Viral Load
Recently Published Documents





Viruses ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2071
Marcello Lanari ◽  
Giovanni Battista Biserni ◽  
Matteo Pavoni ◽  
Eva Caterina Borgatti ◽  
Marta Leone ◽  

The gold standard for diagnosis of SARS-CoV-2 infection has been nucleic acid amplification tests (NAAT). However, rapid antigen detection kits (Ag-RDTs), may offer advantages over NAAT in mass screening, generating results in minutes, both as laboratory-based test or point-of-care (POC) use for clinicians, at a lower cost. We assessed two different POC Ag-RDTs in mass screening versus NAAT for SARS-CoV-2 in a cohort of pediatric patients admitted to the Pediatric Emergency Unit of IRCCS—Polyclinic of Sant’Orsola, Bologna (from November 2020 to April 2021). All patients were screened with nasopharyngeal swabs for the detection of SARS-CoV-2-RNA and for antigen tests. Results were obtained from 1146 patients. The COVID-19 Ag FIA kit showed a baseline sensitivity of 53.8% (CI 35.4–71.4%), baseline specificity 99.7% (CI 98.4–100%) and overall accuracy of 80% (95% CI 0.68–0.91); the AFIAS COVID-19 Ag kit, baseline sensitivity of 86.4% (CI 75.0–93.9%), baseline specificity 98.3% (CI 97.1–99.1%) and overall accuracy of 95.3% (95% CI 0.92–0.99). In both tests, some samples showed very low viral load and negative Ag-RDT. This disagreement may reflect the positive inability of Ag-RDTs of detecting antigen in late phase of infection. Among all cases with positive molecular test and negative antigen test, none showed viral loads > 106 copies/mL. Finally, we found one false Ag-RDTs negative result (low cycle thresholds; 9 × 105 copies/mL). Our results suggest that both Ag-RDTs showed good performances in detection of high viral load samples, making it a feasible and effective tool for mass screening in actively infected children.

2021 ◽  
Grazielle Celeste Maktura ◽  
Thomaz Luscher Dias ◽  
Erika Pereira Zambalde ◽  
Bianca Brenha ◽  
Mariene R. Amorim ◽  

The COVID-19 disease caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has two characteristics that distinguish it from other viral infections. It affects more severely people with pre-existing comorbidities and viral load peaks prior to the onset of the symptoms. Investigating factors that could contribute to these characteristics, we found increased mTOR signaling and suppressed genes related to autophagy, lysosome, and vesicle fusion in Vero E6 cells infected with SARS-CoV-2. Transcriptomic data mining of bronchoalveolar epithelial cells from severe COVID-19 patients revealed that COVID-19 severity is associated with increased expression of genes related to mTOR signaling and decreased expression of genes related to au-tophagy, lysosome function, and vesicle fusion. SARS-CoV-2 infection in Vero E6 cells also re-sulted in virus retention inside the cells and trafficking of virus-bearing vesicles between neighboring cells. Our findings support a scenario where SARS-CoV-2 benefits from compromised autophagic flux and inhibited exocytosis in individuals with chronic hyperactivation of mTOR signaling, which might relate to undetectable proliferation and evasion of the immune system.

2021 ◽  
Christopher J Emig ◽  
Marco A Mena ◽  
Steven J Henry ◽  
Adela Vitug ◽  
Christian John Ventura ◽  

Infections from the SARS-CoV-2 virus have killed over 4.6 million people since it began spreading through human populations in late 2019. In order to develop a therapeutic or prophylactic antibody to help mitigate the effects of the pandemic, a human monoclonal antibody (mAb) that binds to the SARS-CoV-2 spike protein was isolated from a convalescent patient following recovery from COVID-19 disease. This mAb, designated AUG-3387, demonstrates a high affinity for the spike protein of the original viral strains and all variants tested to date. In vitro pseudovirus neutralization and SARS-CoV-2 neutralization activity has been demonstrated in vitro. In addition, a dry powder formulation has been prepared using a Thin Film Freezing (TFF) process that exhibited a fine particle fraction (FPF) of 50.95 ± 7.69% and a mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD) of 3.74 ± 0.73 μm and 2.73 ± 0.20, respectively. The dry powder is suitable for delivery directly to the lungs of infected patients using a dry powder inhaler device. Importantly, AUG-3387, administered as a liquid by intraperitoneal injection or the dry powder formulation delivered intratracheally into Syrian hamsters 24 hours after intranasal SARS-CoV-2 infection, demonstrated a dose-dependent reduction in the lung viral load of the virus. These data suggest that AUG-3387 formulated as a dry powder demonstrates potential to treat COVID-19.

