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E-Learning has shown to be an important resource, particularly in recent times due to the limitations in the Sars-CoV-2 pandemic. Several ways to deliver lessons through the Internet were used but both instructors and students complained about visual outputs. An evaluation of the most proficient techniques to create video-based lessons is highly relevant and critical. Seventy-eight students participated to 30 h of university online courses delivered through MS Teams, in which OBS (Open Broadcaster Software) Studio was used to create the lessons. The software allowed merging: a) MS Powerpoint slides, b) the instructor through a webcam, c) pictures of background sceneries. After the end of the courses, students filled in a questionnaire evaluating pictures taken from different e-learning sceneries. The OBS-based situation obtained the best evaluation in all measures (fruition, attention keeping and promotion of learning) and the highest rank when participants were asked to compare all the sceneries. These results confirm that students prefer reality-based sceneries, in which the most informative aspects (face, body and voice of the instructor, and the slides used for the lesson) are all present. Beside other obvious factors related to the quality of teaching, e-learning should also definitely consider visual features. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
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Introduction: SARS-CoV-2 immune-response is mediated by both humoral and cellular immunity. However, since Ab levels wane faster than SARS-CoV-2 specific T cells immunity, cellular immunity represents an important factor for COVID-19 immune defence. Determining immunoreactivity of SARS-CoV-2 specific T cells is of clinical relevance in transplant recipients or patients treated with immunomodulant therapy. SARS-CoV-2 specific T cells assays are currently based on ELISA, whilst rapid tests are pivotal for real-time patients' evaluation. In this study, a novel direct real-time PCR (dRT-PCR) targeting mRNA of CXCL10 for measuring SARS-CoV-2 specific T cells, was tested and evaluated. Method(s): A total of 104 healthcare workers, with two or three doses of homologous (Pfizer/BioNTech, n = 82) or heterologous (Pfizer/BioNTech and Vaxzevria or Moderna, n = 22) vaccinations were asked to collect a blood (Li-He) sample. Blood was stimulated overnight with SARS-CoV-2 spike peptides (S-peptide) or treated with non-stimulating substance. Stimulated/treated samples were diluted in Buffer A, mixed with dqTACT MS then loaded into the cartridge. The analysis was performed using SCV2 T Activation kit, bCube and bApp (Hyris srl, Lodi, Italy), equipped by an automatic result interpretation based on artificial intelligence. For a subgroup of 49 samples, IFN-y releases to SARS-CoV-2 spike peptides were tested by Quant-T-Cell SARS-CoV-2 and ELISA (Euroimmune, Lubeck, Germany). Result(s): Seventy-nine (75.9%) and 25 (24.1%) were females and males, respectively. Twenty-nine subjects were previously infected by SARS-CoV-2. Overall mean age (+/- SD) was 45.9+/-13.3 years. At qualitative analyses, 97 subjects (93.2%) resulted reactive to S-peptides, 3 (2.8%) were borderline and 4 were negative (3.8%). These negatives had their third vaccinal dose in December/November 2021. Previous infected individuals presented reactivity to S-peptides, with the exception of one subject with resulted reactive also in the untreated sample. Samples tested with both dRT-PCR and ELISA perfectly agreed (100%) with both methods. At quantitative analyses, between-assay correlation was 0.32 (p<0.001). Conclusion(s): Hyris dRT-PCR appeared accurate for determining presence or absence of immunoreactivity of SARS-CoV-2 specific T cell, especially when rapid analyses are required, such as for organ transplantation.
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Background: The Severe Acute Respiratory Syndrome Coronavirus 2 related (SARS-CoV-2) has rapidly spread originating into the fifth documented pandemic wave. Dried blood spot (DBS) provides an alternative method to the venous blood samples to determine Ab, presenting several advantages, including the practicability, especially in infants, and the possibility to test a higher number of samples in a limited time. The main goal of this study was to measure seroprevalence of anti-SARS-CoV-2 IgG Ab in newborns, using DBS collected from January 2020 to December 2021. Method(s): Anti-SARS-CoV-2 IgG levels were determined using DBS by Anti-SARS-CoV-2 QuantiVac IgG ELISA assay (Euroimmune, Lubeck, Germany). Result(s): Preliminary analyses included 515 DBS from newborns, 54% males and 46% females, collected 2-3 days after birth. Overall, mean IgG levels, although below the positive threshold (>= 35.2 kBAU/L), were significantly higher in 2021 (Feb/21 and Mar/21), with respect to 2020 (Feb/20: 8.6+/-3.5, n=99 vs Feb/21: 28.1+/-42.8, n=40;Mar/20: 11.6+/-5.1, n=94 -Mar/21: 16.8+/-11.6, n=39, mean kBAU/L +/- DS, p<0.005). Moreover, an increased number of positive samples were found in 2021 (4/44 Gen/21;8/40 Feb/21;2/39 Mar/21). As expected, a trend of increase around 5% in DBS tested positive for anti-SARSCoV-2 IgG were found in December 2021, where IgG were above the positive threshold in 41.54% of DBS (450.926+/-873.291, mean kBAU/L +/- DS, n=65). Conclusion(s): In these preliminary data, newborn DBS seems to reflect population-wide infection rates during the studied periods. This suggests a potential role for DBS in COVID-19 surveillance, especially in infants and in areas where viral testing is limited.
