Confirmation of radiant catalytic ionization efficacy for airborne SARS-CoV-2 elimination indoors using "COVID19 traps".

Radiant catalytic ionization (RCI) is a novel technology that uses the appropriate wavelength (240-260 nm) and the phenomenon of photo-oxidation leading to permanent removal of viruses, bacteria, and fungi. Here, two analyses were performed. The first of them was a complete analysis of environmental biosecurity in a hospital environment. The second one was a longitudinal study with 40 patients with confirmed COVID19 and high viral load to assess the efficacy of RCI technology eliminating airborne SARS-CoV-2 indoors. A significant decrease in the number of bacteria and fungi colony-forming units (CFUs) was found in rooms with RCI when compared with rooms without it (p=0.03 for both of them). In the second part of the study, 16 samples out of 40 (40%) were positives when RCI technology was absent; whereas, these samples were negative when the equipment was on. Incidence rates (IR) with their Poisson 95% Confidence Intervals (CI) were calculated as the number of positive tests with the purifier or without it, showing an IR difference of 48.5% [CI(15.9-81), p=0.004]. Furthermore, the IR ratio was calculated obtaining a value of 3.3, confirming that RCI diminished more than 3-fold the presence of the SARS-CoV-2 in the air of the patients' rooms, thus laying the first stone in the fight for prevention of SARS-CoV-2 dissemination indoors.

ShellCoat, a Calcinated Calcium Solution, Effectively Inactivates SARS-CoV-2.

SARS-CoV-2, an acute respiratory syndrome-causing virus, suddenly emerged at the end of 2019 in China, and rapidly spread all over the world. In this study, we examined whether a calcinated calcium solution (ShellCoat) , which has been approved as a food additive in Japan can inactivate SARS-CoV-2. Furthermore, antiviral activity of ShellCoat against SARS-CoV-2 was also evaluated in the presence of organic matter, namely, fetal bovine serum (FBS) . When concentrated SARS-CoV-2 were treated with ShellCoat for 10 sec in presence or absence of FBS as organic matters, the viral titer was decreased more than 4 logs 50% tissue culture infective dose per mL (TCID50/mL) but use of ShellCoat for 20 sec or more under similar experimental conditions the viral titer was below the detection limit (≦2.1 logs TCID50/mL) . These results clearly indicate that the ShellCoat is a powerful antiviral agent against SARS-CoV-2 even in the presence of organic matters.

Prepandemic Predictors of Medication Adherence and HIV Viral Load During the First Year of COVID-19.

ABSTRACT: Studies have reported significant immediate impacts of the COVID-19 pandemic on the social relationships and health care of people living with HIV. This study followed a closed cohort of young people living with HIV over the first year of the COVID-19 pandemic. Participants were men and women (N = 140) age 36 years and younger who were living with HIV and had demonstrated suboptimal adherence to antiretroviral therapy, unsuppressed HIV viral load, or active substance use in a run-in study. The results confirmed that participants continued to experience significant disruptions to their social relationships and health care over the course of the first year of the COVID-19 pandemic. There was evidence for sustained impacts on transportation, housing stability, and food security during the first year of COVID-19. Multivariable models showed that greater pre-COVID-19 social support predicted greater antiretroviral therapy adherence and greater HIV suppression (lower viral load) over the first year of the COVID-19 pandemic. Efforts to plan and prepare people living with HIV for future social crises, including future pandemics, should emphasize building and sustaining social support.

Is chlorhexidine mouthwash effective in lowering COVID-19 viral load? A systematic review.

