Updated statistics on Influenza mortality

We have planned this analysis to provide current statistics on mortality directly caused by Influenza viruses in recent years in the US. We performed an electronic search in the online database CDC WONDER to obtain current statistics on direct mortality caused by Influenza viruses in the US. Mortality data are derived from information on all death certificates issued in the 50 states and the District of Columbia, excluding deaths of nonresidents. Our basic query criteria included Influenza-specific ICD-10 codes. Influenza caused an average of 7,670 deaths per year from 2018 to 2020 based on Influenza-specific ICD-10 codes, with a corresponding mean death rate of 2.3 × 100,000. The death rate increased in parallel with the age of the US resident population, from 0.2 × 100,000 in the 5-24 age group to 37.4 × 100,000 in US residents aged 85 years or older. No substantial differences were observed in males vs. females. The results of this analysis show that Influenza remains a significant clinical burden in the general population, with a cumulative mortality rate of approximately 2.3 × 100,000, but increasing more than tenfold (to over 37 × 100,000) in older persons.

Red blood cell distribution width (RDW) reflects disease severity in patients with carbon monoxide poisoning: systematic literature review and meta-analysis

No definitive prognostic biomarkers for carbon monoxide (CO) poisoning have been proposed. The aim of this study is to investigate, through a systematic literature review and pooled analysis, whether red blood cell distribution width (RDW) can predict disease severity in CO-poisoned patients. We performed an electronic search in Scopus and PubMed using the keywords: 'red blood cell distribution width' OR 'RDW' AND 'carbon monoxide' AND 'poisoning,' with no time or language restrictions (i.e. through August 2023) to find clinical studies that examined the value of RDW in patients with varying severity of CO poisoning. The analysis was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 reporting checklist. We identified 29 articles, seven of which were included in our analysis, with a total of 1979 CO-poisoned patients, 25.9% of whom were severely ill. In all but one of the studies, the RWD mean or median value was higher in CO-poisoned patients with severe disease. The weighted mean difference (WMD) of RDW was 0.36 (95% confidence interval (CI), 0.26-0.47)%. In the three articles in which the severity of illness in CO-poisoned patients was defined as cardiac injury, the WMD of the RDW was 1.26 (95%CI, 1.02-1.50)%. These results suggest that monitoring RDW in CO-poisoned patients may help to determine the severity of disease, particularly cardiac injury.

Short-Term Effect of Quetiapine Used to Treat Delirium Symptoms on Opioid and Benzodiazepine Requirements in the Pediatric Cardiac Intensive Care Unit

Opioids or benzodiazepines use is known to increase the risk of delirium. The prevalence of delirium is high in pediatric cardiac intensive care units (CICUs) with associated morbidity and mortality. We investigate the short-term effects of quetiapine, an atypical antipsychotic medication, on opioid and benzodiazepine requirements, and any associated adverse events as we utilize quetiapine to treat delirium symptoms in this single-center, retrospective study. Twenty-eight patients who received quetiapine between January 2018 and June 2019 in the CICU met inclusion criteria for the analysis. The quetiapine initiation dose was 0.5 mg/kg/dose every 8 h and we allowed 48 h for quetiapine to reach a steady state. Overall opioid and benzodiazepine requirements were compared 72 h before and 72 h after the quetiapine steady state. There was a statistically significant reduction in the total daily opioid (p = 0.001) and benzodiazepine (p = 0.01) amounts following quetiapine initiation. There was also a statistically significant decrease in the total number of daily PRNs requirement for both opioids (p < 0.001) and benzodiazepines (p = 0.03). Nine out of 13 patients were completely weaned off continuous opioid drips following quetiapine initiation (p = 0.01). The presence of steady-state habituation medications, including methadone or lorazepam, did not have any statistically significant effect on weaning continuous opioid (p = 0.18) or benzodiazepine (p = 0.62) drips. There was no statistically significant effect of quetiapine on the QTc interval after quetiapine initiation (p = 0.58) with no clinically significant arrhythmias observed during the study period. Our study demonstrates a statistically significant reduction in opioid and benzodiazepine requirements following quetiapine initiation to treat delirium symptoms without significant adverse effects in patients with congenital heart disease in the short term.

Analytical evaluation of the novel Mindray high sensitivity cardiac troponin I immunoassay on CL-1200i

OBJECTIVES

The current study was designed to evaluate the analytical performance of the new Mindray highly sensitive cardiac troponin I (hs-cTnI) chemiluminescent immunoassay on Mindray CL-1200i, as a thorough validation of novel hs-cTnI methods is required before introduction into clinical practice.

METHODS

The evaluation of the analytical performance of this hs-cTnI immunoassay encompassed the calculation of the limit of blank (LOB), limit of detection (LOD), functional sensitivity, imprecision, linearity, 99th percentile upper reference limit (URL) and concordance with another previously validated hs-cTnI chemiluminescent immunoassay.

RESULTS

The LOB and LOD were 0.32 and 0.35 ng/L, whilst the functional sensitivity (expressed as cTnI value with <10 % imprecision), was 0.35 ng/L. The linearity was excellent throughout a wide range of clinically measurable values (r=1.00 between 0.8 and 9,726.9 ng/mL). The intra-assay, inter-assay and total imprecision were 1.1-1.3 %, 5.5-8.1 % and 5.6-8.2 %, respectively. The 99th percentile URL calculated using residual plasma from 246 ostensibly healthy blood donors was 9.2 ng/L (4.3 ng/L in women vs. 12.3 ng/L in men). The Spearman's correlation between Mindray hs-cTnI and Access hs-TnI was 0.97, with mean bias of 7.2 % (95 % CI, 2.6-11.9 %).

CONCLUSIONS

Although we failed to confirm the very optimistic analytical characteristics previously reported for this method, our evaluation of the novel Mindray hs-cTnI immunoassay on CL-1200i demonstrated that the overall performance is comparable to that of other commercially available hs-cTnI techniques, making it a viable alternative to other methods.

Urine dipstick for screening plasma glucose and bilirubin in low resource settings: a proof-of-concept study

Objectives

The purpose of this proof-of-concept study was to investigate whether a commercially available urine dipstick may provide potentially useful information for screening plasma glucose and bilirubin in human plasma samples.

Methods

Glucose and bilirubin were assayed in 60 anonymized lithium-heparin residual plasma samples using the Roche COBAS 8000 or after pipetting 10 µL of plasma onto the pads of a commercial urine dipstick. Semiquantitative urine test results obtained with the dipstick were directly compared to paired test results obtained with COBAS.

