined by NASAL-7 (weighted κ = 0.496; 95% CI, 0.343-0.649) and those defined by NASAL-3 (weighted κ = 0.365; 95% CI, 0.187-0.543). The agreement with self-reported severity of olfactory dysfunction as measured by CGI-S and the NASAL-7 and NASAL-3 was moderate, with a weighted κ of 0.590 (95% CI, 0.474-0.707) for the NASAL-7 and 0.597 (95% CI, 0.481-0.712) for the NASAL-3. Conclusion and Relevance: The findings of this diagnostic study suggest that NASAL-7 and NASAL-3, inexpensive and brief patient-reported assessments, can be used to identify individuals with OD. As the burden of COVID-19-associated OD increases, these assessments may prove beneficial as screening and diagnostic tools. Future work will explore whether the NASAL assessments are sensitive to change and how much of a change is clinically important.


Subject(s)
COVID-19/complications , Olfaction Disorders/diagnosis , Olfaction Disorders/virology , Adult , Aged , Female , Humans , Male , Middle Aged , Pandemics , Reagent Kits, Diagnostic , SARS-CoV-2 , Surveys and Questionnaires , Young Adult
14.
J Clin Lab Anal ; 36(2): e24242, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1616016

ABSTRACT

BACKGROUND: Currently, SARS-CoV-2 RNA detection using real-time reverse-transcription PCR (rRT-PCR) is the standard diagnostic test for COVID-19 infection. Various rRT-PCR assays are currently used worldwide, targeting different genes of the SARS-CoV-2. Here, we compared the analytical sensitivity and clinical performance (sensitivity and specificity) of Allplex SARS-CoV-2/FluA/FluB/RSV assay (Seegene), Standard M nCoV real-time detection kit (SD Biosensor), and U-TOP COVID-19 detection kit (Seasun Biomaterials) for SARS-CoV-2 detection. METHODS: Two hundred and forty-nine nasopharyngeal swab samples were evaluated to compare the clinical performance of the rRT-PCR assays. For the analytical performance evaluation, two RNA controls with known viral loads-SARS-CoV-2 RNA control and SARS-COV-2 B.1.351 RNA control-were used to investigate the potential impact of SARS-CoV-2 variants, particularly the B.1.351 lineage. RESULTS: Limits of detection ranged from 650 to 1300 copies/ml for rRT-PCR assays, and the mean differences in cycle threshold (Ct ) values of the two RNA controls were within 1.0 for each target in the rRT-PCR assays (0.05-0.73), without any prominent Ct value shift or dropouts in the SARS-COV-2 B.1.351 RNA control. Using the consensus criterion as the reference standard, 89 samples were positive, whereas 160 were negative. The overall clinical performance of rRT-PCR assays was comparable (sensitivity 98.88%-100%; specificity 99.38%-100%), whereas the sensitivities of each target gene were more variable. CONCLUSIONS: The three rRT-PCR assays showed comparable analytical sensitivity and clinical performance. The analytical and clinical sensitivities of each target gene were influenced more by the primer and probe design than the target gene itself.


Subject(s)
COVID-19/diagnosis , Molecular Diagnostic Techniques , Reagent Kits, Diagnostic/virology , Real-Time Polymerase Chain Reaction , SARS-CoV-2/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Child , Female , Humans , Male , Middle Aged , Molecular Diagnostic Techniques/methods , Molecular Diagnostic Techniques/standards , Nasopharynx/virology , Real-Time Polymerase Chain Reaction/methods , Real-Time Polymerase Chain Reaction/standards , SARS-CoV-2/isolation & purification , Sensitivity and Specificity , Viral Load , Young Adult
15.
Viruses ; 14(1)2021 12 23.
Article in English | MEDLINE | ID: covidwho-1580413