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Background and Aim: Salivary SARS-CoV-2 Ab determination could be suitable for monitoring the viral spread and vaccination efficacy, especially in pediatric patients. We investigated N/S1-RBD IgG antibody levels in salivary samples of infectious-naïve vaccinated subjects and of COVID-19 patients, further comparing levels with serum anti-SARS-CoV-2 S-RBD IgG. Methods: A total of 72 subjects were enrolled at the Padova University Hospital: 36 COVID-19 patients and 36 health care workers (HCW), who underwent a complete vaccination campaign with BNT162b2 (BioNTech/Pfizer). All collected a salivary sample, using Salivette (Sarstedt, Nümbrecht Germany). For 9 HCW, salivary samples were collected at three different times within the same day (before breakfast, at 10 am, and after lunch). A serum sample was also collected for all individuals. Time post symptoms onset or time from the first vaccine were also recorded. Salivary COVID-19 N/S1 RBD (sal-IgG) ELISA (RayBiotech, GA, USA) and anti-SARS-CoV-2 S-RBD IgG Ab (ser-IgG) (Snibe Diagnostics, Shenzhen, China) were used for determining IgG Ab. Results: Subjects' mean age (±sd) was 35.8±18.2 yrs. Age significantly differed (p<0.001) from COVID-19 patients [29.7±17.3 yrs] and HCW [47.1±12.9 yrs]. Positive sal-IgG were found in 70/72 (97.2%) samples;in sera, 71/72 (98.6%) samples were positive to ser-IgG. The sal-IgG median levels differed from COVID-19 to vaccinated HCW, being in salivary samples 0.21 kAU/L and 0.8 kAU/L (p =0.030), respectively;median levels for ser-IgG in COVID-19 and vaccinated HCW were 135 kBAU/L and 940 kBAU/L, respectively (p<0.001). Salivary IgG levels were not influenced by time post-symptom onset or time post-vaccination, both on vaccinated HCW (rho= -0.147, p=0.402) and COVID-19 subjects (rho=0.0267, p=0.986). Ser-IgG levels was not influenced by the time post-symptom onset for COVID-19 subjects (rho=0.102, p=0.419), while a strong significant correlation was found with time post-vaccination in HCW (rho=-0.6292, p<0.001). Sal-IgG levels were notinfluenced by the daytime of collection (rho=0.148, p=0.373). Passing-Bablok regressions showed that sar- IgG and ser-IgG comparability was assessable only when ser-IgG values were divided by 1000, being slope and intercept 0.068 (95%CI: 0.069-0.341) and 0.221 (95%CI:- 0.097 to 0.786), respectively. Conclusions: Salivary IgG is efficiently detectable both in COVID-19 and in vaccinated individuals and analyses appeared to be not influenced by the daytime of collection. The analyses performed showed that, overall, sal-IgG were lower than ser-IgG, and thus comparability with serum levels needs to be better explored.