Results

Median plasma glucose values between COBAS and dipstick were slightly different (5.8 vs. 5.6 mmol/L; p=0.040), while no significant difference was found in bilirubin values between COBAS and dipstick (11.2 vs. 8.6 μmol/L; p=0.090). The Spearman's correlation between COBAS and dipstick was 0.83 (95% CI, 0.73-0.90; p<0.001) for plasma glucose and 0.78 (95% CI, 0.66-0.87; p<0.001) for plasma bilirubin, respectively. Cumulative agreement between COBAS and dipstick was high for both glucose (88%; kappa statistic statistics, 0.75; 95% CI, 0.58-0.92; p<0.001) and bilirubin (88%; kappa statistics, 0.76; 95% CI, 0.60-0.92; p<0.001).

Conclusions

The results of this proof-of-concept study indicate that the commercial urine test strip used in our study provides acceptable performance for screening plasma glucose and bilirubin levels compared with reference laboratory assays.

Uso de una tira reactiva paraorina en la evaluación de las concentraciones de glucosa y bilirrubina en plasma en entornos con recursos limitados: un estudio de prueba de concepto

Objetivos

El objetivo del presente estudio de prueba de concepto, era investigar si una tira reactiva comercial para orina aporta información potencialmente útil para la evaluación de glucosa y bilirrubina en muestras de plasma humano.

Métodos

Se determinaron las concentraciones de glucosa y bilirrubina en 60 muestras anonimizadas de plasma residual de heparina de litio, en un analizador Roche COBAS 8000 y en la tira reactiva comercial para orina, tras pipetear 10 µL de plasma, en las almohadillas que ésta incorpora. Se llevó a cabo una comparación directa entre los resultados semicuantitativos de la tira reactiva y los de las muestras pareadas obtenidos con el analizador COBAS.

Resultados

Se observaron leves diferencias entre el analizador COBAS y la tira reactiva en relación a la mediana de la concentración de glucosa (5,8 frente a 5,6 mmol/L, respectivamente; p=0,040). Por otro lado, no se observaron diferencias estadísticamente significativas en los valores de bilirrubina entre COBAS y la tira reactiva (11,2 frente a 8,6 μmol/L; p=0,090). El coeficiente de correlación de Spearman entre COBAS y la tira reactiva fue de 0,83 (IC 95 %, 0,73–0,90; p<0,001) para la glucosa en plasma, y 0,78 (IC 95 %, 0,66–0,87; p<0,001) para la bilirrubina en plasma. La concordancia acumulada entre COBAS y la tira reactiva fue alta tanto para la glucosa (88 %; coeficiente kappa, 0.75; IC 95 %, 0,58–0,92; p<0,001) como para la bilirrubina (88 %; coeficiente kappa, 0,76; IC 95 %, 0,60–0.92; p<0,001).

Conclusiones

Los resultados del estudio de prueba de concepto indican que la tira reactiva comercial para orina de nuestro estudio posee un rendimiento aceptable en la determinación de las concentraciones de glucosa y bilirrubina en plasma, en comparación con las pruebas analíticas de referencia.

Disruption of laboratory activities during the COVID-19 pandemic: results of an EFLM Task Force Preparation of Labs for Emergencies (TF-PLE) survey

Background

The EFLM Task Force Preparation of Labs for Emergencies (TF-PLE) created a survey that has been distributed to its members for gathering information on the key hazards experienced by European medical laboratories during the COVID-19 pandemic.

Methods

The survey was distributed to over 12,000 potential contacts (laboratory workers) via an EFLM newsletter, with responses collected between May 8 and June 8, 2023.

Results

Two hundred replies were collected and examined from European laboratories. 69.7% and 78.1% of all responders said they were short on non-COVID and COVID reagents, respectively. Exactly half of respondents (50.0%) said that they could not complete all laboratory tests required for a specific period, but this figure climbed to 61.2% for COVID tests. Finally, 72.3% of respondents expressed exhaustion during the pandemic, and 61.2% reported increasing patient hostility.

Conclusions

The COVID-19 pandemic had a significant impact on laboratory medicine in Europe. Cultural change, proactive planning, and even re-engineering in some parts of the laboratory industry may thus be necessary to prepare for future challenges.

Safety monitoring of drug-induced muscle injury and rhabdomyolysis: a biomarker-guided approach for clinical practice and drug trials

Skeletal muscle tissue (SKM) may be damaged due to mechanical, metabolic, and exertional causes. However, drug-induced myopathy is among the most frequent causes of muscle disease. The clinical picture of drug-induced myopathies may be highly variable. It may present as asymptomatic or mild myalgias, with or without muscle weakness, which are likely underreported. However, it may also appear as chronic myopathy with severe weakness and, rarely, even as massive rhabdomyolysis with acute kidney injury (AKI). Unfortunately, the available biomarkers for SKM injury do not fully meet the needs for satisfactory detection of drug-induced damage, both in clinical and research settings, mainly due to their low sensitivity and specificity. Therefore, the present study proposes a strategy for drug safety monitoring using the available biomarkers of SKM injury. Moreover, we will discuss mechanisms of drug-induced SKM injury, traditional laboratory testing for SKM injury, and novel skeletal myocyte biomarkers under investigation. This can be incredibly useful in both clinical practice and for de-challenge/re-challenge investigational trials where the risk of drug-induced SKM injury is present.

Clinical assessment of SNIBE Maglumi SARS-CoV-2 antigen fully-automated chemiluminescent immunoassay

OBJECTIVES

Given that SARS-CoV-2 antigen tests will represent a pillar for supporting or surrogating molecular testing in the endemic period, we report here the clinical performance of the new SNIBE Maglumi SARS-CoV-2 antigen fully-automated chemiluminescent immunoassay (MAG-CLIA SARS-CoV-2 Ag).

METHODS

The study population consisted of 181 subjects (mean age 61 ± 21 years; 92 females) undergoing coronavirus disease 2019 (COVID-19) testing at the local diagnostic facility, from December 2022 to February 2023. Routine diagnostic practice involved the collection of a double nostril nasopharyngeal swab, analyzed in duplicate with SARS-CoV-2 antigen (MAG-CLIA SARS-CoV-2 Ag) and molecular (Altona Diagnostics RealStar SARS-CoV-2 RT-PCR Kit) tests.