Emily Happy Miller ◽  
Medini K. Annavajhala ◽  
Alexander M. Chong ◽  
Heekuk Park ◽  
Yael R. Nobel ◽  

Alterations to the saliva microbiome based on SARS-CoV-2 viral load indicate potential biologically relevant bacterial-viral relationships which may affect clinical outcomes in COVID-19 disease.

Nolwenn Conan ◽  
Mahmoud Badawi ◽  
Menard L. Chihana ◽  
Stephen Wanjala ◽  
Leonard Kingwara ◽  

2021 ◽  
Vol 18 (1) ◽  
Mary K. Irvine ◽  
McKaylee M. Robertson ◽  
Denis Nash ◽  
Sarah G. Kulkarni ◽  
Sarah L. Braunstein ◽  

Abstract Background Medical care re-engagement is critical to suppressing viral load and preventing HIV transmission, morbidity and mortality, yet few rigorous intervention studies address this outcome. We assessed the effectiveness of a Ryan White Part A-funded HIV Care Coordination Program relative to ‘usual care,’ for short-term care re-engagement and viral suppression among people without recent HIV medical care. Methods The Care Coordination Program was launched in 2009 at 28 hospitals, health centers, and community-based organizations in New York City. Designed for people with HIV (PWH) experiencing or at risk for poor HIV outcomes, the Care Coordination Program provides long-term, comprehensive medical case management utilizing interdisciplinary teams, structured health education and patient navigation. The intervention was implemented as a safety-net services program, without a designated comparison group. To evaluate it retrospectively, we created an observational, matched cohort of clients and controls. Using the HIV surveillance registry, we identified individuals meeting program eligibility criteria from December 1, 2009 to March 31, 2013 and excluded those dying prior to 12 months of follow-up. We then matched clients to controls on baseline status (lacking evidence of viral suppression, consistently suppressed, inconsistently suppressed, or newly diagnosed in the past 12 months), start of follow-up and propensity score. For this analysis, we limited to those out of care at baseline (defined as having no viral load test in the 12 months pre-enrollment) and still residing within jurisdiction (defined as having a viral load or CD4 test reported to local surveillance and dated within the 12-month follow-up period). Using a GEE model with binary error distribution and logit link, we compared odds of care re-engagement (defined as having ≥ 2 laboratory events ≥ 90 days apart) and viral suppression (defined as having HIV RNA ≤ 200 copies/mL on the most recent viral load test) at 12-month follow-up. Results Among 326 individuals out of care at baseline, 87.2% of clients and 48.2% of controls achieved care re-engagement (Odds Ratio: 4.53; 95%CI 2.66, 7.71); 58.3% of clients and 49.3% of controls achieved viral suppression (Odds Ratio: 2.05; 95%CI 1.30, 3.23). Conclusions HIV Care Coordination shows evidence of effectiveness for care and treatment re-engagement.

