IL-10/IL-6 ratio from nasal & oral swab samples, acts as an inflammatory indicator for COVID-19 patients infected with the delta variant.

Background: Hyper-inflammatory immune response of SARS-CoV-2 is often characterized by the release of multiple pro-inflammatory cytokines with an impact on the expression of numerous other interleukins (ILs). However, from oral and nasal swab samples the specific quantitative association of the different IL-markers with the disease progression and its relationship with the status of vaccination remains unclear. Materials and methods: Patients' combined oral and nasal swab samples were collected from both non-vaccinated and double-vaccinated individuals with high (Ct value < 25) and low (Ct value > 30) viral loads, along with uninfected donors. None of the patients were critically ill, or needed ICU support. The expression of different cytokines (IL6, IL10, IL1B, IFNG) and mucin (MUC5AC, MUC1) markers were assessed between different groups by qRT-PCR. The important cytokine markers differentiating between vaccinated and non-vaccinated patients were identified by PCA. Conclusion: IL6 expression was higher in non-vaccinated COVID-19 patients infected with delta-variant irrespective of their viral-load compared to uninfected individuals. However, in double-vaccinated patients, only in high viral-load patients (Ct value < 25), IL6 expression increased. In high viral-load patients, irrespective to their vaccination status, IL10 expression was lower compared to the uninfected control group. Surprisingly, IL10 expression was lower in double-vaccinated patients with Ct value > 30. IL1B, and IFNG expression remained unaltered in uninfected and infected individuals. However, MUC5AC expression was lower in non-vaccinated patients with Ct value < 25 compared to control group. Our study unveiled that IL10/IL6 ratio can be used as a biomarker for COVID-19 patients upon proper establishment of it in a clinical setting.

Clinical evaluation of anterior nasal cavity swab specimens by a rapid antigen test using a GLINE-2019-nCoV Ag Kit to diagnose COVID-19.

The promising diagnostic performance of rapid antigen tests (RATs) using non-invasive anterior nasal (AN) swab specimens to diagnose COVID-19 has been reported. A large number of RATs are commercially available; however, the careful assessment of RATs is essential prior to their implementation in clinical practice. We evaluated the clinical performance of the GLINE-2019-nCoV Ag Kit as a RAT using AN swabs in a prospective, blinded study. Adult patients who visited outpatient departments and received SARS-CoV-2 tests between August 16 and September 8, 2022, were eligible for this study. Patients who were aged under 18 years and patients without appropriate specimens were excluded. Two sets of AN and nasopharyngeal (NP) swabs were collected from all patients. Each set of specimens was tested by the RAT and quantitative reverse-transcription polymerase chain reaction (RT-qPCR). Of the 138 recruited patients, 84 were positive and 54 were negative by RT-qPCR using NP swabs. The positive agreement rate between RT-qPCR using NP swabs and RAT using AN swabs was 78.6% (95% confidence interval [CI], 68.3%-86.8%), the negative agreement rate was 98.1% (95% CI, 90.1%-99.9%), and the overall agreement rate was 86.2% (95% CI, 79.3%-91.5%), with a κ coefficient of 0.73. The positive agreement rate in the early phase (≤3 days from symptom onset) was >80%, but this fell to 50% in the late phase (≥4 days). This study demonstrates that the GLINE-2019-nCoV Ag Kit using AN swabs has good clinical performance and might be a reliable alternative method for diagnosing COVID-19.

Utility of COVID-19 antigen testing in the emergency department.