RESULTS

A significant Spearman's correlation was found between MAG-CLIA SARS-CoV-2 Ag and mean Ct values of SARS-CoV-2 E and S genes (r=-0.95; p<0.001). In all nasopharyngeal samples, the area under the curve (AUC) of MAG-CLIA SARS-CoV-2 Ag was 0.86 (95% CI, 0.81-0.90), with 0.71 sensitivity and 1.00 specificity at 7 ng/L cut-off, increasing to 0.98 (95% CI, 0.96-1.00) AUC and 0.96 sensitivity (with 0.97 specificity) in high viral load samples. When SARS-CoV-2 N protein concentration was replaced with raw instrumental readings (i.e., relative light units [RLU]), the AUC in all samples increased to 0.94. A RLU value of 945 was associated with 88.4% accuracy, 0.85 sensitivity, 0.95 specificity, 0.77 negative predictive value (NPV) and 0.97 positive predictive value (PPV), respectively.

CONCLUSIONS

We found satisfactory analytical performance of MAG-CLIA SARS-CoV-2 Ag, which could be used as surrogate of molecular testing for identifying high viral load samples. Broadening the reportable range of values may generate even better performance.

Topographic anatomy of the submental artery and its clinical implications for reconstructive surgery

Knowledge about the anatomy of the submental artery (SA) is of immense importance when performing plastic and reconstructive procedures. A retrospective study was performed to analyze the topographic anatomy of the SA. The measurements were performed on 80 consecutive patients who underwent head and neck computed tomography angiography (CTA). The SA was present in 131 out of 137 hemifaces (95.6%). The vessel originated from the facial artery in all cases (100.0%). Moreover, the SA was found to have 0-4 branches. However, most commonly, the said artery had no branches of considerable size (51.1%). Due to the high variability of the course of the said artery, the authors of the present study created a novel classification system presenting the most prevalent courses of the SA in the submental region. The current study utilized 131 hemifaces of 80 (CTA) to create a heat map of the SA, illustrating its precise origin and course in the submental region. The findings of this study could assist surgeons in developing a mental map of the arterial anatomy of the submental region, potentially improving the efficiency of localizing the SA and reducing the risk of complications during plastic and reconstructive procedures.

Pooled analysis of diagnostic performance of the instrument-read Quidel Sofia SARS antigen Fluorescent Immunoassay (FIA)

Background

This article presents a critical literature review and meta-analysis of diagnostic performance of Quidel Sofia SARS antigen Fluorescent Immunoassay (FIA), a rapid diagnostic antigen test (RDT-Ag) adapted for automatic reading with portable instruments, thus potentially combining the advantages of point-of-care testing with those of a laboratory-based immunoassay.

Methods

We conducted an electronic search in PubMed and Scopus with the keywords "Quidel" OR "SOFIA" AND "Antigen" AND "SARS-CoV-2" OR "COVID-19" up to March 24, 2023, for identifying articles containing data on accuracy of Quidel Sofia SARS antigen FIA for diagnosing acute SARS-CoV-2 infections. We selected those where test accuracy was compared to that of a reference SARS-CoV-2 molecular assay, and with sufficient information for constructing a 2×2 table.

Results

A total number of 18 articles (48165 samples; 9.8% positive at molecular testing) were included in this meta-analysis, averaging 24 sample cohorts. The diagnostic accuracy (summary area under the curve), sensitivity and specificity were 0.980, 0.76 and 1.00 in all samples, 0.981, 0.81 and 0.99 in samples collected from symptomatic patients, 0.931, 0.55 and 1.00 in those taken from asymptomatic patients, and 0.960, 0.77 and 0.99 in samples from mixed cohorts of patients, respectively. Minor and clinically negligible differences of accuracy could be found by comparing test results in nasal and nasopharyngeal swabs.

Conclusion

Quidel Sofia SARS Ag FIA meets the minimum performance criteria of accuracy for SARS-CoV-2 antigenic testing, thus combining satisfactory diagnostic performance with the advantages of being potentially used as a portable device.

Assessment of humoral and cellular immunity after bivalent BNT162b2 vaccination and potential association with reactogenicity

OBJECTIVES

This study investigated the feasibility and clinical value of using a novel, automated and high-throughput SARS-CoV-2 Interferon Gamma Release Assay (IGRA), combined with total anti-SARS-CoV-2 antibodies assessment, for evaluating the immune response after bivalent BNT162b2 vaccination.

METHODS

A cohort of healthcare workers, who already underwent primary vaccination and boosting with monovalent BNT162b2 vaccine, received a booster dose of the new BNT162b2 bivalent formulation. Blood samples were taken immediately before vaccination (T0) and 1 month afterwards (T1). Humoral and cellular immunity were assayed with Roche Elecsys Anti-SARS-CoV-2 and Roche Elecsys IGRA SARS-CoV-2, respectively.

RESULTS

The study population consisted of 51 subjects (median age: 43 years; 51% females). Total anti-SARS-CoV-2 antibodies and IGRA SARS-CoV-2 values increased at T1 from 9,050 to 25,000 BAU/mL (p<0.001), and from 0.44 to 0.78 IU/mL (p=0.385), accounting for median increase of 2.0 and 1.6 folds, respectively. Increased T1 values of total anti-SARS-CoV-2 antibodies and IGRA SARS-CoV-2 were recorded in 100% and 68.6% subjects, respectively. In those with baseline values below the median, post-vaccine levels displayed larger increases of 3.3 and 5.1 folds for anti-SARS-CoV-2 total antibodies and IGRA SARS-CoV-2, respectively. The variation of total anti-SARS-CoV-2 antibodies was inversely associated with their T0 values (r=-0.97; p<0.001), whilst that of IGRA SARS-CoV-2 was inversely associated with its T0 value (r=-0.58; p<0.001). No other signifcant associations were found with demographical or clinical variables, including side effects.

CONCLUSIONS

The bivalent BNT162b2 vaccine booster enhances humoral and cellular immunity against SARS-CoV-2, especially in recipients with lower baseline biological protection.

Diagnostic accuracy of Siemens SARS-CoV-2 Antigen (CoV2Ag) chemiluminescent immunoassay for diagnosing acute SARS-CoV-2 infection: a pooled analysis

BACKGROUND

This article provides a critical literature review and pooled analysis of diagnostic accuracy of the fully-automated Siemens SARS-CoV-2 Antigen (CoV2Ag) chemiluminescent immunoassay for diagnosis of acute SARS-CoV-2 infections.