ABSTRACT

Diagnostics of the coronavirus disease 2019 (COVID-19) using molecular techniques from the collected respiratory swab specimens requires well-equipped laboratory and qualified personnel, also it needs several hours of waiting for results and is expensive. Antigen tests appear to be faster and cheaper but their sensitivity and specificity are debatable. The aim of this study was to compare a selected antigen test with quantitative polymerase chain reaction (qPCR) tests results. Nasopharyngeal swabs were collected from 192 patients with COVID-19 symptoms. All samples were tested using Vitassay qPCR SARS-CoV-2 kit and the Humasis COVID-19 Ag Test (MedSun) antigen immunochromatographic test simultaneously. Ultimately, 189 samples were tested; 3 samples were excluded due to errors in taking swabs. The qPCR and antigen test results were as follows: 47 positive and 142 negative, and 45 positive and 144 negative, respectively. Calculated sensitivity of 91.5% and specificity of 98.6% for the antigen test shows differences which are not statistically significant in comparison to qPCR. Our study showed that effectiveness of the antigen tests in rapid laboratory diagnostics is high enough to be an alternative and support for nucleic acid amplification tests (NAAT) in the virus replication phase in the course of COVID-19.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , SARS-CoV-2/isolation & purification , Antigens, Viral/immunology , Humans , Nasopharynx/virology , RNA, Viral/genetics , Reagent Kits, Diagnostic , Real-Time Polymerase Chain Reaction , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Sensitivity and Specificity
16.
J Clin Lab Anal ; 36(2): e24203, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1589068

ABSTRACT

BACKGROUND: Globally, real-time reverse transcription-polymerase chain reaction (rRT-PCR) is the reference detection technique for SARS-CoV-2, which is expensive, time consuming, and requires trained laboratory personnel. Thus, a cost-effective, rapid antigen test is urgently needed. This study evaluated the performance of the rapid antigen tests (RATs) for SARS-CoV-2 compared with rRT-PCR, considering different influencing factors. METHODS: We enrolled a total of 214 symptomatic individuals with known COVID-19 status using rRT-PCR. We collected and tested paired nasopharyngeal (NP) and nasal swab (NS) specimens (collected from same individual) using rRT-PCR and RATs (InTec and SD Biosensor). We assessed the performance of RATs considering specimen types, viral load, the onset of symptoms, and presenting symptoms. RESULTS: We included 214 paired specimens (112 NP and 100 NS SARS-CoV-2 rRT-PCR positive) to the analysis. For NP specimens, the average sensitivity, specificity, and accuracy of the RATs were 87.5%, 98.6%, and 92.8%, respectively, when compared with rRT-PCR. While for NS, the overall kit performance was slightly lower than that of NP (sensitivity 79.0%, specificity 96.1%, and accuracy 88.3%). We observed a progressive decline in the performance of RATs with increased Ct values (decreased viral load). Moreover, the RAT sensitivity using NP specimens decreased over the time of the onset of symptoms. CONCLUSION: The RATs showed strong performance under field conditions and fulfilled the minimum performance limit for rapid antigen detection kits recommended by World Health Organization. The best performance of the RATs can be achieved within the first week of the onset of symptoms with high viral load.


Subject(s)
Antigens, Viral/analysis , COVID-19 Serological Testing , COVID-19/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19 Serological Testing/methods , COVID-19 Serological Testing/standards , COVID-19 Serological Testing/statistics & numerical data , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Nasopharynx/virology , Reagent Kits, Diagnostic/virology , SARS-CoV-2/isolation & purification , Sensitivity and Specificity , Time Factors , Viral Load , Young Adult
17.
Lab Med ; 52(6): e147-e153, 2021 Nov 02.
Article in English | MEDLINE | ID: covidwho-1574316

ABSTRACT

OBJECTIVE: In this study, the performance of 2 commercially available SARS-CoV-2 antibody assays is evaluated. METHODS: The Siemens SARS-CoV-2 Total (COV2T) and IgG (COV2G) antibody tests were evaluated on a Siemens Atellica IM1300 analyzer. Imprecision was assessed with the CLSI EP15 protocol using positive controls. Ninety control group specimens were analyzed for specificity, and 175 specimens from 58 patients with polymerase chain reaction-confirmed SARS-CoV-2 were measured for the sensitivity and kinetics of the antibody response. RESULTS: Within-run and total imprecision were acceptable for both assays. Both tests showed a specificity of 100%. Sensitivity earlier in the disease state was greater for the COV2T assay than for the COV2G assay, but sensitivity >14 days after onset of symptoms approached 100% for both. For all patients, antibody titers remained above the seroconversion cutoff for all follow-up specimens. CONCLUSION: This study shows acceptable performance for both the Siemens COV2T and COV2G test, although seroconversion occurs earlier with the COV2T test.


