scholarly journals Toothbrushing with a dentifrice containing antimicrobial phthalocyanine derivative for the intraoral reduction of viral load of SARS-CoV-2: a pilot study

2021 ◽  
Author(s):  
Marcelo Lupion Poleti ◽  
Danielle Gregório ◽  
Alisson Gabriel Idelfonso Bistaffa ◽  
Fabiano Vieira Vilhena ◽  
Andréa Name Colado Simão ◽  
...  
Keyword(s):  
Viral Load ◽  
Pilot Study ◽  
Pairwise Comparison ◽  
Rt Pcr ◽  
Significance Level ◽  
Viral Genes ◽  
Friedman's Test ◽  
Unstimulated Saliva ◽  
Phthalocyanine Derivative ◽  
S Genes

Abstract Background: The aim of this study was to evaluate the effects of the toothbrushing with a dentifrice containing antimicrobial phthalocyanine derivative (APD) for the intraoral reduction of viral load of SARS-CoV-2.Material and methods: Twenty COVID-19 positive dentate patients were selected and toothbrushes with a dentifrice containing APD for 2 minutes. Self-collected samples of unstimulated saliva were carried out three times: T0 (baseline, before toothbrushing), T5 (5 minutes after toothbrushing), and T30 (30 minutes after toothbrushing). The analysis of RNA viral was performed by RT-PCR using TaqPath™ COVID-19 multiplex Real-Time RT-PCR test for detection of three viral genes (ORF1ab, N and S genes). Evaluation of the effects was based on difference in cycle threshold (Ct) value. Friedman's test and pairwise comparison with Bonferroni corrections were used, with a significance level of 5%. Results: The Ct values were significantly higher (p=0.020) at T30 in comparison to T0 and T5. The greatest difference in the Ct values was between T30 and T0 (3.83). Conclusion: This pilot study suggests that oral hygiene action associated with an antimicrobial chemical dentifrice may be an important tool for SARS-CoV2 viral load reduction in oral cavity.

scholarly journals A prospective clinical pilot study on the effects of a hydrogen peroxide mouthrinse on the intraoral viral load of SARS-CoV-2

2020 ◽  
Vol 24 (10) ◽  
pp. 3707-3713
Author(s):  
Maximilian J. Gottsauner ◽  
Ioannis Michaelides ◽  
Barbara Schmidt ◽  
Konstantin J. Scholz ◽  
Wolfgang Buchalla ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Clinical Trials ◽  
Viral Load ◽  
Pilot Study ◽  
High Risk ◽  
Infection Prevention ◽  
Healthcare Professionals ◽  
Patient Contact ◽  
Rt Pcr ◽  
Virus Culture

Abstract Objectives SARS-CoV-2 is mainly transmitted by inhalation of droplets and aerosols. This puts healthcare professionals from specialties with close patient contact at high risk of nosocomial infections with SARS-CoV-2. In this context, preprocedural mouthrinses with hydrogen peroxide have been recommended before conducting intraoral procedures. Therefore, the aim of this study was to investigate the effects of a 1% hydrogen peroxide mouthrinse on reducing the intraoral SARS-CoV-2 load. Methods Twelve out of 98 initially screened hospitalized SARS-CoV-2-positive patients were included in this study. Intraoral viral load was determined by RT-PCR at baseline, whereupon patients had to gargle mouth and throat with 20 mL of 1% hydrogen peroxide for 30 s. After 30 min, a second examination of intraoral viral load was performed by RT-PCR. Furthermore, virus culture was performed for specimens exhibiting viral load of at least 103 RNA copies/mL at baseline. Results Ten out of the 12 initially included SARS-CoV-2-positive patients completed the study. The hydrogen peroxide mouthrinse led to no significant reduction of intraoral viral load. Replicating virus could only be determined from one baseline specimen. Conclusion A 1% hydrogen peroxide mouthrinse does not reduce the intraoral viral load in SARS-CoV-2-positive subjects. However, virus culture did not yield any indication on the effects of the mouthrinse on the infectivity of the detected RNA copies. Clinical relevance The recommendation of a preprocedural mouthrinse with hydrogen peroxide before intraoral procedures is questionable and thus should not be supported any longer, but strict infection prevention regimens are of paramount importance. Trial registration German Clinical Trials Register (ref. DRKS00022484)

scholarly journals Direct Quantitation of SARS-CoV-2 Using Droplet Digital PCR in Suspected Samples With Very Low Viral Load

