COVID-19: Risk Factors Associated with Infectivity and Severity

Contamination dynamics of personal protective equipment (PPE) by SARS-CoV-2 RNA in a makeshift hospital with COVID-19 positive occupants

Background

Personal protective equipment (PPE) helps protect healthcare workers (HCWs) from infection and prevents cross-contamination. Knowledge of the contamination dynamics of PPE during the management of COVID-19 patients in a makeshift hospital is limited.

Aim

To describe the rate of SARS-CoV-2 contamination in PPE and to assess the change of contamination at different time points.

Methods

HCWs were followed up for up to 4 hours with hourly collection of swab samples from PPE surfaces in a makeshift COVID-19 hospital setting. Swabs were tested using quantitative reverse transcription polymerase chain reaction (RT-qPCR) for SARS-CoV-2 RNA.

Results

SARS-CoV-2 was detected on 50.9% of the 1620 swabbed samples from 9 different sites of full-body PPE worn by HCWs. The proportion of sites contaminated with SARS-CoV-2 RNA varied from 10.6% to 95.6%. Viral RNA was most frequently detected from the sole of the outer foot cover (95.6%) and least frequently on the face shield (10.6%). The median Ct values among positive samples were 34.20 (IQR, 32.61-35.22) and 34.05 (IQR, 32.20-35.39) for ORF1ab and N genes, respectively. The highest rate of contamination with SARS-CoV-2 RNA for the PPE swab samples was found after 3 hours of use. The positive rate of outer surface of HEPA filters from air supply device was 82.1% during the full capacity period of the makeshift hospital.

Conclusion

A higher rate of contamination was identified at 3 hours after the entrance to the COVID-19 patient care area. Virus-containing aerosols were trapped in the HEPA filter of air supply equipment, representing a potential protective factor against infection to HCWs.

Association of HLA-DRB1*11 and HLA-DRB1*12 gene polymorphism with COVID-19 in Burkina Faso

BACKGROUND

The clinical manifestations of coronavirus disease (COVID-19) can vary widely, ranging from asymptomatic to severe, and may be influenced by the host genetic background. The aim of the present study was to determine the frequencies of HLA-DRB1*11 and HLA-DRB1*12 allele polymorphisms and their associations with COVID-19.

METHODS

In this cross-sectional study, 198 subjects were enrolled, including 150 COVID-19 positive cases and 48 subjects who tested negative for COVID-19. Participants were recruited from the emergency, intensive care, and infectious diseases departments of the Bogodogo Centre University Hospital (CHU-B) or the routine laboratory of Centre de Recherche Biomoléculaire Pietro Annigoni (CERBA). Genomic DNA was extracted from nasopharyngeal swabs samples and multiplex PCR-SSP was used to detect the HLA-DRB1*11 and HLA-DRB1*12 alleles. The study was approved by CERS (№ 2021-02-033).

RESULTS

The positive cases were categorized into 38 asymptomatic (CC+), 60 symptomatic (NC+), and 52 severe cases (SC+). Females were more frequent in the overall study population (53.0%, 105/198) as well as in the negative group's CC- (68.75%, 33/48) and SC+ (57.69%, 30/52 negative groups, whereas males were more frequent in the CC+ (63.16%, 24/38) and NC+ (53.33%, 32/60) groups. The highest mean age was observed in the SC + group. A frequency of 19.19% (38/198) and 14.65% (29/198) was found for the HLA-DRB1*11 and HLA-DRB1*12 alleles, respectively. Individuals carrying the HLA-DRB1*11 allele had an approximately sixfold higher risk of asymptomatic SARS-CoV-2 infection (OR = 5.72 [1.683-19.442], p = 0.005) based on the association analysis.

CONCLUSIONS

Altogether, the present study reports high frequency of HLA-DRB1*11 and HLA-DRB1*12 alleles within a population from Ouagadougou, Burkina Faso. The results suggest that individuals carrying the HLA-DRB1*11 allele are more susceptible to COVID-19 infection but may not display symptoms.