OBJECTIVE: This review aims to determine whether there is considerable evidence that mouthwashes containing chlorhexidine (CHX) lower the COVID-19 virus load in saliva. MATERIALS AND METHODS: A comprehensive literature search was carried out in PubMed/Medline, EMBASE, LILACS, Scopus, Web of Science and Cochrane Library, Google Scholar, Open Gray, and ProQuest electronic databases using the keywords: "coronavirus infections" or "coronavirus" or "covid 2019" or "sars 2" or "sars-cov-2" or "sars-cov-19" or "severe acute respiratory syndrome coronavirus 2" or "coronavirus infection" or "severe acute respiratory pneumonia outbreak" and "CHX" or "CHX Hydrochloride" or "CHX Digluconate." A manual search of the articles was also conducted utilizing the reference lists of articles. The in vitro experimental and clinical studies that tested CHX mouthwash were included. Study selection was not restricted or limited to a specific gender, age, ethnicity of individuals, or time of publication. A mix of keywords and proper truncations were used to search for databases. RESULTS: Twelve studies (7 clinical and 5 in vitro) published between 2020 and 2021 were included in this systemic review. Five randomized controlled trials and one clinical case series demonstrated the effectiveness of CHX in reducing the oral viral load; one was inconclusive. Of the five in vitro studies, three showed that CHX is effective against SARS-CoV-2, and two studies denied the effectiveness of CHX. All in vitro studies tested CHX activity concentrations of 0.2, 0.12, and 0.1%. One study reported more than a 99.9% reduction in SARS-CoV-2 viral load in a minimal contact time of 30 seconds. CHX exhibited potent antiviral activity at higher concentrations without cytotoxicity. CONCLUSIONS: Despite differences in the published research, CHX at different concentrations may be effective in lowering the SARS-COV-2 viral load in saliva.

Association of SARS-CoV-2 viral load with biochemical profile of COVID-19 patients: A nigerian experience.

Background: Kidney involvement in coronavirus disease 2019 (COVID-19) pathology has been supported by high frequency of angiotensin-converting enzyme 2 (ACE2) expression on renal cells and reports of acute kidney injury. However, the association between host viral load and kidney function is not clear. Aim: In this study, plasma levels of renal markers (urea nitrogen, creatinine, and estimated glomerular filtration rate (eGFR)) and electrolytes (sodium, potassium, chlorine, and bicarbonate) were assessed in relation to SARS-CoV-2 viral load of COVID-19 patients. Patients and Methods: This cross-sectional study involved 144 consenting COVID-19 patients admitted to the Ogun state COVID-19 isolation center between May and December 2020. All participants presented with mild respiratory symptoms and did not require ICU admission or ventilation support. Data included reverse transcriptase polymerase chain reaction (RT-PCR) cycle threshold (CT) value, blood urea nitrogen (BUN), creatinine, sodium, potassium, chlorine, bicarbonate measurements, and glomerular filtration rate. Reference intervals were used as comparators, and multiple linear regression model was fitted. Statistical significance was set at P < 0.05. Results: BUN level and creatinine were elevated in 4 (2.8%) and 42 (29.2%) patients, respectively, with lowered eGFR observed in 37 (25.7%) patients. Hyponatremia and hypokalemia were observed in 35 (24.3%) and 21 (14.6%) patients, respectively, while hypochloremia was observed in 21 (14.6%) patients. Lowered bicarbonate was observed in 29 (20.1%) patients. Linear regression showed statistically significant association (R2 = 0.340, P = 0.032) between RT-PCR CT value and eGFR (ß = 0.006, P = 0.017) as well as HCO3 (ß = -0.262, P = 0.036). Conclusion: COVID-19 patients with mild respiratory symptoms exhibited renal abnormalities, electrolytes, and acid-base imbalances which were partly associated with SARS-CoV-2 viral load.

#Stayathome If You Have a Cold: High SARS-CoV-2 Salivary Viral Loads in Pediatric Patients with Nasopharyngeal Symptoms.

The choice of the best SARS-CoV-2 detection approach is crucial to predict which children with SARS-CoV-2 are at high risk of spreading the virus in order to manage public health measures and policies. In this prospective observational study of 35 children admitted to the Pediatric Emergency Departments of two tertiary hospitals in Northern Italy who tested positive for SARS-CoV-2 by standard RT-PCR in nasopharyngeal swab (NPS), we evaluated their presenting symptoms according to their salivary viral load (SVL) determined by droplet digital PCR (ddPCR). Despite an overall low concordance between SARS-CoV-2 detected by salivary ddPCR and NPS RT-PCR (54.3%), when only patients with nasopharyngeal symptoms were analyzed, the sensitivity of ddPCR in saliva specimens increased to 71.4%, and over half of these patients had high SVL (>105 copies/mL), which was significantly more frequent than in children without nasopharyngeal symptoms (57.1% vs. 14.3%, OR = 8, CI 95% 1.28−50.03, p = 0.03). All asymptomatic children had low SVL values. Our findings support the hypothesis that children with nasopharyngeal symptoms are at higher risk of spreading SARS-CoV-2 due to their high SVL and, conversely, asymptomatic children are unlikely to spread the virus due to their low SVL, regardless of their NPS positivity.