Subject(s)
Antibodies, Viral/blood , COVID-19 Serological Testing/standards , COVID-19/diagnosis , Immunoglobulin G/blood , SARS-CoV-2/immunology , Aged , Aged, 80 and over , Automation, Laboratory , COVID-19/blood , COVID-19/immunology , COVID-19/virology , COVID-19 Serological Testing/methods , Enzyme-Linked Immunosorbent Assay/methods , Female , Humans , Male , Reagent Kits, Diagnostic , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction/methods , Sensitivity and Specificity
18.
J Korean Med Sci ; 36(48): e328, 2021 Dec 13.
Article in English | MEDLINE | ID: covidwho-1572278

ABSTRACT

BACKGROUND: In the coronavirus disease 2019 (COVID-19) pandemic era, the simultaneous detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza virus (Flu), and respiratory syncytial virus (RSV) is important in the rapid differential diagnosis in patients with respiratory symptoms. Three multiplex real-time reverse transcription polymerase chain reaction (rRT-PCR) assays have been recently developed commercially in Korea: PowerChek™ SARS-CoV-2, Influenza A&B Multiplex Real-time PCR Kit (PowerChek; KogeneBiotech); STANDARD™ M Flu/SARS-CoV-2 Real-time Detection Kit (STANDARD M; SD BioSensor); and Allplex™ SARS-CoV-2/FluA/FluB/RSV Assay (Allplex; Seegene). We evaluated the analytical and clinical performances of these kits. METHODS: A limit of detection tests were performed and cross-reactivity analysis was executed using clinical respiratory samples. Ninety-seven SARS-CoV-2-positive, 201 SARS-CoV-2-negative, 71 influenza A-positive, 50 influenza B-positive, 78 RSV-positive, and 207 other respiratory virus-positive nasopharyngeal swabs were tested using the three assays. The AdvanSure™ respiratory viruses rRT-PCR assay (AdvanSure; LG Life Sciences) was used as a comparator assay for RSV. RESULTS: Except in influenza B, in SARS-CoV-2 and influenza A, there were no significant differences in detecting specific genes of the viruses among the three assays. All three kits did not cross-react with common respiratory viruses. All three kits had greater than 92% positive percent agreement and negative percent agreement and ≥ 0.95 kappa value in the detection of SARS-CoV-2 and flu A/B. Allplex detected RSV more sensitively than AdvanSure. CONCLUSION: The overall performance of three multiplex rRT-PCR assays for the concurrent detection of SARS-CoV-2, influenza A/B, and RSV was comparable. These kits will promote prompt differential diagnosis of COVID-19, influenza, and RSV infection in the COVID-19 pandemic era.


Subject(s)
COVID-19/diagnosis , Influenza, Human/diagnosis , Multiplex Polymerase Chain Reaction/methods , Nasopharynx/virology , RNA, Viral/analysis , Respiratory Syncytial Virus Infections/diagnosis , COVID-19/virology , Cross Reactions , Humans , Influenza A virus/genetics , Influenza A virus/isolation & purification , Influenza B virus/genetics , Influenza B virus/isolation & purification , Influenza, Human/virology , Limit of Detection , Nucleocapsid Proteins/genetics , Polyproteins/genetics , RNA, Viral/metabolism , Reagent Kits, Diagnostic , Republic of Korea , Respiratory Syncytial Virus Infections/virology , Respiratory Syncytial Virus, Human/genetics , Respiratory Syncytial Virus, Human/isolation & purification , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Viral Matrix Proteins/genetics , Viral Proteins/genetics
19.
PLoS One ; 16(12): e0260732, 2021.
Article in English | MEDLINE | ID: covidwho-1571987

ABSTRACT

The Loopamp SARS-CoV-2 Detection Kit is used for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Loop-mediated isothermal amplification (LAMP) is based on a measurement principle that can be used with a relatively simple device. Detection using this kit requires viral RNA extraction from samples with the QIAGEN QIAamp Viral Mini Kit (QIAGEN extraction) or the Loopamp Viral RNA Extraction Kit (Eiken extraction), which are recommended by the manufacturer. However, the efficacy of LAMP-based SARS-CoV-2 detection using these extraction methods has not been compared. In this study, we aimed to compare the results of genome extraction and detection from nasopharyngeal swab samples using the QIAGEN and Eiken extraction kits. The present study involved patients who presented to the Rinku General Medical Center with suspected COVID-19 (25 positive and 26 negative cases). A comparison of the results obtained using each extraction method with those obtained via PCR showed that the positive, negative, and overall concordance rates between QIAGEN extraction and PCR were 96.0% (24/25 samples), 100% (26/26), and 98.0% (50/51; κ = 0.96, 95% CI = 0.69-1.00), respectively. Results with Eiken extraction were also favorable, with positive, negative, and overall concordance rates of 88.0% (22/25), 100% (26/26), and 94.1% (48/51; κ = 0.88, 95% CI = 0.61-1.00), respectively. Favorable results were obtained using both QIAGEN and Eiken extraction kits. Since Eiken extraction can be completed in a few minutes, it enables prompt and reliable testing for SARS-CoV-2 detection.