BACKGROUND: The BinaxNOW coronavirus disease 2019 (COVID-19) Ag Card test (Abbott Diagnostics Scarborough, Inc.) is a lateral flow immunochromatographic point-of-care test for the qualitative detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein antigen. It provides results from nasal swabs in 15 minutes. Our purpose was to determine its sensitivity and specificity for a COVID-19 diagnosis. METHODS: Eligible patients had symptoms of COVID-19 or suspected exposure. After consent, 2 nasal swabs were collected; 1 was tested using the Abbott RealTime SARS-CoV-2 (ie, the gold standard polymerase chain reaction test) and the second run on the BinaxNOW point of care platform by emergency department staff. RESULTS: From July 20 to October 28, 2020, 767 patients were enrolled, of which 735 had evaluable samples. Their mean (SD) age was 46.8 (16.6) years, and 422 (57.4%) were women. A total of 623 (84.8%) patients had COVID-19 symptoms, most commonly shortness of breath (n = 404; 55.0%), cough (n = 314; 42.7%), and fever (n = 253; 34.4%). Although 460 (62.6%) had symptoms ≤7 days, the mean (SD) time since symptom onset was 8.1 (14.0) days. Positive tests occurred in 173 (23.5%) and 141 (19.2%) with the gold standard versus BinaxNOW test, respectively. Those with symptoms >2 weeks had a positive test rate roughly half of those with earlier presentations. In patients with symptoms ≤7 days, the sensitivity, specificity, and negative and positive predictive values for the BinaxNOW test were 84.6%, 98.5%, 94.9%, and 95.2%, respectively. CONCLUSIONS: The BinaxNOW point-of-care test has good sensitivity and excellent specificity for the detection of COVID-19. We recommend using the BinasNOW for patients with symptoms up to 2 weeks.

Platelet Rich Fibrin for Post Covid Nasal Swab Cerebrospinal Fluid Leak

Nasopharyngeal swab collection procedure has been used as a part of COVID-19 testing. Few cases of cerebrospinal fluid (CSF) leak following nasopharyngeal swab have been reported so far. Here, we report an interesting case of CSF leak following nasopharyngeal swab for COVID testing which we repaired using platelet-rich fibrin as an outpatient department procedure.

Nasal swab as an alternative specimen for the detection of severe acute respiratory syndrome coronavirus 2.

Background and Aims: The coronavirus disease 2019 (COVID-19) has brought serious threats to public health worldwide. Nasopharyngeal, nasal swabs, and saliva specimens are used to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, limited data are available on the performance of less invasive nasal swab for testing COVID-19. This study aimed to compare the diagnostic performance of nasal swabs with nasopharyngeal swabs using real-time reverse transcription polymerase chain reaction (RT-PCR) considering viral load, onset of symptoms, and disease severity. Methods: A total of 449 suspected COVIDCOVID-19 individuals were recruited. Both nasopharyngeal and nasal swabs were collected from the same individual. Viral RNA was extracted and tested by real-time RT-PCR. Metadata were collected using structured questionnaire and analyzed by SPSS and MedCalc software. Results: The overall sensitivity of the nasopharyngeal swab was 96.6%, and the nasal swab was 83.4%. The sensitivity of nasal swabs was more than 97.7% for low and moderate C t values. Moreover, the performance of nasal swab was very high (>87%) for hospitalized patients and at the later stage >7 days of onset of symptoms. Conclusion: Less invasive nasal swab sampling with adequate sensitivity can be used as an alternative to nasopharyngeal swabs for the detection of SARS-CoV-2 by real-time RT-PCR.

Metavirome Analysis Reveals a High Prevalence of Porcine Hemagglutination Encephalomyelitis Virus in Clinically Healthy Pigs in China.