Transcriptome-based analysis of human peripheral blood reveals regulators of immune response in different viral infections

Introduction

There are difficulties in creating direct antiviral drugs for all viruses, including new, suddenly arising infections, such as COVID-19. Therefore, pathogenesis-directed therapy is often necessary to treat severe viral infections and comorbidities associated with them. Despite significant differences in the etiopathogenesis of viral diseases, in general, they are associated with significant dysfunction of the immune system. Study of common mechanisms of immune dysfunction caused by different viral infections can help develop novel therapeutic strategies to combat infections and associated comorbidities.

Methods

To identify common mechanisms of immune functions disruption during infection by nine different viruses (cytomegalovirus, Ebstein-Barr virus, human T-cell leukemia virus type 1, Hepatitis B and C viruses, human immunodeficiency virus, Dengue virus, SARS-CoV, and SARS-CoV-2), we analyzed the corresponding transcription profiles from peripheral blood mononuclear cells (PBMC) using the originally developed pipeline that include transcriptome data collection, processing, normalization, analysis and search for master regulators of several viral infections. The ten datasets containing transcription data from patients infected by nine viruses and healthy people were obtained from Gene Expression Omnibus. The analysis of the data was performed by Genome Enhancer pipeline.

Results

We revealed common pathways, cellular processes, and master regulators for studied viral infections. We found that all nine viral infections cause immune activation, exhaustion, cell proliferation disruption, and increased susceptibility to apoptosis. Using network analysis, we identified PBMC receptors, representing proteins at the top of signaling pathways that may be responsible for the observed transcriptional changes and maintain the current functional state of cells.

Discussion

The identified relationships between some of them and virus-induced alteration of immune functions are new and have not been found earlier, e.g., receptors for autocrine motility factor, insulin, prolactin, angiotensin II, and immunoglobulin epsilon. Modulation of the identified receptors can be investigated as one of therapeutic strategies for the treatment of severe viral infections.

Geographic disparities and temporal changes of COVID-19 incidence risks in North Dakota, United States

BACKGROUND

COVID-19 is an important public health concern due to its high morbidity, mortality and socioeconomic impact. Its burden varies by geographic location affecting some communities more than others. Identifying these disparities is important for guiding health planning and service provision. Therefore, this study investigated geographical disparities and temporal changes of the percentage of positive COVID-19 tests and COVID-19 incidence risk in North Dakota.

METHODS

COVID-19 retrospective data on total number of tests and confirmed cases reported in North Dakota from March 2020 to September 2021 were obtained from the North Dakota COVID-19 Dashboard and Department of Health, respectively. Monthly incidence risks of the disease were calculated and reported as number of cases per 100,000 persons. To adjust for geographic autocorrelation and the small number problem, Spatial Empirical Bayesian (SEB) smoothing was performed using queen spatial weights. Identification of high-risk geographic clusters of percentages of positive tests and COVID-19 incidence risks were accomplished using Tango's flexible spatial scan statistic. ArcGIS was used to display and visiualize the geographic distribution of percentages of positive tests, COVID-19 incidence risks, and high-risk clusters.

RESULTS

County-level percentages of positive tests and SEB incidence risks varied by geographic location ranging from 0.11% to 13.67% and 122 to 16,443 cases per 100,000 persons, respectively. Clusters of high percentages of positive tests were consistently detected in the western part of the state. High incidence risks were identified in the central and south-western parts of the state, where significant high-risk spatial clusters were reported. Additionally, two peaks (August 2020-December 2020 and August 2021-September 2021) and two non-peak periods of COVID-19 incidence risk (March 2020-July 2020 and January 2021-July 2021) were observed.

CONCLUSION

Geographic disparities in COVID incidence risks exist in North Dakota with high-risk clusters being identified in the rural central and southwest parts of the state. These findings are useful for guiding intervention strategies by identifying high risk communities so that resources for disease control can be better allocated to communities in need based on empirical evidence. Future studies will investigate predictors of the identified disparities so as to guide planning, disease control and health policy.

Association Between ADHD and COVID-19 Infection and Clinical Outcomes: A Retrospective Cohort Study From Electronic Medical Records

OBJECTIVE

Though psychiatric illnesses have been associated with increased COVID-19 infection risk, limited information exists about the relationship between ADHD and COVID-19.