Viral load and its relationship with the inflammatory response and clinical outcomes in hospitalization of patients with COVID-19.

Background: The values of viral load in COVID-19 disease have gained relevance, seeking to understand its prognostic value and its behavior in the course of the disease, although there have been no conclusive results. In this study we sought to analyze serum viral load as a predictor of clinical outcome of the disease, as well as its association with inflammatory markers. Methods: An observational and retrospective study in a private hospital in North Mexico, patients with SARS-COV-2 infection confirmed by reverse transcriptase polymerase chain reaction (RT-PCR) were followed through clinical outcome, viral load measurement, quantification of inflammatory markers and lymphocyte subpopulations. For the analysis, multiple regression models were performed. Results: We studied 105 patients [47 (SD 1.46) years old, 68.6% men]. After analysis with multiple regression models, there was an association between viral load at admission and vaccination schedule (ß-value=-0.279, p= 0.007), age (ß-value= 0.010, p = 0.050), mechanical ventilation (ß-value= 0.872, p = 0.007), lactate dehydrogenase (ß-value= 1.712, p= 0.004), D-dimer values at admission (ß-value= 0.847, p= 0.013) and subpopulation of B lymphocytes at admission (ß-value= -0.527, p= 0.042). There was no association with days of hospitalization, use of nasal prongs or high flux mask. Peak viral load (10 days after symptoms onset) was associated with peak IL-6 (ß-value= 0.470, p= 0.011). Peak viral load matched with peak procalcitonin and minimal lymphocyte values. C-reactive protein peak was before the peak of viral load. The minimum value viral load was documented on day 12 after symptom onset; it matched with the minimum values of IL-6 and ferritin, and the peak of D-dimer. Conclusions: SARS-COV-2 admission viral load is associated with vaccination status, mechanical ventilation, and different inflammatory markers.

Accurate Detection of SARS-CoV-2 by Next-Generation Sequencing in Low Viral Load Specimens.

As new SARS-CoV-2 variants emerge, there is an urgent need to increase the efficiency and availability of viral genome sequencing, notably to detect the lineage in samples with a low viral load. SARS-CoV-2 genome next-generation sequencing (NGS) was performed retrospectively in a single center on 175 positive samples from individuals. An automated workflow used the Ion AmpliSeq SARS-CoV-2 Insight Research Assay on the Genexus Sequencer. All samples were collected in the metropolitan area of the city of Nice (France) over a period of 32 weeks (from 19 July 2021 to 11 February 2022). In total, 76% of cases were identified with a low viral load (Ct ≥ 32, and ≤200 copies/µL). The NGS analysis was successful in 91% of cases, among which 57% of cases harbored the Delta variant, and 34% the Omicron BA.1.1 variant. Only 9% of cases had unreadable sequences. There was no significant difference in the viral load in patients infected with the Omicron variant compared to the Delta variant (Ct values, p = 0.0507; copy number, p = 0.252). We show that the NGS analysis of the SARS-CoV-2 genome provides reliable detection of the Delta and Omicron SARS-CoV-2 variants in low viral load samples.

The clinical and virological features of two children's coinfections with human adenovirus type 7 and human coronavirus-229E virus.