Six swine coronaviruses (SCoVs), which include porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), porcine hemagglutination encephalomyelitis virus (PHEV), porcine respiratory coronavirus (PRCV), swine acute diarrhea syndrome coronavirus (SADS-CoV), and porcine delta coronavirus (PDCoV), have been reported as infecting and causing serious diseases in pigs. To investigate the genetic diversity and spatial distribution of SCoVs in clinically healthy pigs in China, we collected 6400 nasal swabs and 1245 serum samples from clinically healthy pigs at slaughterhouses in 13 provinces in 2017 and pooled them into 17 libraries by type and region for next-generation sequencing (NGS) and metavirome analyses. In total, we identified five species of SCoVs, including PEDV, PDCoV, PHEV, PRCV, and TGEV. Strikingly, PHEV was detected from all the samples in high abundance and its genome sequences accounted for 75.28% of all coronaviruses, while those belonging to TGEV (including PRCV), PEDV, and PDCoV were 20.4%, 2.66%, and 2.37%, respectively. The phylogenetic analysis showed that two lineages of PHEV have been circulating in pig populations in China. We also recognized two PRCVs which lack 672 nucleotides at the N-terminus of the S gene compared with that of TGEV. Together, we disclose preliminarily the genetic diversities of SCoVs in clinically healthy pigs in China and provide new insights into two SCoVs, PHEV and PRCV, that have been somewhat overlooked in previous studies in China.

V-tube: The first prototype of pneumatic actuated soft nasal swab for COVID-19 screening

Swab and tube are widely used in respiratory specimen collections for current COVID-19 screening. This paper proposes the design of a novel pneumatic actuated soft nasal swab, named V-tube. The V-tube consists of three main parts: an outer tube, a cap integrated with broth container and an active film (AF) that can be squeezed out of the tube under positive air pressure to collect nasal mucus cells. The working process and material selection of this swab is studied via Finite Element Analysis (FEA). It is expected to integrate the V-tube with a dual arm mobile collaborative robot (MCR) to accomplish nucleic acid sampling instead of medical staff. Therefore, a robot-applicable pneumatic system is designed to supply appropriate force to drive the V-tube. The potential manufacturing and control issues of the V-tube are discussed for further studies. © 2022 IEEE.

Visual Positioning of Nasal Swab Robot Based on Hierarchical Decision.

This study focuses on a robot vision localization method for coping with the operational task of automatic nasal swab sampling. The application is important in the detection and epidemic prevention of Corona Virus Disease 2019 (COVID-19) to alleviate the large-scale negative impact of individuals suffering from pneumonia owing to COVID-19. In this method, the idea of a hierarchical decision network is used to consider the strong infectious characteristics of the COVID-19, which is followed by processing the robot behavior constraint condition. The visual navigation and positioning method using a single-arm robot for sampling is also planned, which considers the operation characteristics of medical staff. In the decision network, the risk factor for potential contact infection caused by swab sampling operations is established to avoid the spread among personnel. A robot visual servo control with artificial intelligence characteristics is developed to achieve a stable and safe nasal swab sampling operation. Experiments demonstrate that the proposed method can achieve good vision positioning for the robots and provide technical support for managing new major public health situations.

Seed amplification assay of nasal swab extracts for accurate and non-invasive molecular diagnosis of neurodegenerative diseases.

Nasal swabs are non-invasive testing methods for detecting diseases by collecting samples from the nasal cavity or nasopharynx. Dysosmia is regarded as an early sign of coronavirus disease 2019 (COVID-19), and nasal swabs are the gold standard for the detection. By nasal swabs, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acids can be cyclically amplified and detected using real-time reverse transcriptase-polymerase chain reaction after sampling. Similarly, olfactory dysfunction precedes the onset of typical clinical manifestations by several years in prion diseases and other neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. In neurodegenerative diseases, nasal swab tests are currently being explored using seed amplification assay (SAA) of pathogenic misfolded proteins, such as prion, α-synuclein, and tau. These misfolded proteins can serve as templates for the conformational change of other copies from the native form into the same misfolded form in a prion-like manner. SAA for misfolded prion-like proteins from nasal swab extracts has been developed, conceptually analogous to PCR, showing high sensitivity and specificity for molecular diagnosis of degenerative diseases even in the prodromal stage. Cyclic amplification assay of nasal swab extracts is an attractive and feasible method for accurate and non-invasive detection of trace amount of pathogenic substances for screening and diagnosis of neurodegenerative disease.

