scholarly journals Development, deployment and in-field demonstration of mobile coronavirus SARS-CoV-2 Nucleic acid amplification test

2021 ◽  
Vol 70 (4) ◽  
Author(s):  
Teagan F. Paton ◽  
Ian Marr ◽  
Zoe O’Keefe ◽  
Timothy J. J. Inglis

Introduction. The evolving SARS-CoV-2 coronavirus pandemic presents a series of challenges to clinical diagnostic services. Many proprietary PCR platforms deployed outside centralised laboratories have limited capacity to upscale when public health demands increase. We set out to develop and validate an open-platform mobile laboratory for remote area COVID-19 diagnosis, with a subsequent field trial. Gap Statement. In regional Western Australia, molecular diagnostic support is limited to near point-of-care devices. We therefore aimed to demonstrate open-platform capability in a rapidly deployable format within the context of the COVID-19 pandemic. Methodology. We compared, selected and validated components of a SARS-CoV-2 RT-PCR assay in order to establish a portable molecular diagnostics laboratory. The optimal combination of PCR assay equipment, reagents and consumables required for operation to national standards in regional laboratories was identified. This comprised RNA extraction and purification (QuickGene-480, Kurabo, Japan), a duplex RT-PCR assay (Logix Smart COVID-19, Co-Diagnostics, USA), a Myra liquid handling robot (Biomolecular Systems, Australia) and a magnetic induction thermal cycler (MIC, Biomolecular Systems). Results The 95 and 99% limits of detection were 1.01 copies μl−1 (5.05 copies per reaction) and 2.80 copies μl−1 (14.00 copies per reaction) respectively. The Co-Diagnostics assay amplified both SARS-CoV-1 and −2 RNA but showed no other cross reactivity. Qualitative results aligned with the reference laboratory SARS-CoV-2 assay (sensitivity 100% [95 % CI 96.48–100%], specificity 100% [95% CI 96.52–100%]). In field trials, the laboratory was operational within an hour of arrival on-site, can process up to 36 samples simultaneously, produces results in two and a half hours from specimen reception, and performed well during six consecutive runs during a 1 week deployment. Conclusion. Our mobile laboratory enables an adaptive response to increased test demand, and unlike many proprietary point-of-care PCR systems, rapid substitution with an alternative assay if gene targets change or reagent supply chains fail. We envisage operation of this RT-PCR assay as a standby capability to meet varying regional test demands under public health emergency operations guidance.

2021 ◽  
Author(s):  
Jessica Caffry ◽  
Matthew Selby ◽  
Katie Barr ◽  
George Morgan ◽  
David McGurk ◽  
...  

Background: Accurate, affordable, and rapid point-of-care (PoC) diagnostics are critical to the global control and management of the COVID-19 pandemic. The current standard for accurate diagnosis of SARS-CoV-2 is laboratory-based reverse transcription polymerase chain reaction (RT-PCR). Here, we report a preliminary prospective performance evaluation of the QuantuMDx Q-POC SARS CoV-2 RT-PCR assay. Methods: Between November 2020 and March 2021, we obtained 49 longitudinal nose and throat swabs from 29 individuals hospitalised with RT-PCR confirmed COVID-19 at St Georges' NHS Foundation Trust, London (UK). In addition, we obtained 101 mid nasal swabs from healthy volunteers in June 2021. We then used these samples to evaluate the Q-POC SARS-CoV-2 RT-PCR assay. The primary analysis was to compare the sensitivity and specificity of the Q-POC test against a reference laboratory-based RT-PCR assay. Results: The overall sensitivity of the Q-POC test compared with the reference test was 96.88% (83.78%- 99.92% CI) for a cycle threshold (Ct) cut-off value for the reference test of 35 and 80.00% (64.35% to 90.95% CI) without altering the reference test's Ct cut-off value of 40. Conclusions: The Q-POC test is a sensitive, specific and rapid point-of-care test for SARS-CoV-2 at a reference Ct cut-off value of 35. The Q-POC test provides an accurate and afforda-ble option for RT-PCR at point-of-care without the need for sample pre-processing and laboratory handling. The Q-POC test would enable rapid diagnosis and clinical triage in acute care and other settings.