2021 ◽  
Author(s):  
Michela Deiana ◽  
Chiara Piubelli ◽  
Antonio Mori ◽  
Gian Paolo Chiecchi ◽  
Giulia La Marca ◽  
...  
Keyword(s):  
Viral Load ◽  
Real Time ◽  
False Negative ◽  
Digital Pcr ◽  
Droplet Digital Pcr ◽  
Hospitalized Patients ◽  
Lower Sensitivity ◽  
Rt Pcr ◽  
Viral Genes ◽  
Viral Target

Background: The reference test for SARS-CoV-2 detection is the reverse transcriptase real time PCR (real time RT-PCR). However, evidences reported that real time RT-PCR has a lower sensitivity compared with the droplet digital PCR (ddPCR) leading to possible false negative in low viral load cases. Methods: We used ddPCR for viral genes N1 and N2 on 20 negative (no detection) samples from symptomatic hospitalized COVID-patients presenting fluctuating real time RT-PCR results and 10 suspected samples (Ct value>35) from asymptomatic not hospitalized subjects. Results: ddPCR performed on RNA revealed 65% of positivity for at least one viral target in the hospitalized patients group of samples (35% for N1 and N2, 10% only for N1 and 20% only for N2) and 50% in the suspected cases (30% for N1 and N2, while 20% only for N2). On hospitalized patients’ samples, we applied also a direct ddPCR approach on the swab material, achieving an overall positivity of 83%. Conclusion: ddPCR, in particular the direct quantitation on swabs, shows a sensitivity advantage for the SARS-CoV-2 identification and may be useful to reduce the false negative diagnosis, especially for low viral load suspected samples.

scholarly journals SARS-CoV-2 viral RNA is not viral load

2021 ◽  
Author(s):  
Yannis Michalakis ◽  
Mircea T Sofonea ◽  
Samuel Alizon
Keyword(s):  
Viral Load ◽  
Genetic Factors ◽  
Expression Profiles ◽  
A Priori ◽  
Disease Stage ◽  
Rt Pcr ◽  
Mild Disease ◽  
Viral Genes ◽  
Quantitative Analyses ◽  
Virus Biology

Several recent studies used results of SARS-CoV-2 RT-qPCR, Ct (threshold cycle), as proxies of viral load1. Unfortunately, an important aspect of this virus’ biology is neglected: Coronaviruses being (+)ssRNA viruses the form of RNA they use for replication is identical to the form used for transcription. It is therefore not obvious which process, replication or transcription, is quantified by RT-qPCR. To make matters more complicated, Coronaviruses produce several kinds of mRNA, genomic (= full size) and subgenomic (carrying only some genes), hence modulating their gene expression1. As shown by Finkel et al. the different mRNAs of SARS-CoV-2 occur at different densities in cell cultures. Because of their location on the viral genome the different targets of RT-qPCR are differentially affected, some being carried by more types of mRNA than others. Further, gene expression being affected by environmental and genetic factors, the quantity of RNA revealed by RT-qPCR may consequently vary due to differences in replication rates, in expression rates, or in both. It is thus unclear how good a proxy of viral load Ct values are, or what differences in Ct values may reflect.Even though the process underlying them is poorly characterized, and despite additional known biases in sample quality and RT-PCR protocols, quantitative analyses of Ct may nevertheless be highly informative e.g. in allowing to detect patterns in ‘levels of RNA’ in patients with different properties (gender, age, severe vs. mild disease, stage of infection) or in allowing to relate these patterns to epidemic properties in populations. For example, given that a priori replication levels should be the same for all genes of these monopartite viruses, differences in Ct among markers lying in different viral genes for should reflect different expression profiles. Such observations could thus help reveal interesting, and potentially epidemiologically significant, variations e.g. among SARS-CoV-2 variants.

scholarly journals Lower nasopharyngeal viral load during the latest phase of COVID-19 pandemic in a Northern Italy University Hospital

2020 ◽  
Vol 58 (9) ◽  
pp. 1573-1577 ◽  
Author(s):  
Nicola Clementi ◽  
Roberto Ferrarese ◽  
Marco Tonelli ◽  
Virginia Amato ◽  
Sara Racca ◽  
...  
Keyword(s):  
Viral Load ◽  
Pilot Study ◽  
Pcr Amplification ◽  
Clinical Severity ◽  
University Hospital ◽  
Rt Pcr ◽  
Viral Loads ◽  
Viral Load Data ◽  
The Mean ◽  
Polymerase Chain