Implementation of a Student-Teacher-Based Blended Curriculum for the Training of Medical Students for Nasopharyngeal Swab and Intramuscular Injection: Mixed Methods Pre-Post and Satisfaction Surveys.

BACKGROUND: The COVID-19 pandemic caused a major disruption in the health care sector with increased workload and the need for new staff to assist with screening and vaccination tasks. Within this context, teaching medical students to perform intramuscular injections and nasal swabs could help address workforce needs. Although several recent studies discuss medical students' role and integration in clinical activities during the pandemic, knowledge gaps exist concerning their role and potential benefit in designing and leading teaching activities during this period. OBJECTIVE: The aim of our study was to prospectively assess the impact in terms of confidence, cognitive knowledge, and perceived satisfaction of a student-teacher-designed educational activity consisting of nasopharyngeal swabs and intramuscular injections for the training of second-year medical students in the Faculty of Medicine, University of Geneva, Switzerland. METHODS: This was a mixed methods pre-post surveys and satisfaction survey study. Activities were designed using evidence-based teaching methodologies based on the SMART (specific, measurable, achievable, realistic, and timely) criteria. All second-year medical students who did not participate in the activity's old format were recruited unless they explicitly stated that they wanted to opt out. Pre-post activity surveys were designed to assess perception of confidence and cognitive knowledge. An additional survey was designed to assess satisfaction in the mentioned activities. Instructional design was blended with a presession e-learning activity and a 2-hour practice session with simulators. RESULTS: Between December 13, 2021, and January 25, 2022, a total of 108 second-year medical students were recruited; 82 (75.9%) students participated in the preactivity survey and 73 (67.6%) in the postactivity survey. Students' confidence in performing intramuscular injections and nasal swabs significantly increased on a 5-point Likert scale for both procedures-from 3.31 (SD 1.23) and 3.59 (SD 1.13) before the activity to 4.45 (SD 0.62) and 4.32 (SD 0.76) after the activity (P<.001), respectively. Perceptions of cognitive knowledge acquisition also significantly increased for both activities. For the nasopharyngeal swab, knowledge acquisition concerning indications increased from 2.7 (SD 1.24) to 4.15 (SD 0.83), and for the intramuscular injection, knowledge acquisition concerning indications increased from 2.64 (SD 1.1) to 4.34 (SD 0.65) (P<.001). Knowledge of contraindications for both activities increased from 2.43 (SD 1.1) to 3.71 (SD 1.12) and from 2.49 (SD 1.13) to 4.19 (SD 0.63), respectively (P<.001). High satisfaction rates were reported for both activities. CONCLUSIONS: Student-teacher-based blended activities for training novice medical students in commonly performed procedural skills seem effective for increasing their confidence and cognitive knowledge and should be further integrated within a medical school curriculum. Blended learning instructional design increases students' satisfaction about clinical competency activities. Future research should elucidate the impact of student-teacher-designed and student-teacher-led educational activities.

Evaluation of a laboratory-based high-throughput SARS-CoV-2 antigen assay.