Objective: Human adenovirus (HAdV) coinfection with other respiratory viruses is common, but adenovirus infection combined with human coronavirus-229E (HCoV-229E) is very rare. Study design and setting: Clinical manifestations, laboratory examinations, and disease severity were compared between three groups: one coinfected with HAdV-Ad7 and HCoV-229E, one infected only with adenovirus (mono-adenovirus), and one infected only with HCoV-229E (mono-HCoV-229E). Results: From July to August 2019, there were 24 hospitalized children: two were coinfected with HAdV-Ad7 and HCoV-229E, and 21 were infected with a single adenovirus infection. Finally, one 14-year-old boy presented with a high fever, but tested negative for HAdV-Ad7 and HCoV-229E. Additionally, three adult asymptotic cases with HCoV-229E were screened. No significant difference in age was found in the coinfection and mono-adenovirus groups (11 vs. 8 years, p = 0.332). Both groups had the same incubation period (2.5 vs. 3 days, p = 0.8302), fever duration (2.5 vs. 2.9 days, p = 0.5062), and length of hospital stay (7 vs. 6.76 days, p = 0.640). No obvious differences were found in viral loads between the coinfection and mono-adenovirus groups (25.4 vs. 23.7, p = 0.570), or in the coinfection and mono-HCoV-229E groups (32.9 vs. 30.06, p = 0.067). All cases recovered and were discharged from the hospital. Conclusion: HAdV-Ad7 and HCoV-229E coinfection in healthy children may not increase the clinical severity or prolong the clinical course. The specific interaction mechanism between the viruses requires further study.

Intranasal inoculation of IFN-λ resolves SARS-CoV-2 lung infection via the rapid reduction of viral burden and improvement of tissue damage.

Introduction: The innate immune responses of upper airway could further our understanding toward antiviral strategies against SARS-CoV-2. We characterize the potential of interferon (IFN)-λ as an innate immune inducer for the rapid clearance of SARS-CoV-2 in the lung and the therapeutic efficacy of intranasal inoculation of IFN-λ to resolve acute lung infection. Methods: Syrian golden hamsters were infected with SARS-CoV-2 and the dynamics of SARS-CoV-2 infection depending on IFN-λ inoculation were tested. Results: SARS-CoV-2-infected Syrian golden hamsters exhibited a significant decrease in body weight and high viral mRNA level at 3 days post-infection (dpi). Although viral replication was reduced completely from 7 dpi, the pathologic findings remained prominent until 14 dpi in the lung of hamsters. The transcription of IFN-λ was significantly induced in response to SARS-CoV-2 infection with the increase of IFN-stimulated genes. Intranasal inoculation of IFN-λ restricted SARS-CoV-2 replication in the lungs of infected completely from 3 dpi with markedly reduction of inflammatory cytokines. The transcriptional phenotypes were altered to the direction of damage repair and tissue remodeling in the lungs of SARS-CoV-2-infected hamsters following intranasal inoculation of IFN-λ, which improved SARS-CoV-2-caused lung damage. Conclusion: Collectively, our findings suggest that IFN-λ might be a potent innate immune inducer in the lung and intranasal inoculation of IFN-λ resolves SARS-CoV-2 infection with rapid viral clearance and improvement of lung damage.

Association of SARS-CoV-2 viral load distributions with individual demographics and suspected variant type: results from the Liverpool community testing pilot, England, 6 November 2020 to 8 September 2021.

BackgroundThe PCR quantification cycle (Cq) is a proxy measure of the viral load of a SARS-CoV-2-infected individual.AimTo investigate if Cq values vary according to different population characteristics, in particular demographic ones, and within the COVID-19 pandemic context, notably the SARS-CoV-2 type/variant individuals get infected with.MethodsWe considered all positive PCR results from Cheshire and Merseyside, England, between 6 November 2020 and 8 September 2021. Cq distributions were inspected with Kernel density estimates. Multivariable quantile regression models assessed associations between people's features and Cq.ResultsWe report Cq values for 188,821 SARS-CoV-2 positive individuals. Median Cqs increased with decreasing age for suspected wild-type virus and Alpha variant infections, but less so, if not, for Delta. For example, compared to 30-39-year-olds (median age group), 5-11-year-olds exhibited 1.8 (95% CI: 1.5 to 2.1), 2.2 (95% CI: 1.8 to 2.6) and 0.8 (95% CI: 0.6 to 0.9) higher median Cqs for suspected wild-type, Alpha and Delta positives, respectively, in multivariable analysis. 12-18-year-olds also had higher Cqs for wild-type and Alpha positives, however, not for Delta. Overall, in univariable analysis, suspected Delta positives reported 2.8 lower median Cqs than wild-type positives (95% CI: 2.7 to 2.8; p < 0.001). Suspected Alpha positives had 1.5 (95% CI: 1.4 to 1.5; p < 0.001) lower median Cqs than wild type.ConclusionsWild-type- or Alpha-infected school-aged children (5-11-year-olds) might transmit less than adults (> 18 years old), but have greater mixing exposures. Smaller differences in viral loads with age occurred in suspected Delta infections. Suspected-Alpha- or Delta-infections involved higher viral loads than wild type, suggesting increased transmission risk. COVID-19 control strategies should consider age and dominant variant.