METHODS

An electronic search was conducted in Scopus, PubMed and medRxiv using the keywords ["Siemens AND CoV2Ag"] OR ["Siemens AND SARS-CoV-2 AND antigen"] for capturing studies that investigated the accuracy of Siemens CoV2Ag for diagnosing acute SARS-CoV-2 infection against a reference SARS-CoV-2 molecular test. The retrieved information was used for constructing a 2 × 2 table and for calculating pooled diagnostic sensitivity, specificity, Summary Receiver Operating Characteristic Curve (SROC) and Agreement. This study followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) reporting checklist.

RESULTS

Four studies totalling 1,310 respiratory samples (612 with high viral load) were finally included in our analysis. The cumulative area under the curve, accuracy, sensitivity, specificity, were 0.964 (95% CI, 0.957-0.971), 86.9% (95% CI, 84.9-88.7%), 0.79 (95% CI, 0.76-0.82) and 0.98 (95% CI, 0.96-0.99), respectively. The negative (NPV) and positive (PPV) predictive values were 0.77 (0.74-0.79) and 0.98 (95% CI, 0.96-99), respectively. The diagnostic sensitivity in samples with high viral load (i.e., Ct<29-30) was 0.95 (95% CI, 0.93-0.97).

CONCLUSIONS

The Siemens CoV2Ag fully-automated and high-throughput immunoassay approximates the minimum performance criteria for general SARS-CoV-2 antigen testing and displays excellent performance in samples with high viral load, thus representing a valuable screening solution for risk assessment in COVID-19 and for limiting viral spread.

Are anti-SARS-CoV-2 S/N IgG/IgM antibodies always predictive of previous SARS-CoV-2 infection?

Objectives

We planned this study to verify whether immunoassays for quantifying anti-SARS-CoV-2 IgG/IgM antibodies against both spike (S) and nucleocapsid (N) proteins may be used for identifying previous SARS-CoV-2 infections.

Methods

The study population consisted of a cohort of fully vaccinated healthcare workers. All study subjects underwent regular medical visits and molecular testing for diagnosing SARS-CoV-2 infections every 2-4 weeks between 2020-2022. Venous blood was drawn for measuring anti-SARS-CoV-2 antibodies with MAGLUMI 2019-nCoV lgG/IgM CLIA Assays directed against both SARS-CoV-2 S and N proteins.

Results

Overall, 31/53 (58.5%) subjects had tested positive for SARS-CoV-2 by RT-PCR throughout the study (24 once, 7 twice). No positive correlation was found between anti-SARS-CoV-2 S/N IgM antibodies and molecular test positivity. In univariate regression analysis, both a molecular test positivity (r=0.33; p=0.015) and the number of positive molecular tests (r=0.43; p=0.001), but not vaccine doses (r=-0.12; p=0.392), were significantly correlated with anti-SARS-CoV-2 S/N IgG antibodies. These two associations remained significant in multiple linear regression analysis (p=0.029 and p<0.001, respectively) after adjusting for sex, age, body mass index, and vaccine doses. In ROC curve analysis, anti-SARS-CoV-2 S/N IgG antibodies significantly predicted molecular test positivity (AUC, 0.69; 95% CI; 0.55-0.84), with the best cutoff of 0.05 AU/mL displaying 67.9% accuracy, 0.97 sensitivity, and 0.27 specificity.

Conclusions

Although anti-SARS-CoV-2 S/N IgG antibodies provide helpful information for identifying previous SARS-CoV-2 infections, a lower cutoff than that of sample reactivity should be used. Anti-SARS-CoV-2 S/N IgM antibodies using conventional cutoffs seem useless for this purpose.

Real-world assessment of the clinical performance of COVID-VIRO ALL IN rapid SARS-CoV-2 antigen test

OBJECTIVES

Since the external validation of severe acute respiratory syndrome coronavirus 2 antigen rapid diagnostic tests (SARS-CoV-2 RDT-Ags) is a necessary requisite before they can be introduced into routine clinical practice, this study reports the results of a real-world assessment of the clinical performance of the new COVID-VIRO ALL IN device.

METHODS

The study population consisted in 165 outpatients (median age: 43 years, range: 14-68 years; 66.1% females) who had paired nasal and nasopharyngeal samples collected upon hospital presentation. The samples were concomitantly tested with the AAZ-LMB COVID-VIRO ALL IN SARS-CoV-2 RDT-Ag and with Cepheid Xpert Xpress SARS-CoV-2 real-time reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

The number of subjects with positive RT-PCR results (i.e., mean Ct value <45) was 116 (70.3%), 109 (66.1%) and 86 (52.1%) with mean Ct values <37 and <30, respectively. In all RT-PCR positive samples, COVID-VIRO ALL IN displayed 78.8% agreement, 0.698 sensitivity, 1.000 specificity, 0.583 negative predictive value (NPV) and 1.000 positive predictive value (PPV) compared to RT-PCR. The median Ct value of samples testing positive with COVID-VIRO ALL IN was significantly lower than those testing negative (22.8 vs. 32.2; p<0.001). In samples with high viral load (i.e., Ct value <30), COVID-VIRO ALL IN displayed 92.1% agreement, 0.895 sensitivity, 0.949 specificity, 0.983 NPV and 0.951 PPV compared to RT-PCR.

CONCLUSIONS

Although the diagnostic performance of COVID-VIRO ALL IN do not exactly match those of the manufacturer, its high NPV in high viral load samples would enable fast-track and rapid identification of highly contagious subjects.

Correlation between relative age-standardized mortality rates and COVID-19 mortality over time in Italy

BACKGROUND AND AIM

This study was planned to estimate the contribution of coronavirus disease 2019 (COVID-19) related mortality on excess deaths recorded in Italy since the beginning of the pandemic.

METHODS

Official data on weekly number of COVID-19 related deaths in Italy were retrieved from the website of the Italian Ministry of Health, whilst information on weekly relative age-standardised mortality rates (rASMRs) in Italy during the COVID-19 pandemic was downloaded from the UK Office for National Statistics website. Univariate and multivariate correlation was conducted to explore the association between these two variables throughout the pandemic.