Subject(s)
COVID-19/diagnosis , Molecular Diagnostic Techniques/methods , Nasopharynx/virology , Nucleic Acid Amplification Techniques/methods , RNA, Viral/genetics , SARS-CoV-2/isolation & purification , Humans , Prospective Studies , Reagent Kits, Diagnostic , SARS-CoV-2/genetics , Sensitivity and Specificity
20.
Clin Chim Acta ; 525: 46-53, 2022 Jan 15.
Article in English | MEDLINE | ID: covidwho-1559179

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has caused a global pandemic beginning in 2020, can be detected by reverse-transcription polymerase chain reaction (RT-PCR). However, owing to the urgent need for a large number of detection kits, the time spent researching and developing these kits has been shortened during the pandemic, and the kits that are being used commercially have not undergone full and independent evaluation. To ensure the accuracy of SARS-CoV-2 test results, performance verification of commercial Real-Time quantitative PCR (RT-qPCR) kits is required. METHODS: The performance of five commercial RT-qPCR diagnostic kits for SARS-CoV-2 used in China was evaluated using a coronavirus disease 2019 (COVID-19) RNA liquid performance verification reference product-manufactured by Guangzhou Bondson (BDS) Biotechnology Co., Ltd.,Guangzhou, China-that uses droplet digital RT-PCR technology combined with fluorescence quantitative PCR. The five kits of Novel Coronavirus 2019-nCoV nucleic acid detection kit (RT-qPCR method) evaluated were Da An (Da An Gene Co., Ltd. of Sun Yat-sen University), Liferiver (Shanghai ZJ Bio-Tech Co., Ltd.), Kinghawk (Beijing Kinghawk Pharmaceutical Co., Ltd.), eDiagnosis (Wuhan Easy Diagnosis Biomedicine Co., Ltd.), and Maccura (Maccura Biotechnology Co., Ltd.). Performance verification criteria included the coincidence rate, limit of detection (LoD), cross-reactivity, precision, and anti-interference. Finally, through the BDS performance verification reference product kit, clinical samples are used to verify its clinical diagnostic efficacy. RESULTS: The coincidence rate was 100% for all kits except for Kinghawk, which was 95%. The LoD for Da An, eDiagnosis and Maccura was 250copies/mL, and it was 1000 copies/ml for Liferiver. Kinghawk was not able to detect its advertised LoD of 500 copies/ml. The cross-reactivity test results were all negative. Moreover, all kits had a coefficient of variation less than 5%; however, Liferiver showed the best precision. Da An, Liferiver, and eDiagnosis showed higher sensitivity to the nucleocapsid (N) gene than they did to the open reading frame (ORF) 1ab genes. Anti-interference results for all five kits were positive. The results of clinical diagnostic efficacy were that the specificity of the four kits was 1.000 (0.877-1.000), the sensitivity of Da An was 1.000 (0.850-1.000), Liferiver was 0.964 (0.798-0.998), Maccura was 0.893 (0.706-0.972), and eDiagnosis was 0.857 (0.664-0.953). CONCLUSIONS: All commercial RT-qPCR diagnostic kits for SARS-CoV-2 passed the BDS performance verification, except for Kinghawk (batch No:20200608113) which failed to detect the LoD of 500 copies/mL. Da An and Liferiver have excellent clinical diagnostic specificity and sensitivity. This study can provide guidance for the selection or optimization of RT-qPCR diagnostic test kits for SARS-CoV-2.


Subject(s)
COVID-19 , SARS-CoV-2 , China , Humans , Pandemics , RNA, Viral/genetics , Reagent Kits, Diagnostic , Real-Time Polymerase Chain Reaction , Sensitivity and Specificity
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