AbstractObjectivesA milder clinical course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been anecdotally reported over the latest phase of COVID-19 pandemic in Italy. Several factors may contribute to this observation, including the effect of lockdown, social distancing, lower humidity, lower air pollution, and potential changes in the intrinsic pathogenicity of the virus. In this regard, the clinical severity of COVID-19 could be attenuated by mutations in SARS-CoV-2 genome that decrease its virulence, as well as by lower virus inocula.MethodsIn this pilot study, we compared the reverse transcription polymerase chain reaction (RT-PCR) amplification profile of 100 nasopharyngeal swabs consecutively collected in April, during the peak of SARS-CoV-2 epidemic, to that of 100 swabs collected using the same procedure in May.ResultsThe mean Ct value of positive samples collected in May was significantly higher than that of samples collected in the previous period (ORF 1a/b gene: 31.85 ± 0.32 vs. 28.37 ± 0.5, p<0.001; E gene: 33.76 ± 0.38 vs. 29.79 ± 0.63, p<0.001), suggesting a lower viral load at the time of sampling. No significant differences were observed between male and females in the two periods, whilst higher viral loads were found in (i) patients over 60-years old, and (ii) patients that experienced severe COVID-19 during the early stages of the pandemic.ConclusionsThis pilot study prompts further investigation on the correlation between SARS-CoV-2 load and different clinical manifestation of COVID-19 during different phases of the pandemic. Laboratories should consider reporting quantitative viral load data in the molecular diagnosis of SARS-CoV-2 infection.

scholarly journals Viral Dynamics and Real-Time RT-PCR Ct Values Correlation with Disease Severity in COVID-19

Diagnostics ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1091
Author(s):  
Ali A. Rabaan ◽  
Raghavendra Tirupathi ◽  
Anupam A Sule ◽  
Jehad Aldali ◽  
Abbas Al Mutair ◽  
...  
Keyword(s):  
Viral Load ◽  
Real Time ◽  
Disease Severity ◽  
False Negative ◽  
Influential Factors ◽  
Confirmatory Test ◽  
Acid Extraction ◽  
Rt Pcr ◽  
Viral Kinetics ◽  
Ct Value

Real-time RT-PCR is considered the gold standard confirmatory test for coronavirus disease 2019 (COVID-19). However, many scientists disagree, and it is essential to understand that several factors and variables can cause a false-negative test. In this context, cycle threshold (Ct) values are being utilized to diagnose or predict SARS-CoV-2 infection. This practice has a significant clinical utility as Ct values can be correlated with the viral load. In addition, Ct values have a strong correlation with multiple haematological and biochemical markers. However, it is essential to consider that Ct values might be affected by pre-analytic, analytic, and post-analytical variables such as collection technique, specimen type, sampling time, viral kinetics, transport and storage conditions, nucleic acid extraction, viral RNA load, primer designing, real-time PCR efficiency, and Ct value determination method. Therefore, understanding the interpretation of Ct values and other influential factors could play a crucial role in interpreting viral load and disease severity. In several clinical studies consisting of small or large sample sizes, several discrepancies exist regarding a significant positive correlation between the Ct value and disease severity in COVID-19. In this context, a revised review of the literature has been conducted to fill the knowledge gaps regarding the correlations between Ct values and severity/fatality rates of patients with COVID-19. Various databases such as PubMed, Science Direct, Medline, Scopus, and Google Scholar were searched up to April 2021 by using keywords including “RT-PCR or viral load”, “SARS-CoV-2 and RT-PCR”, “Ct value and viral load”, “Ct value or COVID-19”. Research articles were extracted and selected independently by the authors and included in the present review based on their relevance to the study. The current narrative review explores the correlation of Ct values with mortality, disease progression, severity, and infectivity. We also discuss the factors that can affect these values, such as collection technique, type of swab, sampling method, etc.

scholarly journals Performance of Self-Collected Saliva Testing Compared with Nasopharyngeal Swab Testing for the Detection of SARS-CoV-2

Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 895
Author(s):  
Florence Carrouel ◽  
Martine Valette ◽  
Hervé Perrier ◽  
Maude Bouscambert-Duchamp ◽  
Claude Dussart ◽  
...  
Keyword(s):  
Viral Load ◽  
Quantitative Pcr ◽  
Statistical Analyses ◽  
Fair Agreement ◽  
Quantitative Detection ◽  
Nasopharyngeal Swab ◽  
Rt Pcr ◽  
Noninvasive Techniques ◽  
Concordance Probability ◽  
Salivary Test