RESULTS

Significant univariate correlation was found between rASMR and number of official COVID-19 related deaths throughout the pandemic period. Such correlation was especially high during predominance of pre-Alpha and Alpha variants, remained significant during Delta variant predominance, but become no longer significant during Omicron variant predominance. In multivariable analysis, we estimated that COVID-19 may have contributed to 72% of the excess mortality recorded in Italy throughout the pandemic. The impact was higher during pre-Alpha and Alpha periods (i.e., 78% and 89%, respectively), decreased to 41% during Delta variant predominance, and became no longer significant after emergence of the Omicron variant.

CONCLUSIONS

These results would suggest that COVID-19 may have largely contributed to excess mortality in Italy until the recent emergence of the Omicron variant, by which time previous loss of vulnerable people and radical changes in delivering healthcare may have paradoxically contributed to improve the cumulative death rate in the country.

COVID-19 and its long-term sequelae: what do we know in 2023?

Post‑viral syndrome is a well‑known medical condition characterized by different levels of physical, cognitive, and emotional impairment that may persist with fluctuating severity after recovering from an acute viral infection. Unsurprisingly, COVID‑19 may also be accompanied by medium- and long‑term clinical sequelae after recovering from a SARS‑CoV‑2 infection. Although many clinical definitions have been provided, "long‑COVID" can be defined as a condition occurring in patients with a history of SARS‑CoV‑2 infection, developing 3 months from the symptoms onset, persisting for at least 2 months, and not explained by alternative diagnoses. According to recent global analyses, the cumulative prevalence of long‑COVID seems to range between 9% and 63%, and is up to 6‑fold higher than that of similar postviral infection conditions. Long‑COVID primarily encompasses the presence of at least 1 symptom, such as fatigue, dyspnea, cognitive impairment / brain fog, postexertional malaise, memory issues, musculoskeletal pain / spasms, cough, sleep disturbances, tachycardia / palpitations, altered smell / taste perception, headache, chest pain, and depression. The most important demographic and clinical predictors to date are female sex, older age, cigarette smoking, pre‑existing medical conditions, lack of COVID‑19 vaccination, infection with pre‑Omicron SARS‑CoV‑2 variants, number of acute phase symptoms, viral load, severe / critical COVID‑19 illness, as well as invasive mechanical ventilation. Concerning the care for long‑COVID patients, the greatest challenge is the fact that this syndrome cannot be considered a single clinical entity, and thus it needs an integrated multidisciplinary management, specifically tailored to the type and severity of symptoms.

Estimating the worldwide burden of health loss due to hearing loss

We planned this study to define the worldwide burden of health loss attributed to hearing impairment occurred during the past 10 years according to the 2019 Global Health Data Exchange (GHDx) database. The current worldwide burden of health loss due to all forms of hearing impairment is estimated at 43.4 million Years Lived with Disability (YLDs), representing 28% of cumulative YLDs due to all physical impairments in GHDx. The hearing loss-attributable YLDs have linearly increased (r = 0.997; P < 0.01) by 18.7% during the past 10 years. Reinforced policies are hence needed for preventing development of mild hearing impairment and/or progression toward more severe deficiencies.

Positivization time of a COVID-19 rapid antigen self-test predicts SARS-CoV-2 viral load: a proof of concept

OBJECTIVES

This proof of concept study was aimed to validate the hypothesis that the time of positivization of SARS-CoV-2 self-performed rapid diagnostic tests (RDTs) may reflect the actual viral load in the specimen.

METHODS

A SARS-CoV-2 positive sample with high viral load was diluted and concomitantly assayed with molecular assay (Xpert Xpress SARS-CoV-2) and RDT (COVID-VIRO ALL IN RDT). The (mean cycle threshold; Ct) values and RDT positivization times of these dilutions were plotted and interpolated by calculating the best fit. The parameters of this equation were then used for converting the positivization times into RDT-estimated SARS-CoV-2 Ct values in routine patient samples.

RESULTS

The best fit between measured and RDT-estimated Ct values could be achieved with a 2-degree polynomial curve. The RDT-estimated Ct values exhibited high correlation (r=0.996) and excellent Deming fit (y=1.01 × x - 0.18) with measured Ct values. In 30 consecutive patients with positive RDT test, the correlation between RDT positivization time and measured Ct value was r=0.522 (p=0.003). The correlation of RDT-estimated and measured Ct values slightly improved to 0.577 (Deming fit: y=0.44 × x + 11.08), displaying a negligible bias (1.0; 95% CI, -0.2 to 2.2; p=0.105). Concordance of RDT-estimated and measured Ct values at the <20 cut-off was 80%, with 0.84 sensitivity and 0.73 specificity.

CONCLUSIONS

This proof of concept study demonstrates the potential feasibility of using RDTs for garnering information on viral load in patients with acute SARS-CoV-2 infection.

An overview of the most important preanalytical factors influencing the clinical performance of SARS-CoV-2 antigen rapid diagnostic tests (Ag-RDTs)

Due to the many technical limitations of molecular biology, the possibility to sustain enormous volumes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnostic testing relies strongly on the use of antigen rapid diagnostic tests (Ag-RDTs). Besides a limited analytical sensitivity, the manually intensive test procedures needed for performing these tests, very often performed by unskilled personnel or by the patients themselves, may contribute to considerably impair their diagnostic accuracy. We provide here an updated overview on the leading preanalytical drawbacks that may impair SARS-CoV-2 Ag-RDT accuracy, and which encompass lower diagnostic sensitivity in certain age groups, in asymptomatic subjects and those with a longer time from symptoms onset, in vaccine recipients, in individuals not appropriately trained to their usage, in those recently using oral or nasal virucidal agents, in oropharyngeal swabs and saliva, as well as in circumstances when instructions provided by the manufacturers are unclear, incomplete or scarcely readable and intelligible. Acknowledging these important preanalytical limitations will lead the way to a better, more clinically efficient and even safer use of this important technology, which represents an extremely valuable resource for management of the ongoing pandemic.