METHODS

Using the TriNetX COVID-19 Research Network, we examined the impact of ADHD diagnosis and treatment on COVID-19 infection rates and outcomes.

RESULTS

ADHD patients had greater risk of COVID-19 (risk ratio (RR) 1.11, 95% CI [1.09, 1.12]). Increased risk was higher in females than males, and highest among Asian and Black patients. Within 60 days after COVID-19 diagnosis, ADHD patients had lower rates of hospitalization (RR 0.91, 95% CI [0.86, 0.96]) and mechanical ventilation (RR 0.69, 95% CI [0.58, 0.83]), and a nonsignificant reduced death rate (RR 0.65, 95% CI [0.42, 1.02]). Patients who recently received ADHD medication had higher rates of COVID-19 (RR 1.13; 95% CI [1.10, 1.15]).

CONCLUSION

ADHD poses increased risk for COVID-19, but may reduce risk of severe outcomes. ADHD medications modestly impacted COVID-19 risk.

Assessing the suitability of long non-coding RNAs as therapeutic targets and biomarkers in SARS-CoV-2 infection

Long non-coding RNAs (lncRNAs) are RNA transcripts that are over 200 nucleotides and rarely encode proteins or peptides. They regulate gene expression and protein activities and are heavily involved in many cellular processes such as cytokine secretion in respond to viral infection. In severe COVID-19 cases, hyperactivation of the immune system may cause an abnormally sharp increase in pro-inflammatory cytokines, known as cytokine release syndrome (CRS), which leads to severe tissue damage or even organ failure, raising COVID-19 mortality rate. In this review, we assessed the correlation between lncRNAs expression and cytokine release syndrome by comparing lncRNA profiles between COVID-19 patients and health controls, as well as between severe and non-severe cases. We also discussed the role of lncRNAs in CRS contributors and showed that the lncRNA profiles display consistency with patients’ clinic symptoms, thus suggesting the potential of lncRNAs as drug targets or biomarkers in COVID-19 treatment.

A Comprehensive Comparison of Clinical Presentation and Outcomes of Kidney Transplant Recipients with COVID-19 during Wave 1 versus Wave 2 at a Tertiary Care Center, India

Data comparing the clinical spectrum of COVID-19 in kidney transplant recipients (KTRs) during the first and second waves of the pandemic in India is limited. Our single-center retrospective study compared the clinical profile, mortality, and associated risk factors in KTRs with COVID-19 during the 1st wave (1^st February 2020 to 31^st January 2021) and the second wave (1^st March-31^st August 2021). 156 KTRs with PCR confirmed SARS-CoV-2 infection treated at a tertiary care hospital in New Delhi during the 1st and the second waves were analyzed. The demographics and baseline transplant characteristics of the patients diagnosed during both waves were comparable. Patients in the second wave reported less frequent hospitalization, though the intensive care unit (ICU) and ventilator requirements were similar. Strategies to modify immunosuppressants such as discontinuation of antinucleoside drugs with or without change in calcineurin inhibitors and the use of steroids were similar during both waves. Overall patient mortality was 27.5%. The demographics and baseline characteristics of survivors and nonsurvivors were comparable. A higher percentage of nonsurvivors presented with breathing difficulty, low SpO₂, and altered sensorium. Both wave risk factors for mortality included older age, severe disease, ICU/ventilator requirements, acute kidney injury (AKI) needing dialysis, Chest Computerized Tomographic (CT) scan abnormalities, and higher levels of inflammatory markers particularly D-dimer and interleukin-6 levels. Conclusions. KTRs in both COVID-19 waves had similar demographics and baseline characteristics, while fewer patients during the second wave required hospitalization. The D-dimer and IL-6 levels are directly correlated with mortality.