Torque teno virus (TTV): A gentle spy virus of immune status, predictive marker of seroconversion to COVID-19 vaccine in kidney and lung transplant recipients.

To date, no comprehensive marker to monitor the immune status of patients is available. Given that Torque teno virus (TTV), a known human virome component, has previously been identified as a marker of immunocompetence, it was retrospectively investigated whether TTV viral load may also represent a marker of ability to develop antibody in response to COVID-19-BNT162B2 vaccine in solid organ transplant recipients (SOT). Specifically, 273 samples from 146 kidney and 26 lung transplant recipients after successive doses of vaccine were analyzed. An inverse correlation was observed within the TTV copy number and anti-Spike IgG antibody titer with a progressive decrease in viremia the further away from the transplant date. Analyzing the data obtained after the second dose, a significant difference in TTV copy number between responsive and nonresponsive patients was observed, considering a 5 log10 TTV copies/mL threshold to discriminate between the two groups. Moreover, for 86 patients followed in their response to the second and third vaccination doses a 6 log10 TTV copies/mL threshold was used to predict responsivity to the booster dose. Although further investigation is necessary, possibly extending the analysis to other patient categories, this study suggests that TTV can be used as a good marker of vaccine response in transplant patients.

Is chlorhexidine mouthwash effective in lowering COVID-19 viral load? A systematic review.

OBJECTIVE: This review aims to determine whether there is considerable evidence that mouthwashes containing chlorhexidine (CHX) lower the COVID-19 virus load in saliva. MATERIALS AND METHODS: A comprehensive literature search was carried out in PubMed/Medline, EMBASE, LILACS, Scopus, Web of Science and Cochrane Library, Google Scholar, Open Gray, and ProQuest electronic databases using the keywords: "coronavirus infections" or "coronavirus" or "covid 2019" or "sars 2" or "sars-cov-2" or "sars-cov-19" or "severe acute respiratory syndrome coronavirus 2" or "coronavirus infection" or "severe acute respiratory pneumonia outbreak" and "CHX" or "CHX Hydrochloride" or "CHX Digluconate." A manual search of the articles was also conducted utilizing the reference lists of articles. The in vitro experimental and clinical studies that tested CHX mouthwash were included. Study selection was not restricted or limited to a specific gender, age, ethnicity of individuals, or time of publication. A mix of keywords and proper truncations were used to search for databases. RESULTS: Twelve studies (7 clinical and 5 in vitro) published between 2020 and 2021 were included in this systemic review. Five randomized controlled trials and one clinical case series demonstrated the effectiveness of CHX in reducing the oral viral load; one was inconclusive. Of the five in vitro studies, three showed that CHX is effective against SARS-CoV-2, and two studies denied the effectiveness of CHX. All in vitro studies tested CHX activity concentrations of 0.2, 0.12, and 0.1%. One study reported more than a 99.9% reduction in SARS-CoV-2 viral load in a minimal contact time of 30 seconds. CHX exhibited potent antiviral activity at higher concentrations without cytotoxicity. CONCLUSIONS: Despite differences in the published research, CHX at different concentrations may be effective in lowering the SARS-COV-2 viral load in saliva.

Upper respiratory tract viral load quantification in COVID-19 patients at hospital admission and its association with disease severity.