Deciphering the role of monocyte and monocyte distribution width (MDW) in COVID-19: an updated systematic review and meta-analysis

The SARS-CoV-2 infection is characterized by both systemic and organ hyper-thromboinflammation, with a clinical course ranging from mild up-to critical systemic dysfunction and death. In patients with coronavirus disease 2019 (COVID-19) the monocyte/macrophage population is deeply involved as both trigger and target, assuming the value of useful diagnostic/prognostic marker of innate cellular immunity. Several studies correlated morphological and immunophenotypic alterations of circulating monocytes with clinical outcomes in COVID-19 patients, concluding that monocyte distribution width (MDW) may retain clinical value in stratifying the risk of disease worsening. Through an electronic search in Medline and Scopus we performed an updated literature review and meta-analysis aimed to explore the association between increased MDW levels and illness severity in COVID-19 patients, deciphering role(s) and function(s) of monocytes in the harmful network underlining SARS-CoV-2 infection. We found that significantly elevated MDW values were frequently present in COVID-19 patients who developed unfavorable clinical outcomes, compounded by a significant association between monocyte anisocytosis and SARS-CoV-2 outcomes. These findings suggest that blood MDW index and its scatter plot could represent useful routine laboratory tools for early identification of patients at higher risk of unfavorable COVID-19 and for monitoring the progression of viral infection, clinical outcomes, and therapeutic efficacy throughout hospitalization. According to this evidence, therapeutic decisions in patients with SARS-CoV-2 infection could benefit from monitoring MDW value, with administration of drugs limiting thrombo-inflammation due to monocyte hyper-activation in patients with severe/critical COVID-19 disease.

A Simple Epidemiologic Model for Predicting Impaired Neutralization of New SARS-CoV-2 Variants

This study is aimed at developing a simple epidemiologic model that could help predict the impaired neutralization of new SARS-CoV-2 variants. We explored the potential association between neutralization of recent and more prevalent SARS-CoV-2 sublineages belonging to the Omicron family (i.e., BA.4/5, BA.4.6, BA.2.75.2, BQ.1.1 and XBB.1) expressed as FFRNT50 (>50% suppression of fluorescent foci fluorescent focus reduction neutralization test) in recipients of four doses of monovalent mRNA-based coronavirus disease 2019 (COVID-19) vaccines, with epidemiologic variables like emergence date and number of spike protein mutations of these sublineages, cumulative worldwide COVID-19 cases and cumulative number of COVID-19 vaccine doses administered worldwide at the time of SARS-CoV-2 Omicron sublineage emergence. In the univariate analysis, the FFRNT50 value for the different SARS-CoV-2 Omicron sublineages was significantly associated with all such variables except with the number of spike protein mutations. Such associations were confirmed in the multivariate analysis, which enabled the construction of the equation: “−0.3917 × [Emergence (date)] + 1.403 × [COVID-19 cases (million)] − 121.8 × [COVID-19 Vaccine doses (billion)] + 18,250”, predicting the FFRNT50 value of the five SARS-CoV-2 Omicron sublineages with 0.996 accuracy (p = 0.013). We have shown in this work that a simple mathematical approach, encompassing a limited number of widely available epidemiologic variables, such as emergence date of new variants and number of COVID-19 cases and vaccinations, could help identifying the emergence and surge of future lineages with major propensity to impair humoral immunity.

Mitigation of SARS-CoV-2 by Using Transition Metal Nanozeolites and Quaternary Ammonium Compounds as Antiviral Agents in Suspensions and Soft Fabric Materials

Introduction

The coronavirus disease 2019 (COVID-19) pandemic has demonstrated the need for novel, affordable, and efficient reagents to help reduce viral transmission, especially in high-risk environments including medical treatment facilities, close quarters, and austere settings. We examined transition-metal nanozeolite suspensions and quaternary ammonium compounds as an antiviral surface coating for various textile materials.

Methods

Zeolites are crystalline porous aluminosilicate materials, with the ability of ion-exchanging different cations. Nanozeolites (30 nm) were synthesized and then ion-exchanged with silver, zinc and copper ions. Benzalkonium nitrate (BZN) was examined as the quaternary ammonium ion (quat). Suspensions of these materials were tested for antiviral activity towards SARS-CoV-2 using plaque assay and immunostaining. Suspensions of the nanozeolite and quat were deposited on polyester and cotton fabrics and the ability of these textiles towards neutralizing SARS-CoV-2 was examined.

Results

We hypothesized that transition metal ion containing zeolites, particularly silver and zinc (AM30) and silver and copper (AV30), would be effective in reducing the infectivity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Additionally, AM30 and AV30 antiviral potency was tested when combined with a quaternary ammonium carrier, BZN. Our results indicate that exposure of SARS-CoV-2 to AM30 and/or AV30 suspensions reduced viral loads with time and exhibited dose-dependence. Antiviral activities of the combination of zeolite and BZN compositions were significantly enhanced. When used in textiles, AM30 and AV30-coated cotton and polyester fabrics alone or in combination with BZN exhibited significant antiviral properties, which were maintained even after various stress tests, including washes, SARS-CoV-2-repeated exposures, or treatments with soil-like materials.

Conclusion

This study shows the efficacy of transition metal nanozeolite formulations as novel antiviral agents and establishes that nanozeolite with silver and zinc ions (AM30) and nanozeolite with silver and copper ions (AV30) when combined with benzalkonium nitrate (BZN) quickly and continuously inactivate SARS-CoV-2 in suspension and on fabric materials.

In silico evaluation of the impact of Omicron variant of concern sublineage BA.4 and BA.5 on the sensitivity of RT-qPCR assays for SARS-CoV-2 detection using whole genome sequencing

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant of concern (VoC) Omicron (B.1.1.529) has rapidly spread around the world, presenting a new threat to global public human health. Due to the large number of mutations accumulated by SARS-CoV-2 Omicron, concerns have emerged over potentially reduced diagnostic accuracy of reverse-transcription polymerase chain reaction (RT-qPCR), the gold standard diagnostic test for diagnosing coronavirus disease 2019 (COVID-19). Thus, we aimed to assess the impact of the currently endemic Omicron sublineages BA.4 and BA.5 on the integrity and sensitivity of RT-qPCR assays used for coronavirus disease 2019 (COVID-19) diagnosis via in silico analysis. We employed whole genome sequencing data and evaluated the potential for false negatives or test failure due to mismatches between primers/probes and the Omicron VoC viral genome.

METHODS

In silico sensitivity of 12 RT-qPCR tests (containing 30 primers and probe sets) developed for detection of SARS-CoV-2 reported by the World Health Organization (WHO) or available in the literature, was assessed for specifically detecting SARS-CoV-2 Omicron BA.4 and BA.5 sublineages, obtained after removing redundancy from publicly available genomes from National Center for Biotechnology Information (NCBI) and Global Initiative on Sharing Avian Influenza Data (GISAID) databases. Mismatches between amplicon regions of SARS-CoV-2 Omicron VoC and primers and probe sets were evaluated, and clustering analysis of corresponding amplicon sequences was carried out.