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Background. One of the strategies suggested for the containment of SARS-CoV-2 pandemic is testing at risk populations with rapid turn-out of results, contact tracing and isolation of infected individuals, at least until vaccination programs have been completed. Molecular testing of naso-pharyngeal swabs (NPS) is considered gold-standard, but antigenic testing should offer the advantage of being more rapid. Aim. The aim of this study was to evaluate the clinical performance of two chemiluminescent immunoassays on laboratory automated platforms, LIAISON® SARS-CoV-2 Ag Assay (DiaSorin) and Elecsys SARS-CoV-2 Antigen (Roche), to detect SARS-CoV-2 N antigen in NPS. Patients and Methods. A total of 281 subjects were consecutively enrolled (116 M, 165 F) from three different cohorts: 14 were COVID-19 in-patients (Group 1), 149 were patients enrolled at the emergency unit (Group 2) while 118 were healthcare employees under SARS-CoV-2 periodic surveillance (Group 3). All subjects underwent NPS with eSwab Copan. Antigen and molecular testing were performed soon after collection. Results. Thirty subjects were SARS-CoV-2 positive at molecular testing. Liaison antigen was positive (>200 TCID50/ml) in 22/30 (Se=73.3%), equivocal (100-200 TCID50/ml) in 4/30 and negative (<100 TCID50/ml) in 4/30 subjects. Specificity was 61.8% since 60/157 negative samples had equivocal results. With Elecsys sensitivity was 75.9% and specificity 99.5%. ROC curves were performed to compare the two assays and to identify the best cut-off. The areas under the curves were not different (η2=0.14;Prob>η2=0.7077). The highest likelihood ratio for Liaison corresponded to 150 TCID50ml cut-off, while for Elecsys to 1 index value. With these thresholds sensitivity of these two assays were 86% and 87% respectively, with 99% specificity. The limitations in sensitivity were due to false negative results for samples with Ct values at molecular analysis higher than 25. No false negative case was recorded among those with Ct lower than 25. Conclusions. In conclusion NPS SARS-CoV-2 antigen testing with chemiluminescent immunoassays allows the rapid detection of positive samples with a sensitivity and specificity that meet the recommendations of the WHO for this type of testing.
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Introduction. Saliva has been proposed as a valid alternative to naso-pharyngeal swabs for detecting viral SARS-CoV-2 RNA sequences. In addition salivary glands have been described as a potential SARSCoV-2 virus reservoir, thus supporting the search for antibodies in saliva. Furthermore, the non-invasive nature of saliva collection is conducive to self-collection, patients' compliance for repeated testing, and reduction of risk to operators, thus making saliva an eligible matrix in the SARS-CoV-2 diagnostic process. Aim. The aim of this study was to verify whether standardized and safe saliva collection is suitable for SARS-CoV-2 molecular detection and IgA class antibody measurement. Methods. A total of 49 COVID-19 patients hospitalized at the University-Hospital of Padova (Italy) and 326 subjects who underwent screening underwent naso-pharyngeal (NP) swab and saliva collection using Salivette®. Repeat blood collections were performed to evaluate hematological and coagulation parameters, biochemical markers of inflammation, and renal, liver, heart and pancreatic involvement in hospitalized patients. In all patients and subjects, saliva SARS-CoV-2 (gene E) rRT-PCR was undertaken in parallel with NP swabs. Salivary IgA and serum IgA, IgG, IgM were measured on samples from hospitalized patients. Results. NP swabs were SARSCoV-2 positive in 9/49 patients. The comparison with saliva testing was possible for 43/49 patients, 7 of whom shared positivity, and 35 negativity while in one, the saliva result, not NP-swab, was positive. Positive molecular testing results were significantly associated with disease duration (p=0.0049). All the 326 screened subjects were SARS-CoV-2 negative on both NP and saliva swabs. Among the 27 saliva samples tested for IgA, 18 were IgA positive. Salivary IgA positivity was significantly associated with pneumonia (p=0.002) and CRP values (p=0.0183), not with other clinical and molecular data, or with immunoglubulins in serum.Conclusions. The results reported in the present study demonstrate that a standardized and safe saliva collection method can be adopted to detect SARS-CoV-2 infection in alternative to NP-swabs. Preliminary data on salivary IgA also support the use of saliva in local adaptive immunity patient monitoring.
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We present a 38 years female patient with known difficult airway associated with an important anatomic deformation due to a tumoral removal back in 2014 (maxilectomy). This patient was scheduled for a new tumoral resection at the base of the skull, which was considered a potential regrowth of her maxilar sinus cancer, and because of that, the surgery admitted no delays. A multi-disciplinary approach is convenied and an AFOi with topical airway anesthesia and dexmedetomidine sedation is planned to secure the airway during surgery. The main Objective was to optimize the protective measures against SARS Cov2 transmission while securing spontaneous ventilation and patient collaboration during the procedure. To achieve this it was necessary a complex and multi-disciplinary teamwork between de intervening personal. Eventually the airway approach was successful and the surgery was carried out uneventfully. The patient was extubate and taken to the post anesthesia care unit with no recall nor sequel of the procedure. © 2020 Sociedad de Anestesiologia de Chile. All rights reserved.