A composite ranking of risk factors for COVID-19 time-to-event data from a Turkish cohort

Having a complete and reliable list of risk factors from routine laboratory blood test for COVID-19 disease severity and mortality is important for patient care and hospital management. It is common to use meta-analysis to combine analysis results from different studies to make it more reproducible. In this paper, we propose to run multiple analyses on the same set of data to produce a more robust list of risk factors. With our time-to-event survival data, the standard survival analysis were extended in three directions. The first is to extend from tests and corresponding p-values to machine learning and their prediction performance. The second is to extend from single-variable to multiple-variable analysis. The third is to expand from analyzing time-to-decease data with death as the event of interest to analyzing time-to-hospital-release data to treat early recovery as a meaningful event as well. Our extension of the type of analyses leads to ten ranking lists. We conclude that 20 out of 30 factors are deemed to be reliably associated to faster-death or faster-recovery. Considering correlation among factors and evidenced by stepwise variable selection in random survival forest, 10 ~ 15 factors seem to be able to achieve the optimal prognosis performance. Our final list of risk factors contain calcium, white blood cell and neutrophils count, urea and creatine, d-dimer, red cell distribution widths, age, ferritin, glucose, lactate dehydrogenase, lymphocyte, basophils, anemia related factors (hemoglobin, hematocrit, mean corpuscular hemoglobin concentration), sodium, potassium, eosinophils, and aspartate aminotransferase.

Higher Intake of Dietary Magnesium Is Inversely Associated With COVID-19 Severity and Symptoms in Hospitalized Patients: A Cross-Sectional Study

Background and Aims

Magnesium is an anti-inflammatory mineral that plays a role in the innate immune system, and the relaxation of bronchial smooth muscle warrants additional attention in COVID-19. This study examined the association between magnesium intake and COVID-19 severity and related symptoms in hospitalized patients.

Methods

A cross-sectional study was done enrolling 250 COVID-19 patients aged 18 to 65 years. A validated 168-item online food frequency questionnaire (FFQ) was used to assess dietary magnesium intake. COVID-19 Treatment Guidelines were used to determine COVID-19 severity, and symptoms were evaluated using a standard questionnaire. Crude and adjusted analyses were performed (Model 1: age, sex, and energy intake; Model 2: Model 1 + physical activity, supplements, corticosteroids, and antiviral drugs; Model 3: Model 2 + body mass index).

Results

The mean age of participants was 44.1 ± 12.1 years, and 46% of them had severe COVID-19. Patients at the highest tertile of dietary magnesium intake had lower serum levels of inflammatory biomarkers, including CRP (11.8 ± 2.2 vs. 29.5 ± 2.1 mg/L, p < 0.001) and ESR (15.8 ± 2.4 vs. 34.7 ± 2.4 mm/hr, p < 0.001), than those at the lowest tertile. After controlling for potential confounders, we observed that a higher dietary magnesium intake was associated with a lower odds of severe COVID-19 (OR: 0.32; 95% CI: 0.15–0.70). Also, we found a significant inverse association between dietary magnesium intake and odds of COVID-19 symptoms.

Conclusion

We found that higher intake of dietary magnesium was inversely associated with COVID-19 severity and symptoms.

Factors Associated for COVID19 Severity Among Patients Treated at Selgalu Treatment Center Assosa in Ethiopia: A Case-Control Study

Background

Most people infected with the SARS-CoV-2 virus experienced mild to moderate respiratory illness and recovered without requiring special treatment. However, some became seriously ill with conditions that require medical attention and intensive care unit (ICU) admission. Severity varies among individuals; this may be due to age differences and the presence of underlying disease conditions.

Objective

To identify factors associated with disease severity among COVID19 patients treated at Selgalu treatment center from November 1, 2020, to April 30, 2021.

Methods

A case–control study was implemented among patients admitted to Selgalu COVID19 treatment center in October 2021. A 210 (70 severe disease and 140 non-severe diseases), cases (disease severity), and controls (non-severe disease). Data entered to Epi data 4.6, exported to SPSS 25. A Chi-square test with a p-value of <0.05 was used as a statistically significant difference between characteristics of disease severity and non-severity of disease. Multivariable binary logistic regression was used to determine variables associated with disease severity based on an adjusted odds ratio with 95% CI and p-value < 0.05.