2020 ◽  
Vol 5 (2) ◽  
pp. 7-11
Author(s):  
Pia Marie Albano ◽  

At the start of the pandemic, the Philippines had to send swab samples to the Victorian Infectious Diseases Reference Laboratory in Melbourne, Australia for COVID-19 confirmation. With the increasing number of suspected cases needing confirmatory diagnostic testing, there was a demand to rapidly expand the capacity for widescale testing. Remarkably, within 200 days from announcement of the first confirmed COVID-19 case in the Philippines in January 30, 2020, the country has been able to expand its testing capacity from one national reference laboratory, the Research Institute for Tropical Medicine (RITM), to more than 100 licensed reverse transcription-polymerase chain reaction (RT-PCR) and cartridge-based PCR laboratories across the country. Due to the shortage of a trained clinical laboratory workforce, diagnostic centers are forced to hire additional personnel who have limited experience and technical knowledge and skills of molecular assays, especially in processing specimens, interpreting the results, identifying errors, and troubleshooting, in order to meet the demand of increased testing. Thus, the vulnerability to diagnostic errors, including cross-contamination, is increased and with the tendency for generating false positive results that can compromise the health of the patient and disrupt the efficacy of public health policies and public health response, surveillance programs, and restrictive measures for containing the outbreak. Hence, this review article aims to present the different sources of contamination in the laboratory setting where RT-PCR assays are conducted, as well as provide efficient, effective and feasible solutions to address these issues, most especially in low- and middle-income countries (LMICs) like the Philippines.


2021 ◽  
Vol 6 (1) ◽  
pp. 60
Author(s):  
Byeong-Heon Kil ◽  
Ji-Seong Park ◽  
Chan-Young Park ◽  
Yu-Seop Kim ◽  
Jong-Dae Kim

In this paper, we investigate an efficient structure for a point-of-care (POC) molecular diagnostic system based on the industrial Internet of things (IIoT). The target system can perform automated molecular diagnosis including DNA extraction, PCR amplification, and fluorescence detection. Samples and reagents are placed in a multi-room cartridge and loaded into the system. A rotating motor and a syringe motor control the cartridge to extract DNA from the sample. The extracted DNA is transferred to a polymerase chain reaction (PCR) chamber for DNA amplification and detection. The proposed system provides multiplexing of up to four colors. For POC molecular diagnostics, the World Health Organization demands features such as low volume, low cost, fast results, and a user-friendly interface. In this paper, we propose a system structure that can satisfy these requirements by using a PCR chip and open platform. A distributed structure is adopted for the convenience of maintenance, and a web-based GUI is adopted for the user’s convenience. We also investigated communication problems that may occur between system components. Using the proposed structure, the user can conveniently control from standard computing devices including a smartphone.


Author(s):  
Brooke Clemons ◽  
Joel Barratt ◽  
Meredith Lane ◽  
Yvonne Qvarnstrom ◽  
Allen E. Teal ◽  
...  

For complex clinical cases where a parasitic infection is suspected, it can be difficult for clinicians to recommend an appropriate laboratory test. These tests are usually pathogen-specific and require a certain degree of suspicion for the precise etiology. Recently, Flaherty et al. (2021) described an assay, the universal parasite diagnostic (UPDx) that can potentially provide a diagnosis of any parasite present in a specimen. Using primers that amplify DNA from all eukaryotes, UPDx differentiates several parasitic infections in blood by amplicon-based next-generation sequencing (NGS) of the 18S rDNA locus. As the state’s public health reference laboratory, the Parasitology Laboratory at the Wadsworth Center (New York, NY) receives specimens from patients who have potentially encountered a wide variety of parasites. As such, the ability to differentiate several blood parasites using a single assay is of interest. We assessed UPDx for its ability to confirm parasitic infections for 20 specimens that were previously identified by real-time PCR (RT-PCR). This included specimens positive for Babesia microti, Trypanosoma cruzi, Leishmania tropica, various Plasmodium species, and specimens comprising mixed Plasmodium sp. infections. Results obtained using UPDx were largely concordant with the RT-PCR assays. A T. cruzi positive specimen was negative by UPDx and for two mixed Plasmodium sp. infections only one species was detected. The results obtained for other specimens were concordant. We conclude that UPDx shows promise for the detection of blood parasites in diagnostic laboratories. As NGS becomes cheaper, assays like UPDx will become increasingly amenable to use in clinical settings.