OBJECTIVES: Antigen tests are an essential part of SARS-CoV-2 testing strategies. Rapid antigen tests are easy to use but less sensitive compared to nucleic acid amplification tests (NAT) and less suitable for large-scale testing. In contrast, laboratory-based antigen tests are suitable for high-throughput immunoanalyzers. Here we evaluated the diagnostic performance of the laboratory-based Siemens Healthineers SARS-CoV-2 Antigen (CoV2Ag) assay. METHODS: In a public test center, from 447 individuals anterior nasal swab specimens as well as nasopharyngeal swab specimens were collected. The nasal swab specimens were collected in sample inactivation medium and measured using the CoV2Ag assay. The nasopharyngeal swab specimens were measured by RT-PCR. Additionally, 9,046 swab specimens obtained for screening purposes in a tertiary care hospital were analyzed and positive CoV2Ag results confirmed by NAT. RESULTS: In total, 234/447 (52.3%) participants of the public test center were positive for SARS-CoV-2-RNA. Viral lineage B1.1.529 was dominant during the study. Sensitivity and specificity of the CoV2Ag assay were 88.5% (95%CI: 83.7-91.9%) and 99.5% (97.4-99.9%), respectively. Sensitivity increased to 93.7% (97.4-99.9%) and 98.7% (97.4-99.9%) for swab specimens with cycle threshold values <30 and <25, respectively. Out of 9,046 CoV2Ag screening tests from hospitalized patients, 21 (0.2%) swab specimens were determined as false-positive by confirmatory NAT. CONCLUSIONS: Using sample tubes containing inactivation medium the laboratory-based high-throughput CoV2Ag assay is a very specific and highly sensitive assay for detection of SARS-CoV-2 antigen in nasal swab specimens including the B1.1.529 variant. In low prevalence settings confirmation of positive CoV2Ag results by SARS-CoV-2-RNA testing is recommended.

Rapid, Sensitive, Label-Free Electrical Detection of SARS-CoV-2 in Nasal Swab Samples.

Rapid diagnosis of coronavirus disease 2019 (COVID-19) is key for the long-term control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) amid renewed threats of mutated SARS-CoV-2 around the world. Here, we report on an electrical label-free detection of SARS-CoV-2 in nasopharyngeal swab samples directly collected from outpatients or in saliva-relevant conditions by using a remote floating-gate field-effect transistor (RFGFET) with a 2-dimensional reduced graphene oxide (rGO) sensing membrane. RFGFET sensors demonstrate rapid detection (<5 min), a 90.6% accuracy from 8 nasal swab samples measured by 4 different devices for each sample, and a coefficient of variation (CV) < 6%. Also, RFGFET sensors display a limit of detection (LOD) of pseudo-SARS-CoV-2 that is 10 000-fold lower than enzyme-linked immunosorbent assays, with a comparable LOD to that of reverse transcription-polymerase chain reaction (RT-PCR) for patient samples. To achieve this, comprehensive systematic studies were performed regarding interactions between SARS-CoV-2 and spike proteins, neutralizing antibodies, and angiotensin-converting enzyme 2, as either a biomarker (detection target) or a sensing probe (receptor) functionalized on the rGO sensing membrane. Taken together, this work may have an immense effect on positioning FET bioelectronics for rapid SARS-CoV-2 diagnostics.

Providing Evidence for Dogma: Risk of Epistaxis After COVID-19 Nasal-Screening Swab.

OBJECTIVE: There is anecdotal evidence SARS-CoV-2 (COVID) RT-PCR screening nasal swabs confer an elevated epistaxis risk. We aimed to assess the association between epistaxis and exposure to a COVID nasal swab. STUDY DESIGN: A matched pairs design was used. SETTING: The study was performed in a single, integrated health care system. METHODS: All patients who received a single COVID nasal swab at our institution between April 2020 and March 2021 were included. McNemar's test was used to compare rates of epistaxis between the 7 days following the index COVID swab (hazard period), and the 7 days preceding the index COVID swab (control period). Conditional logistic regression was used to evaluate sociodemographic and clinical risk factors for epistaxis. RESULTS: A total of 827,987 participants were included, with 1047 epistaxis encounters. The prevalence of epistaxis during the hazard and control periods were 0.08% and 0.04%, respectively. Swab exposure was associated with 1.92-fold odds of epistaxis during the hazard period (95% confidence interval [1.73, 2.12]). Older age, Asian/Pacific Islander (PI) (compared to white), male sex, hypertension, prior facial trauma, and warfarin or direct-acting oral anticoagulant use were also associated with significantly increased odds of epistaxis (p ≦ 0.01). CONCLUSION: COVID nasal swabs are associated with increased odds of epistaxis. Physicians should counsel patients, particularly those at the highest risk, including a history of prior facial trauma, anticoagulants/antiplatelets, or hypertension.