Results

210 (70 cases and 140 controls) selected charts in this study. Patients age category between 40–59 [AOR: 5.30 (2.27–12.34)], aged 60 or older [AOR: 3.85 (1.39–10.64)], patients with fever [AOR: 3.98 (1.59–9.96)], fatigue [AOR: 3.14 (1.50–6.54)], and hypertensive patients [AOR: 3.68 (1.53–8.82)] were significantly predictors for COVID19 disease severity after adjusting for other variables.

Conclusion

From this study, we conclude that being age 60 or older and 40–59 age groups, having symptoms of fever, fatigue, and underlying comorbid illness hypertension. Were identified a significant predictor of severe COVID-19 disease; despite our limitation of study data highlights the important factors associated with disease severity with covid19 admitted to Selgalu treatment center.

Factores asociados con una evolución desfavorable en pacientes diagnosticados de COVID-19 y seguidos en atención primaria en 2020

Objetivo

Conocer los factores asociados con una evolución desfavorable (ED) de pacientes diagnosticados de COVID-19 con seguimiento total o parcial en atención primaria.

Diseño

Serie de casos.

Emplazamiento

Centro de salud urbano.

Participantes

Pacientes de 18 o más años diagnosticados de COVID-19, con confirmación analítica, en 2020 y seguidos por sus médicos de familia, seleccionados por muestreo sistemático.

Mediciones principales

Variable dependiente: ingreso en hospital o fallecimiento por COVID-19. Variables independientes: edad, sexo, antecedentes personales, y datos clínicos y de tratamiento relacionados con la enfermedad. Análisis estadístico, con SPSS 25.0: estadística descriptiva, comparación de proporciones (X²) y medianas (U de Mann-Whitney). Se completó el análisis con regresión logística.

Resultados

Se incluyeron en el estudio 610 pacientes, cuya mediana de edad era de 49 años (rango intercuartiles: 35-61); 51,8% eran mujeres. Presentaron ED 14,9% (IC 95%: 12,0-17,8). Las variables sociodemográficas o relacionadas con antecedentes personales que mostraron una asociación independiente con una ED fueron edad (OR: 1,066; IC 95%:1,038-1,095), sexo (OR para hombre: 3,277; IC 95%: 1,304-8,235) y ser fumador o exfumador (OR: 2,565; IC 95%: 1,135-5,800). En cuanto a variables clínicas propias de la enfermedad, esa asociación se encontró para alteración de la conciencia (OR: 62,829; IC 95%: 9,177-430,149), disnea (OR: 14,339; IC 95%:6,046-34,009), expectoración (OR: 4,764; IC 95%: 1,858-12,213) y astenia (OR: 3,993; IC 95%: 1,705-9,351).

Conclusiones

Presentaron una ED 14,9% de los pacientes diagnosticados de COVID-19. Una mayor edad, el sexo masculino y ser fumador o exfumador aumentaban la probabilidad de ED. Los datos clínicos que mejor predecían la ED fueron alteración de la conciencia, disnea, expectoración y astenia.

Geographic disparities and predictors of COVID-19 hospitalization risks in the St. Louis Area, Missouri (USA)

Background

There is evidence of geographic disparities in COVID-19 hospitalization risks that, if identified, could guide control efforts. Therefore, the objective of this study was to investigate Zip Code Tabulation Area (ZCTA)-level geographic disparities and identify predictors of COVID-19 hospitalization risks in the St. Louis area.

Methods

Hospitalization data for COVID-19 and several chronic diseases were obtained from the Missouri Hospital Association. ZCTA-level data on socioeconomic and demographic factors were obtained from the American Community Survey. Geographic disparities in distribution of COVID-19 age-adjusted hospitalization risks, socioeconomic and demographic factors as well as chronic disease risks were investigated using choropleth maps. Predictors of ZCTA-level COVID-19 hospitalization risks were investigated using global negative binomial and local geographically weighted negative binomial models.

Results

COVID-19 hospitalization risks were significantly higher in ZCTAs with high diabetes hospitalization risks (p < 0.0001), COVID-19 risks (p < 0.0001), black population (p = 0.0416), and populations with some college education (p = 0.0005). The associations between COVID-19 hospitalization risks and the first three predictors varied by geographic location.