2021 ◽  
Author(s):  
Yoshihiko Kiyasu ◽  
Masato Owaku ◽  
Yusaku Akashi ◽  
Yuto Takeuchi ◽  
Kenji Narahara ◽  
...  

Introduction Smart Gene is a point-of-care (POC)-type automated molecular testing platform that can be performed with 1 minute of hands-on-time. Smart Gene SARS-CoV-2 is a newly developed Smart Gene molecular assay for the detection of SARS-CoV-2. The analytical and clinical performance of Smart Gene SARS-CoV-2 has not been evaluated. Methods Nasopharyngeal and anterior nasal samples were prospectively collected from subjects referred to the local PCR center from March 25 to July 5, 2021. Two swabs were simultaneously obtained for the Smart Gene SARS-CoV-2 assay and the reference real-time RT-PCR assay, and the results of Smart Gene SARS-CoV-2 were compared to the reference real-time RT-PCR assay. Results Among a total of 1150 samples, 68 of 791 nasopharyngeal samples and 51 of 359 anterior nasal samples were positive for SARS-CoV-2 in the reference real-time RT-PCR assay. In the testing of nasopharyngeal samples, Smart Gene SARS-CoV-2 showed the total, positive and negative concordance of 99.2% (95% confidence interval [CI]: 98.4–99.7%), 94.1% (95% CI: 85.6–98.4%) and 99.7% (95% CI: 99.0–100%), respectively. For anterior nasal samples, Smart Gene SARS-CoV-2 showed the total, positive and negative concordance of 98.9% (95% CI: 97.2–99.7%), 98.0% (95% CI: 89.6–100%) and 99.0% (95% CI: 97.2–99.8%), respectively. In total, 5 samples were positive in the reference real-time RT-PCR and negative in Smart Gene SARS-CoV-2, whereas 5 samples were negative in the reference real-time RT-PCR and positive in Smart Gene SARS-CoV-2. Conclusion Smart Gene SARS-CoV-2 showed sufficient analytical performance for the detection of SARS-CoV-2 in nasopharyngeal and anterior nasal samples.


Pathogens ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1629
Author(s):  
Alexander Domnich ◽  
Andrea Orsi ◽  
Donatella Panatto ◽  
Vanessa De Pace ◽  
Valentina Ricucci ◽  
...  

Although the reverse transcription-polymerase chain reaction (RT-PCR) is considered a standard-of-care assay for the laboratory diagnosis of SARS-CoV-2, several limitations of this method have been described. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) is an alternative molecular assay and is potentially able to overcome some intrinsic shortcomings of RT-PCR. In this study, we evaluated the diagnostic performance of the novel HG COVID-19 RT-LAMP assay. In this retrospective analysis, a total of 400 routinely collected leftover nasopharyngeal samples with a known RT-PCR result were tested by means of the HG COVID-19 RT-LAMP assay. The overall sensitivity and specificity values of HG COVID-19 RT-LAMP versus RT-PCR were 97.0% (95% CI: 93.6–98.9%) and 98.5% (95% CI: 95.7–99.7%), respectively. Inter-assay agreement was almost perfect (κ = 0.96). Concordance was perfect in samples with high viral loads (cycle threshold < 30). The average time to a positive result on RT-LAMP was 17 min. HG COVID-19 RT-LAMP is a reliable molecular diagnostic kit for detecting SARS-CoV-2, and its performance is comparable to that of RT-PCR. Shorter turnaround times and the possibility of performing molecular diagnostics in the point-of-care setting make it a valuable option for facilities without sophisticated laboratory equipment.