INTRODUCTION: There are aspects of COVID-19 pathogenesis that are still unknown. OBJECTIVE: To determine the relationship between severity, mortality and viral replication in patients with COVID-19. METHODS: Clinical characteristics, severity and mortality of 203 patients hospitalized for COVID-19 were analyzed and correlated with viral load (VL) and threshold cycle (TC) at admission; nasopharyngeal swab was obtained. RESULTS: Mean VLs in surviving patients with mild to moderate, moderate to severe and severe disease were the following: 6.8 x 106, 7.6 x 107 and 1.0 x 109, respectively; and in patients with critical disease who died, VL was 1.70 x 109. TCs were 26.06, 24.07, 22.66 and 21.78 for the same groups. In those who died, a higher mean VL was observed at admission in comparison with those who survived (1.7 x 109 vs. 9.84 x 106; p < 0.001). A significant correlation was observed between VL, severity and death (r = 0.254, p < 0.045 and r = 0.21, p < 0.015). High VL was associated with increased in-hospital mortality in comparison with low VL (OR = 2.926, p < 0.017). CONCLUSION: SARS-CoV-2 VL determined at hospital admission might classify risk simultaneously with other factors described in COVID-19.

INTRODUCCIÓN: Aún se desconocen aspectos de la patogenia de COVID-19. OBJETIVO: Determinar la relación entre gravedad, mortalidad y replicación viral en pacientes con COVID-19. MÉTODOS: Se analizaron características clínicas, gravedad de la enfermedad y mortalidad de 203 pacientes hospitalizados por COVID-19 y se correlacionaron con carga viral (CV) y ciclo umbral (Ct) al ingreso; se tomó hisopado nasofaríngeo. RESULTADOS: Las CV medias en los pacientes sobrevivientes fueron las siguientes ante enfermedad leve a moderada, moderada a grave y grave: 6.8 × 106, 7.6 × 107 y 1.0 × 109; y en los pacientes con enfermedad crítica que fallecieron, la CV fue de 1.70 × 109. Los Ct fueron 26.06, 24.07, 22.66 y 21.78 para esos mismos grupos. En quienes fallecieron se observó mayor CV media al ingreso en comparación con quienes sobrevivieron (1.7 × 109 versus 9.84 × 106), p < 0.001. Se evidenció correlación significativa entre CV, gravedad y muerte (r = 0.254, p < 0.045 y r = 0.21, p < 0.015). La CV alta se asoció a mayor mortalidad intrahospitalaria en comparación con la CV baja (RM = 2.926, p < 0.017). CONCLUSIÓN: La CV de SARS-CoV-2 determinada al ingreso hospitalario podría calificar el riesgo simultáneamente con otros factores descritos en COVID-19.

Nasopharyngeal viral load at admission is not an independent predictor of thromboembolic complications in unvaccinated COVID-19 hospitalized patients.

COVID-19 patients may develop thrombotic complications, and data regarding an association between nasopharyngeal viral load and thrombosis is scarce. The aim of our study was to evaluate whether SARS-CoV-2 nasopharyngeal viral load upon admission is a useful prognostic marker for the development of thromboembolic events in patients hospitalized for SARS-CoV-2 infection. We performed a retrospective study of all hospitalized patients with a positive PCR test for SARS-CoV2 who had deep vein thrombosis (DVT), pulmonary embolization (PE), or arterial thrombosis diagnosed during their clinical course in a single academic center. The study population was divided according to the cycle threshold (Ct) value upon admission in patients with high viral load (Ct < 25), intermediate/medium viral load (Ct 25-30), and low viral load (Ct > 30). A regression model for propensity was performed matching in a 1:3 ratio those patients who had a thrombotic complication to those who did not. Among 2,000 hospitalized COVID-19 patients, 41 (2.0%) developed thrombotic complications. Of these, 21 (51.2%) were diagnosed with PE, eight (19.5%) were diagnosed with DVT, and 12 (29.2%) were diagnosed with arterial thrombosis. Thrombotic complications occurred as frequently among the nasopharyngeal viral load or severity stratification groups with no statistically significant differences. Univariate logistic regression revealed increased odds for thrombosis only in mechanically ventilated patients OR 3.10 [1.37, 7.03] (p = 0.007). Admission SARS-CoV-2 nasopharyngeal viral loads, as determined by Ct values, were not independently associated with thromboembolic complications among hospitalized patients with COVID-19.

Mouth rinses efficacy on salivary SARS-CoV-2 viral load: A randomized clinical trial.