The aim of this study was to determine whether self-collected pure saliva (SCPS) is comparable to nasopharyngeal (NP) swabs in the quantitative detection of SARS-CoV-2 by RT-PCR in asymptomatic, mild patients with confirmed COVID-19. Thirty-one patients aged from 18 to 85 years were included between 9 June and 11 December 2020. A SCPS sample and a NP sample were taken for each patient. Quantitative PCR was performed to detect SARS-CoV-2 viral load. Results of SCPS vs NP samples testing were compared. Statistical analyses were performed. Viral load was significantly correlated (r = 0.72). The concordance probability was estimated at 73.3%. In symptomatic adults, SCPS performance was similar to that of NP swabs (Percent Agreement = 74.1%; p = 0.11). Thus, the salivary test based on pure oral saliva samples easily obtained by noninvasive techniques has a fair agreement with the nasopharyngeal one in asymptomatic, mild patients with a confirmed diagnosis of COVID-19.

scholarly journals Knowledge, Attitudes, Behaviors of Women Related to Pregnancy, and Early Childhood Caries Prevention: A Cross-Sectional Pilot Study

2021 ◽  
Vol 12 ◽  
pp. 215013272110133
Author(s):  
Neel Shimpi ◽  
Ingrid Glurich ◽  
Catherine Maybury ◽  
Min Qi Wang ◽  
Kazumasa Hashimoto ◽  
...  
Keyword(s):  
Oral Health ◽  
Pilot Study ◽  
Health Education ◽  
Survey Study ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Health Maintenance ◽  
Significance Level ◽  
Study Results ◽  
And Behaviors

Objective Health education interventions during pregnancy can influence maternal oral health (OH), maternal OH-behaviors and children’s OH. Interventions that can be delivered at anytime and anywhere, for example mobile-health (mHealth) provides an opportunity to address challenges of health education and support activation of women in underserved and rural communities to modify their health behavior. This pilot study was undertaken as a part of a mHealth initiative to determine knowledge, attitudes, and behaviors related to pregnancy and ECC prevention among women attending obstetrics/gynecology (OB/GYN) practices at a large rurally-based clinic. Methods A cross-sectional survey study was voluntarily engaged by women (n = 191) aged 18 to 59 years attending OB/GYN visits, over a 3-week period from 12/2019 to 1/2020. Survey results were analyzed applying descriptive statistics, X2 and Fisher’s Exact tests. The significance level was set at P < .0001 for all analyses. Results Approximately half of respondents were between 18 and 29 years (53%), had a college degree (55%), and 100% reported cell phone use. Whereas 53% and 31%, respectively, indicated that they were “somewhat” or “very” sure of how to prevent ECC in their children, only 9% recognized evidence of early decay and 30% did not know the purpose of fluoride. Overall, only 27% of participants correctly answered the knowledge-based questions. Further, only 57% reported their provider explained things in a way that was easy to understand. Only 24% reported seeing a dentist during their current pregnancy. Conclusions Study results suggested potential gaps in knowledge and behaviors related to ECC prevention and provided baseline data to inform future interventions to improve ECC prevention practices. Notably, majority of participants used their cell phones for making medical/dental appointments and reported using their phones to look up health-related information. This demographic represents a potentially receptive target for mHealth approaches to improve understanding of oral health maintenance during pregnancy and ECC prevention.

scholarly journals Automated Low Cost Method of Quantification of Hepatitis C Virus

2015 ◽  
Vol 14 (3) ◽  
pp. 247-253
Author(s):  
Faiz MMT Marikar ◽  
Dammika Senevirathna ◽  
Neil Fernandopulle
Keyword(s):  
Viral Load ◽  
Hepatitis C ◽  
Blood Donors ◽  
Low Cost ◽  
Medical Science ◽  
Simultaneous Detection ◽  
Plasma Samples ◽  
Rt Pcr ◽  
Viral Genomes ◽  
Post Therapy

This paper describes the development of a Dig-dUTP based multiplex real time RT-PCR for the simultaneous detection of HCV viral amount in plasma samples. Viral genomes were identified in the same sample by Dig-dUTP PCR 216 bp region. Analysis of known scalar concentrations of reference plasma indicated that the multiplex procedure detects at least 500 copies/ml of HCV. In addition, we also assayed HCV viral load in eighty co-infected patients and in fifteen blood donors, confirming the sensitivity and specificity of the assay. This method may represent a useful alternative method for the detection of HCV co-infection, reliable for a rapid and relatively inexpensive screening of blood donors. The assay may be used to determine post-therapy viral clearance.Bangladesh Journal of Medical Science Vol.14(3) 2015 p.247-253

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