Mi Ae Chu ◽  
Yoon Young Jang ◽  
Dong Won Lee ◽  
Sung Hoon Kim ◽  
Namhee Ryoo ◽  

2021 ◽  
Yosuke Hirotsu ◽  
Toshiharu Tsutsui ◽  
Yumiko Kakizaki ◽  
Yoshihiro Miyashita ◽  
Fumiaki Iwase ◽  

Abstract Vaccination is expected to suppress COVID-19 infection. However, breakthrough infections have increased following vaccination because of the spread of variants of concern, notably Delta (B.1.617.2 lineage). Virological and serological data pertaining to post-vaccination infections are limited. Here, we conducted genome analysis determined the viral lineages that infected patients following vaccination. Changes in viral load, antibody levels, and viral antigen levels following infection were analyzed. At the time of infection, Delta-infected patients had a 6.2-fold and 12.3-fold higher viral load compared with Alpha and other lineages, respectively. Viral lineages (Delta:Alpha:Other) of infection were 0:12:0 in the fully vaccinated group, 1:11:0 in the partially vaccinated group, 9:16:0 in the shortly after vaccination group, and 254:229:165 in the unvaccinated group. Breakthrough infections occurred regardless of retention of high antibody titers following vaccination. At the time of diagnosis, Delta-infected patients showed high viral load with or without vaccination. However, no fully vaccinated patients developed severe disease, and the rapid increase in anti-spike antibodies occurred approximately 1 week after onset of symptoms. Concomitantly, a decrease in viral antigen levels was observed in fully vaccinated patients, shortening the time to negative result by approximately 2 days compared with unvaccinated patients. Collectively, even if breakthrough infection occurs, the rapid antibody response in fully vaccinated individuals contributes to prevention of severe disease, possibly because of suppression of viral replication.

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258421
Fredrikke Christie Knudtzen ◽  
Thøger Gorm Jensen ◽  
Susan Olaf Lindvig ◽  
Line Dahlerup Rasmussen ◽  
Lone Wulff Madsen ◽  

Introduction We aimed to examine if severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) cycle quantification (Cq) value, as a surrogate for SARS-CoV-2 viral load, could predict hospitalisation and disease severity in adult patients with coronavirus disease 2019 (COVID-19). Methods We performed a prospective cohort study of adult patients with PCR positive SARS-CoV-2 airway samples including all out-patients registered at the Department of Infectious Diseases, Odense University Hospital (OUH) March 9-March 17 2020, and all hospitalised patients at OUH March 10-April 21 2020. To identify associations between Cq-values and a) hospital admission and b) a severe outcome, logistic regression analyses were used to compute odds ratios (OR) and 95% Confidence Intervals (CI), adjusting for confounding factors (aOR). Results We included 87 non-hospitalised and 82 hospitalised patients. The median baseline Cq-value was 25.5 (interquartile range 22.3–29.0). We found a significant association between increasing Cq-value and hospital-admission in univariate analysis (OR 1.11, 95% CI 1.04–1.19). However, this was due to an association between time from symptom onset to testing and Cq-values, and no association was found in the adjusted analysis (aOR 1.08, 95% CI 0.94–1.23). In hospitalised patients, a significant association between lower Cq-values and higher risk of severe disease was found (aOR 0.89, 95% CI 0.81–0.98), independent of timing of testing. Conclusions SARS-CoV-2 PCR Cq-values in outpatients correlated with time after symptom onset, but was not a predictor of hospitalisation. However, in hospitalised patients lower Cq-values were associated with higher risk of severe disease.

2021 ◽  
Vol 12 ◽  
Aaron Ermel ◽  
Thankam Paul Thyvalikakath ◽  
Tatiana Foroud ◽  
Babar Khan ◽  
Mythily Srinivasan

Emerging concerns following the severe acute respiratory syndrome coronavirus-2 (SARS-CoV2) pandemic are the long-term effects of coronavirus disease (COVID)-19. Dysgeusia in COVID-19 is supported by the abundant expression of the entry receptor, angiotensin-converting enzyme-2 (ACE2), in the oral mucosa. The invading virus perturbs the commensal biofilm and regulates the host responses that permit or suppress viral infection. We correlated the microbial recognition receptors and soluble ACE2 (sACE2) with the SARS-CoV2 measures in the saliva of COVID-19 patients. Data indicate that the toll-like receptor-4, peptidoglycan recognition protein, and sACE2 are elevated in COVID-19 saliva and correlate moderately with the viral load.

Sign in / Sign up

Export Citation Format

Share Document