Considering the global trend to confine the COVID-19 pandemic by applying various preventive health measures, preprocedural mouth rinsing has been proposed to mitigate the transmission risk of SARS-CoV-2 in dental clinics. The study aimed to investigate the effect of different mouth rinses on salivary viral load in COVID-19 patients. This study was a single-center, randomized, double-blind, six-parallel-group, placebo-controlled clinical trial that investigated the effect of four mouth rinses (1% povidone-iodine, 1.5% hydrogen peroxide, 0.075% cetylpyridinium chloride, and 80 ppm hypochlorous acid) on salivary SARS-CoV-2 viral load relative to the distilled water and no-rinse control groups. The viral load was measured by quantitative reverse transcription PCR (RT-qPCR) at baseline and 5, 30, and 60 min post rinsing. The viral load pattern within each mouth rinse group showed a reduction overtime; however, this reduction was only statistically significant in the hydrogen peroxide group. Further, a significant reduction in the viral load was observed between povidone-iodine, hydrogen peroxide, and cetylpyridinium chloride compared to the no-rinse group at 60 min, indicating their late antiviral potential. Interestingly, a similar statistically significant reduction was also observed in the distilled water control group compared to the no-rinse group at 60 min, proposing mechanical washing of the viral particles through the rinsing procedure. Therefore, results suggest using preprocedural mouth rinses, particularly hydrogen peroxide, as a risk-mitigation step before dental procedures, along with strict adherence to other infection control measures.

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.

Is SARS-CoV-2 viral load a predictor of mortality in COVID-19 acute respiratory distress syndrome patients?

OBJECTIVE: Viral load varies during infection and is higher during the initial stages of disease. Given the importance of the intensive care unit (ICU) in the late stages of COVID-19 infection, analyzing cycle threshold values to detect viral load upon ICU admission can be a clinically valuable tool for identifying patients with the highest mortality risk. METHODS: This was a retrospectively designed study. Patients older than 18 years who tested positive for SARS-CoV-2 PCR and had a PaO2/FiO2 ratio <200 were included in the study. The patient population was divided into two groups: survivors and non-survivors. RESULTS: Two hundred patients were included in the study. In non-survivors, age, relevant ICU admission scores, and procalcitonin levels were significantly higher whereas PaO2/FiO2 ratios and cycle threshold levels were significantly lower than in survivors. CONCLUSION: Viral load at ICU admission has significant prognostic value. In combination with age, comorbidities, and severity scores, viral load may assist clinicians in identifying individuals who need more intensive monitoring. Increased awareness may improve outcomes by allowing the more effective monitoring and treatment of patients. More prospective studies are needed to determine how a high viral load worsens disease and how to avoid irreversible results.

Single-nucleus transcriptomic profiling of multiple organs in a rhesus macaque model of SARS-CoV-2 infection.

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes diverse clinical manifestations and tissue injuries in multiple organs. However, cellular and molecular understanding of SARS-CoV-2 infection-associated pathology and immune defense features in different organs remains incomplete. Here, we profiled approximately 77 000 single-nucleus transcriptomes of the lung, liver, kidney, and cerebral cortex in rhesus macaques ( Macaca mulatta) infected with SARS-CoV-2 and healthy controls. Integrated analysis of the multi-organ dataset suggested that the liver harbored the strongest global transcriptional alterations. We observed prominent impairment in lung epithelial cells, especially in AT2 and ciliated cells, and evident signs of fibrosis in fibroblasts. These lung injury characteristics are similar to those reported in patients with coronavirus disease 2019 (COVID-19). Furthermore, we found suppressed MHC class I/II molecular activity in the lung, inflammatory response in the liver, and activation of the kynurenine pathway, which induced the development of an immunosuppressive microenvironment. Analysis of the kidney dataset highlighted tropism of tubule cells to SARS-CoV-2, and we found membranous nephropathy (an autoimmune disease) caused by podocyte dysregulation. In addition, we identified the pathological states of astrocytes and oligodendrocytes in the cerebral cortex, providing molecular insights into COVID-19-related neurological implications. Overall, our multi-organ single-nucleus transcriptomic survey of SARS-CoV-2-infected rhesus macaques broadens our understanding of disease features and antiviral immune defects caused by SARS-CoV-2 infection, which may facilitate the development of therapeutic interventions for COVID-19.