Conclusions

There is evidence of geographic disparities in COVID-19 hospitalization risks that are driven by differences in socioeconomic, demographic and health-related factors. The impacts of these factors vary by geographical location implying that a ‘one-size-fits-all’ approach may not be appropriate for management and control. Using both global and local models leads to a better understanding of geographic disparities. These findings are useful for informing health planning to identify geographic areas likely to have high numbers of individuals needing hospitalization as well as guiding vaccination efforts.

COVID-19 Prevalence among Healthcare Workers. A Systematic Review and Meta-Analysis

Understanding the burden of SARS-CoV-2 infections among healthcare workers is a critical component to inform occupational health policy and strategy. We conducted a systematic review and meta-analysis to map and analayse the available global evidence on the prevalence of SARS-CoV-2 infections among healthcare workers. The random-effects adjusted pooled prevalence of COVID-19 among those studies that conducted the test using the antibody (Ab) method was 7% [95% CI: 3 to 17%]. The random-effects adjusted pooled prevalence of COVID-19 among those studies that conducted the test using the PCR method was 11% [95% CI: 7 to 16%]. We found the burden of COVID-19 among healthcare workers to be quite significant and therefore a cause for global health concern. Furthermore, COVID-19 infections among healthcare workers affect service delivery through workers’ sick leave, the isolation of confirmed cases and quarantine of contacts, all of which place significant strain on an already shrunken health workforce.

Predicting respiratory failure in patients infected by SARS-CoV-2 by admission sex-specific biomarkers

BACKGROUND

Several biomarkers have been identified to predict the outcome of COVID-19 severity, but few data are available regarding sex differences in their predictive role. Aim of this study was to identify sex-specific biomarkers of severity and progression of acute respiratory distress syndrome (ARDS) in COVID-19.

METHODS

Plasma levels of sex hormones (testosterone and 17β-estradiol), sex-hormone dependent circulating molecules (ACE2 and Angiotensin1-7) and other known biomarkers for COVID-19 severity were measured in male and female COVID-19 patients at admission to hospital. The association of plasma biomarker levels with ARDS severity at admission and with the occurrence of respiratory deterioration during hospitalization was analysed in aggregated and sex disaggregated form.

RESULTS

Our data show that some biomarkers could be predictive both for males and female patients and others only for one sex. Angiotensin1-7 plasma levels and neutrophil count predicted the outcome of ARDS only in females, whereas testosterone plasma levels and lymphocytes counts only in males.

CONCLUSIONS

Sex is a biological variable affecting the choice of the correct biomarker that might predict worsening of COVID-19 to severe respiratory failure. The definition of sex specific biomarkers can be useful to alert patients to be safely discharged versus those who need respiratory monitoring.

Intravenous immunoglobulin as an important adjunct in the prevention and therapy of coronavirus 2019 disease

The coronavirus disease-19 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) challenged globally with its morbidity and mortality. A small percentage of affected patients (20%) progress into the second stage of the disease clinically presenting with severe or fatal involvement of lung, heart and vascular system, all contributing to multiple-organ failure. The so-called 'cytokines storm' is considered the pathogenic basis of severe disease and it is a target for treatment with corticosteroids, immunotherapies and intravenous immunoglobulin (IVIg). We provide an overview of the role of IVIg in the therapy of adult patients with COVID-19 disease. After discussing the possible underlying mechanisms of IVIg immunomodulation in COVID-19 disease, we review the studies in which IVIg was employed. Considering the latest evidence that show a link between new coronavirus and autoimmunity, we also discuss the use of IVIg in COVID-19 and anti-SARS-CoV-2 vaccination related autoimmune diseases and the post-COVID-19 syndrome. The benefit of high-dose IVIg is evident in almost all studies with a rapid response, a reduction in mortality and improved pulmonary function in critically ill COVID-19 patients. It seems that an early administration of IVIg is crucial for a successful outcome. Studies' limitations are represented by the small number of patients, the lack of control groups in some and the heterogeneity of included patients. IVIg treatment can reduce the stay in ICU and the demand for mechanical ventilation, thus contributing to attenuate the burden of the disease.