Prospective population-level validation of the Abbott ID NOW severe acute respiratory syndrome coronavirus 2 device implemented in multiple settings for testing asymptomatic and symptomatic individuals.

OBJECTIVE: Diagnostic evaluation of the ID NOW coronavirus disease 2019 (COVID-19) assay in various real-world settings among symptomatic and asymptomatic individuals. METHODS: Depending on the setting, the ID NOW testing was performed using oropharyngeal swabs (OPSs) taken from patients with symptoms suggestive of COVID-19, asymptomatic close contacts, or asymptomatic individuals as part of outbreak point prevalence screening. From January to April 2021, a select number of sites switched from using OPS to combined oropharyngeal and nasal swab (O + NS) for ID NOW testing. For every individual tested, two swabs were collected by a health care worker: one swab (OPS or O + NS) for ID NOW testing and a separate swab (OPS or nasopharyngeal swab) for RT-PCR. RESULTS: A total of 129 112 paired samples were analysed (16 061 RT-PCR positive). Of these, 81 697 samples were from 42 COVID-19 community collection sites, 16 924 samples were from 69 rural hospitals, 1927 samples were from nine emergency shelters and addiction treatment facilities, 23 802 samples were from six mobile units that responded to 356 community outbreaks, and 4762 O + NS swabs were collected from three community collection sites and one emergency shelter. The ID NOW assay sensitivity was the highest among symptomatic individuals presenting to community collection sites (92.5%; 95% CI, 92.0-93.0%) and the lowest for asymptomatic individuals associated with community outbreaks (73.9%; 95% CI, 69.8-77.7%). Specificity was >99% in all populations tested. DISCUSSION: The sensitivity of ID NOW severe acute respiratory syndrome coronavirus 2 testing is the highest when used in symptomatic community populations not seeking medical care. Sensitivity and positive predictive value drop by approximately 10% when tested on asymptomatic populations. Using combined oropharyngeal and nasal swabs did not improve the performance of ID NOW assay.

Cerebrospinal fluid fistula as a complication of reverse transcriptase-polymerase chain reaction collection for the detection of coronavirus disease 2019: illustrative cases.

BACKGROUND: The most used method to detect coronavirus disease 2019 during the pandemic is reverse transcriptase-polymerase chain reaction with nasal swab. Despite being highly effective, the test does not leave the patient risk-free and can lead to serious complications. These can be traumatic nasal cerebrospinal fluid (CSF) fistula and its consequences, such as meningitis. OBSERVATIONS: In this article, the authors present 4 case reports and a literature review. The following MeSH terms in the research were used: "CSF leak case report and covid 19." Six results were found and after searching the references and keywords 16 articles were identified. By using them, the authors tried to clarify the etiology of the fistula, its influences, and complications. LESSONS: The authors conclude that professionals must receive training, since CSF fistula originates from technical failure and lack of anatomical knowledge. The diagnosis cannot be neglected because it can bring complications to the patient's health.

Mucosal Gene Expression in Response to SARS-CoV-2 Is Associated with Viral Load.

