ABSTRACT
Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has created high demand for molecular kits and consumables for mass screening of suspected individuals. Direct real-time polymerase chain reaction (RT-PCR) assay without nucleic acid extraction has several advantages in saving testing time and cost and helps in the rapid reporting of SARS-CoV-2. The present study evaluated the analytical performance of four SARS-CoV-2 RT-PCR for direct RT-PCR testing using preheated specimens.Methods A total of 100 clinical specimens were selected and divided into three different groups: (1) group I: 20 SARS-CoV-2 positive specimens with high viral load, viz., low Ct values (< 30 Ct), (2) group II: 50 SARS-CoV-2 positive specimens with low viral load, viz., high Ct values (> 30 Ct), and (3) group III: 30 SARS-CoV-2 negative specimens. Specimens were heat-inactivated at 70 >= C for 10 minutes and cooled down at 4 >= C and were evaluated for standard and direct RT-PCR method by using ViralDtect-II Multiplex Real-Time PCR kit, TaqPath COVID-19 Combo kit, COVIDsure Pro Multiplex RT-PCR kit, and Hi-PCR Coronavirus (COVID-19) Multiplex Probe PCR kit.Results Results showed that except ViralDtect-II kit, the other three TaqPath COVID-19 Combo kit, COVIDsure Pro kit, and Hi-PCR Coronavirus (COVID-19) RT-PCR kit were able to amplify all the SARS-CoV-2 genes in the direct RT-PCR method using preheated specimens. In group I specimens, 100% sensitivity was observed in all three RT-PCR kits. In group II specimens, COVIDsure Pro kit was found to be superior among other kits.Conclusion Direct RT-PCR method during pandemic situation is valuable and cost effective for the detection of SARS-CoV-2. All three TaqPath COVID-19 Combo kit, COVIDsure Pro kit, and Hi-PCR Coronavirus (COVID-19) RT-PCR kit can be used for direct RT-PCR method and COVIDsure Pro kit performance was found to be superior among all.
ABSTRACT
Introduction: Novel Coronavirus Disease 2019 (COVID-19) caused by the Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) has resulted in an unprecedented global pandemic. Real Time Polymerase Chain Reaction (RT-PCR) tests are being used in the diagnosis of COVID-19 worldwide however mutations in the SARS-CoV-2 genome have generated many SARS-CoV-2 genome variants and which may affect the correct Reverse transcriptase-Real time Polymerase Chain Reaction (RT-PCR) diagnosis. Aim: To confirm and study the incidence of the non amplification of the SARS-CoV-2 Nucleocapsid gene (N gene) target among known SARS-CoV-2 positive samples. Materials and Methods: This retrospective observational study was carried out at the State Virology Laboratory, Gandhi Medical College, Bhopal, Madhya Pradesh, India during January 2021 to May 2021. During the study period, a total of 159 SARS-CoV-2 positive samples were failed to amplify the N gene target. To investigate the non amplification of N gene target of SARSCoV-2, a total of 20 samples were selected and retested using the initially used RT-PCR kit (VIRALDTECT RT-PCR kit) and also with the two different RT-PCR kits (TaqPath RT-PCR kit and Hi-PCR RT-PCR kit) which also contain primers/probes for the SARS-CoV-2 N gene target. Results: Amplification and detection of the SARS-CoV-2 N target gene was not observed in VIRALDTECT RT-PCR test results. In contrast, amplification was detected in the N gene target of SARS-CoV-2 while using the TaqPath and Hi-PCR kits. Obtained results confirm the failure of the annealing of VIRALDTECT kit N gene primer/probe and suggest the possible mutation event in the SARS-CoV-2 N gene among the N gene non amplified samples. Conclusion: Present study reports, the incidence of non amplification of SARS-CoV-2 N gene, where the RT-PCR kit failed to detect N gene target and seriously affect RT-PCR diagnosis. Hence, the study emphasises the revalidation of commercially available SARS-CoV-2, RT-PCR kits to identify these kinds of failure incidence.
ABSTRACT
COVID-19 has exposed the inequalities and polarisation of South African communities and institutions of higher learning on the continuum of privilege. As nine social work educators, we share our reflections on how we traversed the higher education space during the beginning of the pandemic, using an autoethnography lens, with the pedagogy of discomfort and critical social work theory as the threads in the complex tapestry of our stories. We describe our orientations as social work educators, the successes, challenges, and recommendations on reimagining and reframing learning and teaching in relation to student-institutional relationships, boundaries and support.
ABSTRACT
Introduction: The whole world is facing an ongoing global health emergency of COVID-19 disease caused by the SARS-CoV-2. Real-Time Reverse Transcription-Polymerase Chain Reaction (RT-PCR) is a gold standard in the detection of SARS-CoV-2 infection. Presently, many single tube multiple gene target RTPCR kits have been developed and are commercially available for Corona Virus Disease 2019 (COVID-19) diagnosis. Aim: To evaluate the performance of seven COVID-19 RT-PCR kits (DiagSure, Meril, VIRALDTECT II, TruPCR, Q-line, Allplex and TaqPath) which are commercially available for COVID-19 RT-PCR diagnosis. Materials and Methods: This observational study was conducted at the State Virology Laboratory (SVL), Gandhi Medical College, Bhopal, Madhya Pradesh, India. Seven commercially available kits have been evaluated on the basis of: (i) number of SARS-CoV-2 specific gene target;(ii) human housekeeping genes as internal control;(iii) RT-PCR run time;and (iv) kit performances to correctly detect SARS-CoV-2 positive and negative RNA samples. A total of 50 RNA samples (left over RNA) were included, master mix preparation, template addition and RT-PCR test has been performed according to kits literature. At the end of PCR run, mean and standard deviation of obtained cut-off of all kits were calculated using Microsoft Excel. Results: All seven RT-PCR kits performed satisfactory regarding the reproducibility and they could correctly identify 30 positive and 20 negative RNA samples. RNA samples (group C) having low viral loads with a high Cycle threshold (Ct) value (>30) were also detected by all these seven kits. Obtained Ct values of each group was in parallel range in comparison with the initial testing Ct values. Kits were found to be superior which contains primers and probes for three SARS-CoV-2 specific gene targets, have human housekeeping gene as internal control and taking less time to complete RT-PCR. Conclusion: All seven COVID-19 RT-PCR kits included in this study demonstrated satisfactory performance and can be used for the routine molecular diagnosis of COVID-19 disease.