Association between the degree of obstructive sleep apnea and the severity of COVID-19: An explorative retrospective cross-sectional study

Obstructive sleep apnea (OSA) on its own, as well as its risk factors, have been found to be associated with the outcome of Coronavirus disease 2019 (COVID-19). However, the association between the degree of OSA and COVID-19 severity is unclear. Therefore, the aim of the study was to evaluate whether or not parameters to clinically evaluate OSA severity and the type of OSA treatment are associated with COVID-19 severity. Patient data from OSA patients diagnosed with COVID-19 were reviewed from outpatients from the Isala Hospital and patients admitted to the Isala Hospital, starting from March until December 2020. Baseline patient data, sleep study parameters, OSA treatment information and hospital admission data were collected. Apnea hypopnea index (AHI), low oxyhemoglobin desaturation (LSAT), oxygen desaturation index (ODI), respiratory disturbance index (RDI), and the type of OSA treatment were regarded as the independent variables. COVID-19 severity-based on hospital or intensive care unit (ICU) admission, the number of days of hospitalization, and number of intubation and mechanical ventilation days-were regarded as the outcome variables. Multinomial regression analysis, binary logistic regression analysis, and zero-inflated negative binomial regression analysis were used to assess the association between the parameters to clinically evaluate OSA severity and COVID-19 severity. A total of 137 patients were included. Only LSAT was found to be significantly associated with the COVID-19 severity (p<0.05) when COVID-19 severity was dichotomized as non-hospitalized or hospitalized and ICU admission or death. Therefore, our findings showed that LSAT seems to be a significant risk factor for COVID-19 severity. However, the degree of OSA-based on AHI, ODI, and RDI-and OSA treatment were not found to be risk factors for COVID-19 severity when looking at hospital or ICU admission, the number of days of hospitalization, and number of intubation and mechanical ventilation days.

Landscape of T-cell repertoires with public COVID-19-associated T-cell receptors in pre-pandemic risk cohorts

Objectives

T cells have an essential role in the antiviral defence. Public T-cell receptor (TCR) clonotypes are expanded in a substantial proportion of COVID-19 patients. We set out to exploit their potential use as read-out for COVID-19 T-cell immune responses.

Methods

We searched for COVID-19-associated T-cell clones with public TCRs, as defined by identical complementarity-determining region 3 (CDR3) beta chain amino acid sequence that can be reproducibly detected in the blood of COVID-19 patients. Of the different clonotype identification algorithms used in this study, deep sequencing of brain tissue of five patients with fatal COVID-19 delivered 68 TCR clonotypes with superior representation across 140 immune repertoires of unrelated COVID-19 patients.

Results

Mining of immune repertoires from subjects not previously exposed to the virus showed that these clonotypes can be found in almost 20% of pre-pandemic immune repertoires of healthy subjects, with lower representation in repertoires from risk groups like individuals above the age of 60 years or patients with cancer.

Conclusion

Together, our data show that at least a proportion of the SARS-CoV-2 T-cell response is mediated by public TCRs that are present in repertoires of unexposed individuals. The lower representation of these clones in repertoires of risk groups or failure to expand such clones may contribute to more unfavorable clinical COVID-19 courses.

COVID-19: Risk Factors Associated with Infectivity and Severity

COVID‐19 is highly transmissible; however, its severity varies from one individual to another. Variability among different isolates of the virus and among its receptor (ACE2) may contribute to this severity, but comorbidity plays a major role on disease prognosis. Many comorbidities have been reported to be associated with severe COVID‐19 patients. We have collected data from retrospective studies which include clinical and epidemiological features of patients and categorize them into severe/mild, ICU/non‐ICU and survivors/dead patients. In this review, we give an update about SARS‐CoV‐2 structure with emphasis on the possible reasons for the severity of the virus in patients. We also collected information and patients’ data to highlight the relation between COVID‐19 patients and comorbidities.