RESULTS

From the 1164 representative SARS-CoV-2 Omicron VoC BA.4 sublineage genomes analyzed, a substitution in the first five nucleotides (C to T) of the amplicon's 3'-end was observed in all samples resulting in 0% sensitivity for assays HKUnivRdRp/Hel (mismatch in reverse primer) and CoremCharite N (mismatch in both forward and reverse primers). Due to a mismatch in the forward primer's 5'-end (3-nucleotide substitution, GGG to AAC), the sensitivity of the ChinaCDC N assay was at 0.69%. The 10 nucleotide mismatches in the reverse primer resulted in 0.09% sensitivity for Omicron sublineage BA.4 for Thai N assay. Of the 1926 BA.5 sublineage genomes, HKUnivRdRp/Hel assay also had 0% sensitivity. A sensitivity of 3.06% was observed for the ChinaCDC N assay because of a mismatch in the forward primer's 5'-end (3-nucleotide substitution, GGG to AAC). Similarly, due to the 10 nucleotide mismatches in the reverse primer, the Thai N assay's sensitivity was low at 0.21% for sublineage BA.5. Further, eight assays for BA.4 sublineage retained high sensitivity (more than 97%) and 9 assays for BA.5 sublineage retained more than 99% sensitivity.

CONCLUSION

We observed four assays (HKUnivRdRp/Hel, ChinaCDC N, Thai N, CoremCharite N) that could potentially result in false negative results for SARS-CoV-2 Omicron VoCs BA.4 and BA.5 sublineages. Interestingly, CoremCharite N had 0% sensitivity for Omicron Voc BA.4 but 99.53% sensitivity for BA.5. In addition, 66.67% of the assays for BA.4 sublineage and 75% of the assays for BA.5 sublineage retained high sensitivity. Further, amplicon clustering and additional substitution analysis along with sensitivity analysis could be used for the modification and development of RT-qPCR assays for detecting SARS-CoV-2 Omicron VoC sublineages.

Correlation Between Time to Positive Result of SARS-CoV-2 Rapid Antigen Self-Test and Viral Antigen Concentration

Background

This study was planned to investigate how the positivization time of a SARS-CoV-2 rapid antigen self-test may correlate with SARS-CoV-2 nucleocapsid (N) antigen concentration measured with a quantitative laboratory-based immunoassay.

Methods

Paired nasopharyngeal (healthcare-collected) and nasal (self-collected) samples were taken from patients undergoing routine SARS-CoV-2 testing. The concentration of SARS-CoV-2 antigen nucleocapsid (N) was assayed with Liaison SARS-CoV-2 Antigen test, whilst the time of positivization of COVID-VIRO ALL rapid diagnostic test (RDT) was concomitantly measured and then compared SARS-CoV-2 viral load measured with Liaison SARS-CoV-2 Antigen test and expressed as Median Tissue Culture Infectious Dose (TCID50)/mL.

Results

The study sample consisted of 32 paired specimens which tested positive with COVID-VIRO ALL IN RDT and had SARS-CoV-2 N protein concentration measured with Liaison SARS-CoV-2 Antigen test. A highly significant correlation was found between SARS-CoV-2 viral antigen concentration and RDT positivization time (r=-0.64; 95%CI, -0.81 to -0.38; p<0.001). At the >1500 TCID50/mL threshold of the Liaison SARS-CoV-2 Antigen test, the positivization time of the COVID-VIRO ALL IN RDT displayed high accuracy (93.7%). A positivization time <42 sec enabled to identify patients with high SARS-CoV-2 antigen concentration (i.e., >1500 TCID50/mL) with 91.3% negative and 100% positive predictive values.

Conclusion

Self-testing using COVID-VIRO ALL IN RDT could be reliably used for garnering valuable information on the actual SARS-CoV-2 viral antigen concentration in respiratory samples.

Clinical performance of Fujirebio Lumipulse G SARSCoV- 2 Ag chemiluminescent immunoassay

We evaluated the performance of Fujirebio Lumipulse G SARS-CoV-2 Ag chemiluminescent immunoassay. A nasopharyngeal swab was collected from 160 subjects and assayed simultaneously with Fujirebio Lumipulse G SARS-CoV-2 Ag and Altona Diagnostics RealStar SARS-CoV-2 RT-PCR assays. Using 0.60 pg/mL diagnostic threshold, Fujirebio Lumipulse G SARS-CoV-2 Ag displayed 0.88 area under the curve, 0.88 sensitivity and 0.75 specificity compared to molecular testing. The area under the curve increased to 1.00 after excluding samples with low viral load (i.e., cycle threshold values between 25-37). Thus, this chemiluminescent immunoassay could be used for rapid identification of many subjects with high nasopharyngeal SARS-CoV-2 viral load.

Evolution of throat symptoms during the COVID-19 pandemic in the US

OBJECTIVES

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) structure and host tropism have changed over time, and so has the involvement of throat structures. This infodemiological analysis is hence aimed at investigating the evolution of throat symptoms during the COVID-19 pandemic in the US.

METHODS

We searched Google Trends using the medical search terms "ageusia", "hoarseness", "dysphonia", "pharyngitis" and "laryngitis", setting geographical location to "United States", within the past 5 years. The weekly Google Trends score for these symptoms, which reflects their national Web popularity, was divided in three parts, as "pre-COVID" (July 2017 to February 2020), COVID-19 "pre-Omicron" (March 2020 to November 2021), and COVID-19 "Omicron" (December 2021 to July 2022), and then compared.

RESULTS

The volume of searches for ageusia increased in the pre-Omicron period and remained significantly higher also during Omicron prevalence, though a significant decrease (∼30%) occurred with Omicron lineages compared to previous strains. The Google searches for hoarseness and dysphonia were relatively similar between the pre-COVID and pre-Omicron periods, but then significantly increased during Omicron predominance. The Google searches for pharyngitis and laryngitis decreased in the pre-Omicron period, but then considerably increased following Omicron emergence. Omicron endemic spread could be significantly and independently predicted by the volume of searches for pharyngitis, laryngitis and hoarseness.

CONCLUSIONS

The epidemiological burden of throat symptoms has considerably changed after Omicron emergence, with a lower likelihood of developing chemosensory dysfunctions and enhanced risk of throat involvement.