Little is known about the relationships between symptomatic early severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load and upper airway mucosal gene expression and immune response. To examine the association of symptomatic SARS-CoV-2 early viral load with upper airway mucosal gene expression, we profiled the host mucosal transcriptome from nasopharyngeal swab samples from 68 adults with symptomatic, mild-to-moderate coronavirus disease 19 (COVID-19). We measured SARS-CoV-2 viral load using reverse transcription-quantitative PCR (RT-qPCR). We then examined the association of SARS-CoV-2 viral load with upper airway mucosal immune response. We detected SARS-CoV-2 in all samples and recovered >80% of the genome from 95% of the samples from symptomatic COVID-19 adults. The respiratory virome was dominated by SARS-CoV-2, with limited codetection of other respiratory viruses, with the human Rhinovirus C being identified in 4 (6%) samples. This limited codetection of other respiratory viral pathogens may be due to the implementation of public health measures, like social distancing and masking practices. We observed a significant positive correlation between SARS-CoV-2 viral load and interferon signaling (OAS2, OAS3, IFIT1, UPS18, ISG15, ISG20, IFITM1, and OASL), chemokine signaling (CXCL10 and CXCL11), and adaptive immune system (IFITM1, CD300E, and SIGLEC1) genes in symptomatic, mild-to-moderate COVID-19 adults, when adjusting for age, sex, and race. Interestingly, the expression levels of most of these genes plateaued at a cycle threshold (CT) value of ~25. Overall, our data show that the early nasal mucosal immune response to SARS-CoV-2 infection is viral load dependent, potentially modifying COVID-19 outcomes. IMPORTANCE Several prior studies have shown that SARS-CoV-2 viral load can predict the likelihood of disease spread and severity. A higher detectable SARS-CoV-2 plasma viral load was associated with worse respiratory disease severity. However, the relationship between SARS-CoV-2 viral load, airway mucosal gene expression, and immune response remains elusive. We profiled the nasal mucosal transcriptome from nasal samples collected from adults infected with SARS-CoV-2 during spring 2020 with mild-to-moderate symptoms using a comprehensive metatranscriptomics method. We observed a positive correlation between SARS-CoV-2 viral load, interferon signaling, chemokine signaling, and adaptive immune system in adults with COVID-19. Our data suggest that early nasal mucosal immune response to SARS-CoV-2 infection was viral load dependent and may modify COVID-19 outcomes.

COVID-19 mass testing and sequencing: Experiences from a laboratory in Western Kenya.

Background: The Basic Science Laboratory (BSL) of the Kenya Medical Research Institute/Walter Reed Project in Kisumu, Kenya addressed mass testing challenges posed by the emergent coronavirus disease 2019 (COVID-19) in an environment of global supply shortages. Before COVID-19, the BSL had adequate resources for disease surveillance and was therefore designated as one of the testing centres for COVID-19. Intervention: By April 2020, the BSL had developed stringent safety procedures for receiving and mass testing potentially infectious nasal specimens. To accommodate increased demand, BSL personnel worked in units: nucleic acid extraction, polymerase chain reaction, and data and quality assurance checks. The BSL adopted procedures for tracking sample integrity and minimising cross-contamination. Lessons learnt: Between May 2020 and January 2022, the BSL tested 63 542 samples, of which 5375 (8.59%) were positive for COVID-19; 1034 genomes were generated by whole genome sequencing and deposited in the Global Initiative on Sharing All Influenza Data database to aid global tracking of viral lineages. At the height of the pandemic (August and November 2020, April and August 2021 and January 2022), the BSL was testing more than 500 samples daily, compared to 150 per month prior to COVID-19. An important lesson from the COVID-19 pandemic was the discovery of untapped resilience within BSL personnel that allowed adaptability when the situation demanded. Strict safety procedures and quality management that are often difficult to maintain became routine. Recommendations: A fundamental lesson to embrace is that there is no 'one-size-fits-all' approach and adaptability is the key to success.

Patient with Suspected COVID-19 Infection Tests Negative in Nasopharyngeal Swabs but is Confirmed by Laboratory Tests and Chest CT Scan: A Case Report

Chest CT imaging can be helpful in early diagnosis of COVID-19 instead of relying on real time polymerase chain reaction (RT-PCR) that can give false negative result. Nasopharyngeal samples from a 22 years old man were detected as negative for COVID-19 for consecutive three RT-PCR tests. Complete blood count (CBC), D-dimer, serum ferritin, eosinophil sedimentation rate (ESR) test, tuberculosis test, real time PCR and high-resolution computed tomography (HRCT) were done to rule out the cause of flu like symptoms. HRCT reveals a haze area in the right perihilar region adjacent to medial part of horizontal fissure on the 3rd day of manifestation of symptoms. Radiological studies showed early consolidation of COVID-19 whereas RT-PCR showed negative results. Chest CT imaging is a highly sensitive technique that has also been used in detection of corona virus. This case study emphasizes the importance of HRCT for early and confirm diagnosis of COVID-19 whereas RT-PCR results can vary. This process may show negative results and is time consuming. Copyright 2023 by the authors. Licensee Zoological Society of Pakistan.