Author(s):  
E. G. Fomina ◽  
E. E. Grigorieva ◽  
E. P. Scheslenok ◽  
P. A. Semizhon ◽  
S. V. Tkachev ◽  
...  

Molecular diagnostic tests based on PCR preceded by reverse transcription (RT-PCR) are now used commonly for the detection of viral pathogens with RNA genomes. The application of internal controls to validate the entire process of these assays is necessary to prevent false-negative results caused by inhibition or inefficient extraction. In the present study a strategy to produce a new type of internal control for RT-PCR based on recombinant retroviral particles is described. Cell clones stably producing retroviral particles were established by transfecting GP+env-AM12 packaging cells with constructed MoMuLV-derived retroviral vector pLneo/gfp and subsequent cultivation on selective medium with G418. The egfp gene was used as a target for primers and hybridization probe design for real-time RT-PCR assay and as a marker for flow cytometry analysis of eGFP expression by transfected cells. The developed internal control is stable and ribonuclease resistant, economical to produce, noninfectious and safe for routine use. It closely mimics the natural virus and could be successfully used to monitor all the stages of RT-PCR, including nucleic acid extraction, RNA reverse transcription and amplification.


2021 ◽  
Author(s):  
Pratiksha Chheda ◽  
Dama Tavisha ◽  
Bhalerao Rahul ◽  
Bagwan Jamir ◽  
Bhat Devdatta ◽  
...  

Abstract Rapid diagnostic tests are of great importance in hospital settings during the current outbreak of SARS-CoV-2. The clinical patient management and spread of infection is critically dependent on molecular assays with shortest possible turn-around time. Here we report performance of a point of care Abbott ID NOW COVID-19 assay in comparison to routinely used real-time RT-PCR assay on 205 clinical specimens. Overall agreement of ID NOW was found to be 93.7% with positive percent agreement (PPA) of 91.8% and negative percent agreement (NPA) of 95.4%. Based on our findings, low turnaround time, minimal infrastructure need and ease of performing the assay, Abbott ID NOW COVID-19 assay can be considered as a point of care test in hospital settings.


2020 ◽  
Author(s):  
William Stokes ◽  
Byron M. Berenger ◽  
Takshveer Singh ◽  
Ifueko Adeghe ◽  
Angela Schneider ◽  
...  

INTRODUCTIONPoint of care diagnostic tests for SARS-CoV-2, such as the ID NOW, have great potential to help combat the COVID-19 pandemic. The ID NOW is approved by the United States Food and Drug Administration (FDA) for the detection of SARS-CoV-2 in symptomatic individuals within the first 7 days of symptom onset for COVID-19 if tested within 1 hour of specimen collection. However, clinical data on the performance of the ID NOW is limited, with many studies deviating from the manufacturer’s instructions and/or having small sample size.METHODSAdults with COVID-19 in the community or hospital were recruited into the study. Paired throat swabs were collected, with one throat swab transported immediately in an empty sterile tube to the laboratory for ID NOW testing, and the other transported in universal transport media and tested by an in-house SARS-CoV-2 RT-PCR assay targeting the E-gene. Positive percent agreement (PPA) was calculated.RESULTS133 individuals were included in the study. 129 samples were positive on either the ID NOW and/or RT-PCR. Assuming any positive result on either assay represents a true positive, PPA of the ID NOW compared to RT-PCR with 95% confidence intervals was 89.1% [82.0% - 94.1%] and 91.6% [85.1% - 95.9%], respectively. When analyzing individuals with symptoms ≤ 7 days and who had the ID NOW performed within an hour, ID NOW PPA increased to 98.2%.DISCUSSIONIn this study, SARS-CoV-2 results from the ID NOW were reliable, especially when testing was adhered to manufacturer’s recommendations.


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