Association between viral load and positivization time of a SARS-CoV-2 rapid antigen test in routine nasopharyngeal specimens

BACKGROUND

Rapid SARS-CoV-2 antigen tests are potentially useful tools for screening carriers with high viral load. This study was aimed to assess the potential association between viral load and positivization time of a manual SARS-CoV-2 commercial antigen test in routine nasopharyngeal specimens.

METHODS

In a sample of subjects undergoing routine diagnostic testing, SARS-CoV-2 positivity of nasopharyngeal samples was assayed with both molecular (Altona Diagnostics RealStar SARS-CoV-2 RT-PCR Kit) and antigenic (Roche SARS-CoV-2 Rapid Antigen Test) tests. Positivization time of rapid antigen test was correlated and compared with viral load expressed as mean of SARS-CoV2 E/S genes cycle threshold (Ct) values.

RESULTS

The study sample consisted of 106 patients (median age 48 years, 55 women) with positive results of rapid SARS-CoV-2 antigen testing. A highly significant Spearman's correlation was found between mean SARSCoV-2 E/S genes Ct values and positivization time of manual antigen test (r= 0.70; p<0.001). The positivization time of rapid SARS-CoV-2 antigen test displayed an area under the curve of 0.82 (95%CI, 0.74-0.89) for predicting nasopharyngeal samples with high viral load (i.e., mean Ct <20). A positivization time cut-off of 32 SEC had 94.9% sensitivity and 58.2% specificity for detecting specimens with high viral load. The overall agreement between mean Ct value <20 and positivization time <32 SEC was 70.8%.

CONCLUSIONS

Positivization time of rapid SARS-CoV-2 antigen tests may provide easy and rapid information on viral load, thus making this type of manual assay potentially suitable for quick and reliable detection and isolation of supercarriers.

Coronavirus disease 2019, hypertension, and renin-angiotensin-aldosterone system inhibitors

PURPOSE OF REVIEW

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mostly uses the angiotensin-converting enzyme 2 (ACE-2) as cellular receptor for entering the host cells. Some, but not all, animal studies have shown that renin-angiotensin-aldosterone system (RAAS) inhibitors can increase ACE-2 expression. On that premise, it was hypothesized that these agents could make it more likely to develop coronavirus disease 2019 (COVID-19). On the other hand, there was also evidence that being on these agents could lessen the severity of the lung injury in patients with severe SARS-CoV-2 infection. Herein, we review the available evidence on the role of RAAS inhibitors on SARS-CoV-2 and COVID-19 development.

RECENT FINDINGS

Recent randomized controlled trials demonstrate that RAAS blockade or withdrawal does not influence the severity of COVID-19 in patients who are already on these medications. Currently, there is no evidence to support stopping RAAS inhibitors in patients hospitalized for COVID-19. Several questions still need to be addressed. Ongoing studies are currently evaluating the de novo use of RAAS inhibitors in patients with COVID-19. Another area that needs to be investigated is whether or not using these medications increase the risk of infection.

SUMMARY

The wealth of evidence indicates that ACE inhibitors and angiotensin-receptor blocker administration has no harmful effects on hospitalizations and severity of COVID-19 in patients already on these medications and might even reduce mortality among hypertensive patients diagnosed with COVID-19. More evidence and data need to be collected, and at this time, these agents should not be discontinued.

Regional Association between Mean Air Temperature and Case Numbers of Multiple SARS-CoV-2 Lineages throughout the Pandemic

The association between mean air temperature and new SARS-CoV-2 case numbers throughout the ongoing coronavirus disease 2019 (COVID-19) pandemic was investigated to identify whether diverse SARS-CoV-2 lineages may exhibit diverse environmental behaviors. The number of new COVID-19 daily cases in the province of Verona was obtained from the Veneto Regional Healthcare Service, whilst the mean daily air temperature during the same period was retrieved from the Regional Agency for Ambient Prevention and Protection of Veneto. A significant inverse correlation was found between new COVID-19 daily cases and mean air temperature in Verona up to Omicron BA.1/BA.2 predominance (correlation coefficients between −0.79 and −0.41). The correlation then became positive when the Omicron BA.4/BA.5 lineages were prevalent (r = 0.32). When the median value (and interquartile range; IQR) of new COVID-19 daily cases recorded during the warmer period of the year in Verona (June–July) was compared across the three years of the pandemic, a gradual increase could be seen over time, from 1 (IQR, 0–2) in 2020, to 22 (IQR, 11–113) in 2021, up to 890 (IQR, 343–1345) in 2022. These results suggest that measures for preventing SARS-CoV-2 infection should not be completely abandoned during the warmer periods of the year.

Systematic Review of Diagnostic Accuracy of DiaSorin Liaison SARS-CoV-2 Antigen Immunoassay

Background

Quantification of SARS-CoV-2 antigens by means of rapid, high-throughput and fully-automated techniques has been proposed as a feasible alternative to overcome the current shortage of resources for routine molecular diagnostics. To this end, we provide here a systematic review of diagnostic accuracy of DiaSorin Liaison SARS-CoV-2 antigen immunoassay.

Methods

An electronic search was conduced in Medline and Scopus, with no language or date restrictions (up to January 20, 2022), for identifying all published studies articles in which the diagnostic performance of the DiaSorin Liaison SARS-CoV-2 antigen immunoassay was compared with molecular diagnostic techniques.

Results

The electronic search identified a final number of 11 studies, totalling 4449 oro- and naso-pharyngeal specimens. The pooled diagnostic sensitivity, specificity and area under the curve (AUC) of the Liaison SARS-CoV-2 antigen immunoassay in all samples were 0.51 (95%CI, 0.49-0.54), 1.00 (95%CI, 1.00-1.00) and 0.994 (95%CI, 0.990-0.998), respectively, whilst the overall concordance with molecular diagnostics was 82.1%. The pooled diagnostic sensitivity, specificity and AUC of the Liaison SARS-CoV-2 antigen immunoassay in specimens with high viral load (i.e., cycle threshold values <25-30) were 0.79 (95%CI, 0.75-0.82), 1.00 (95%CI, 0.99-1.00) and 0.911 (95%CI, 0.879-0.943), respectively, whilst the overall concordance with molecular diagnostics in such samples increased to 94.2%.

Conclusion

The results of this systematic literature review suggest that there is sufficient accuracy of the DiaSorin Liaison SARS-CoV-2 antigen immunoassay in samples with high viral loads that would enable its reliable usage for identifying superspreaders, who are responsible for the vast majority of transmission events.