The COVID-19 Pandemic Response System at University Level: The Case of Safe Campus Model at Ewha Womans University

In response to the changes in the Coronavirus disease 2019 (COVID-19) epidemic situation, Ewha Womans University established Ewha Safe Campus (ESC), an on-campus infection outbreak management system, to allow students and faculty members to safely resume face-to face classes in 2022. The COVID-19 testing station, Ewha Safe Station, is the core element of ESC. Symptomatic students and faculty members perform a combo swab self-PCR test or receive a nasopharyngeal swab PCR test from experts to prevent the spread of COVID-19 through early detection and management. ESC is significant in that it detects infection risks and proactively implements preemptive measures in a university. The COVID-19 health response system model at the university level was applied for the first time in South Korea, reaching a milestone in the history of university health in South Korea. In particular, it is highly valuable that the test was free of charge, as it enabled all of the examinees to have easy access to the test through joint cooperation with the Seegene Medical Foundation. This is a successful example of cooperation between schools and private institutions for public health improvement. In the future, the direct and indirect effects of the establishment and implementation of ESC need to be evaluated and confirmed, and areas requiring improvements need to be identified in preparation for another infectious disease outbreak in the future.

Omicron Wave SARS-CoV-2 Diagnosis: Evaluation of Saliva, Anterior Nasal, and Nasopharyngeal Swab Samples.

The Omicron variant differs from earlier strains of SARS-CoV-2 in the way it enters host cells and grows in vitro. We therefore reevaluated its diagnosis using saliva, nasopharyngeal swab (NPs), and anterior nasal swab (ANs) specimens from 202 individuals (64.9% symptomatic) tested at the Toulouse University Hospital SARS-CoV-2 drive-through testing center. All tests were done with the Thermo Fisher TaqPath COVID-19 reverse transcription-PCR (RT-PCR) kit. Overall, 92 subjects (45.5%) had one or more positive specimens. Global sensitivities of saliva, NPs, and ANs were 94.6%, 90.2%, and 82.6%, respectively. Saliva provided significantly greater sensitivity among symptomatic patients tested within 5 days of symptom onset (100%) than did ANs (83.1%) or NPs (89.8%). We obtained follow-up samples for 7/20 individuals with discordant results. Among them, 5 symptomatic patients were diagnosed positive on saliva sample only, soon after symptom onset; NPs and ANs became positive only later. Thus, saliva samples are effective tools for the detection of the Omicron variant. In addition to its many advantages, such as improved patient acceptance and reduced cost, saliva sampling could help limit viral spread through earlier viral detection. IMPORTANCE Diagnostic testing for SARS-CoV-2 is an essential component of the global strategy for the prevention and control of COVID-19. Since the beginning of the pandemic, numerous studies have evaluated the diagnostic sensitivity of different respiratory and oral specimens for SARS-CoV-2 detection. The pandemic has been since dominated by the emergence of new variants, the latest being the Omicron variant characterized by numerous mutations and changes in host tropism in vitro that might affect the diagnostic performance of tests depending on the sampling location. In this prospective study, we evaluated the clinical performance of NPs, ANs, and saliva for SARS-CoV-2 diagnosis during the Omicron wave. Our results highlight the effectiveness of saliva-based RT-PCR for the early detection of the Omicron variant. These findings may help to refine guidelines and support the use of a highly sensitive diagnostic method that allows earlier diagnosis, when transmission is the most critical.