scholarly journals Effectiveness of BNT162b2 and mRNA-1273 covid-19 vaccines against symptomatic SARS-CoV-2 infection and severe covid-19 outcomes in Ontario, Canada: test negative design study

BMJ ◽  
2021 ◽  
pp. n1943 ◽  
Author(s):  
Hannah Chung ◽  
Siyi He ◽  
Sharifa Nasreen ◽  
Maria E Sundaram ◽  
Sarah A Buchan ◽  
...  
Keyword(s):  
Hospital Admission ◽  
Clinical Characteristics ◽  
Hospital Admissions ◽  
Vaccine Effectiveness ◽  
Community Dwelling ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Design Study ◽  
Symptomatic Infection ◽  
Polymerase Chain

AbstractObjectiveTo estimate the effectiveness of mRNA covid-19 vaccines against symptomatic infection and severe outcomes (hospital admission or death).DesignTest negative design study.SettingOntario, Canada between 14 December 2020 and 19 April 2021.Participants324 033 community dwelling people aged ≥16 years who had symptoms of covid-19 and were tested for SARS-CoV-2.InterventionsBNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) vaccine.Main outcome measuresLaboratory confirmed SARS-CoV-2 by reverse transcription polymerase chain reaction (RT-PCR) and hospital admissions and deaths associated with SARS-CoV-2 infection. Multivariable logistic regression was adjusted for personal and clinical characteristics associated with SARS-CoV-2 and vaccine receipt to estimate vaccine effectiveness against symptomatic infection and severe outcomes.ResultsOf 324 033 people with symptoms, 53 270 (16.4%) were positive for SARS-CoV-2 and 21 272 (6.6%) received at least one dose of vaccine. Among participants who tested positive, 2479 (4.7%) were admitted to hospital or died. Vaccine effectiveness against symptomatic infection observed ≥14 days after one dose was 60% (95% confidence interval 57% to 64%), increasing from 48% (41% to 54%) at 14-20 days after one dose to 71% (63% to 78%) at 35-41 days. Vaccine effectiveness observed ≥7 days after two doses was 91% (89% to 93%). Vaccine effectiveness against hospital admission or death observed ≥14 days after one dose was 70% (60% to 77%), increasing from 62% (44% to 75%) at 14-20 days to 91% (73% to 97%) at ≥35 days, whereas vaccine effectiveness observed ≥7 days after two doses was 98% (88% to 100%). For adults aged ≥70 years, vaccine effectiveness estimates were observed to be lower for intervals shortly after one dose but were comparable to those for younger people for all intervals after 28 days. After two doses, high vaccine effectiveness was observed against variants with the E484K mutation.ConclusionsTwo doses of mRNA covid-19 vaccines were observed to be highly effective against symptomatic infection and severe outcomes. Vaccine effectiveness of one dose was observed to be lower, particularly for older adults shortly after the first dose.

scholarly journals Characteristics of recovered COVID-19 patients with recurrent positive RT-PCR findings in Wuhan, China: a retrospective study

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Tie-Jun Shui ◽  
Chao Li ◽  
Hong-bing Liu ◽  
Xiaohua Chen ◽  
Bi-ke Zhang
Keyword(s):  
Polymerase Chain Reaction ◽  
Retrospective Study ◽  
Clinical Characteristics ◽  
Throat Swab ◽  
Antibody Detection ◽  
Controlled Trials ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Polymerase Chain

Abstract Background Two months after the outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China, tens of thousands of hospitalized patients had recovered, and little is known about the follow-up of the recovered patients. Methods The clinical characteristics, reverse transcriptase-polymerase chain reaction (RT-PCR) results from throat swab specimens and the results of serological COVID-19 rapid diagnostic test (RDT) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were retrospectively reviewed for a total of 758 recovered patients who were previously hospitalized in 17 hospitals and quarantined at 32 rehabilitation stations in Wuhan, China. Results In total, 59 patients (7.78%) had recurrent positive findings for COVID-19 on RT-PCR from throat swabs. With regard to antibody detection, 50/59 (84.75%) and 4/59 (6.78%) patients had positive IgG or dual positive IgG/IgM RDT results, respectively. Conclusions Some patients who had been quarantined and had subsequently recovered from COVID-19 had recurrent positive RT-PCR results for SARS-CoV-2, and the possibility of transmission of the virus by recovered patients needs further investigation. Trial registration Current Controlled Trials ChiCTR2000033580, Jun 6th 2020. Retrospectively registered.

scholarly journals Clinical characteristics and viral load dynamics of COVID-19 in a mildly or moderately symptomatic outpatient sample

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258970
Author(s):  
Amanda Caplan ◽  
Kelly W. Bates ◽  
Carla Brioni ◽  
Aileen Santos ◽  
Linda M. Sabatini ◽  
...  
Keyword(s):  
Viral Load ◽  
Symptom Onset ◽  
Clinical Characteristics ◽  
Symptom Duration ◽  
Test Results ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
Antibody Tests ◽  
Pcr Test

Background Studies of outpatients with mild or moderate COVID-19 are uncommon. We studied: 1) association of symptoms with reverse transcriptase polymerase chain reaction (RT-PCR) test results; and 2) association of initial RT-PCR cycle threshold (Ct) in relation to duration of RT-PCR positivity in outpatients with mild or moderate COVID-19. Methods This was a cohort study of outpatients with confirmed COVID-19 and at least one symptom. Participants had repeat nasopharyngeal swabs and symptom checklists every 3–5 days until two consecutive RT-PCR tests were negative. RT-PCR tests were used to assess viral load. Antibody tests for COVID-19 were performed at 2 weeks, 4 weeks, and 8 weeks after symptom onset. Results Twenty-five patients (nine females) were enrolled, ranging in age from 19–58 (median age 28 years). All patients reported at least one symptom, with a median of six symptoms per patient. Symptoms persisted for 6–67 days (median duration 18 days). In all 25 patients, blood samples collected a median of 13 days after symptom onset were positive for SARS-CoV-2 antibodies in 15 (60%). After a median of 28 days following symptom onset, 23/23 patients with available samples tested positive for antibodies. The longest duration of positive RT-PCR test was 49 days from first positive PCR test (Mean = 27.4, SD = 12.5, Median = 24). Initial Ct was significantly associated with longer duration (β = -1.3, SE = 0.3, p<0.01 per 1 cycle higher) of RT-PCR positivity. Conclusions In mildly or moderately ill COVID-19 outpatients, RT-PCT tests remained positive for as long as 49 days and test positivity and symptom duration correlated with initial viral load.

scholarly journals Low Influenza Vaccine Effectiveness Against A(H3N2)-Associated Hospitalizations in 2016–2017 and 2017–2018 of the Hospitalized Adult Influenza Vaccine Effectiveness Network (HAIVEN)

2020 ◽  
Author(s):  
Emily T Martin ◽  
Caroline Cheng ◽  
Joshua G Petrie ◽  
Elif Alyanak ◽  
Manjusha Gaglani ◽  
...  
Keyword(s):  
Influenza Vaccine ◽  
Influenza A ◽  
Vaccine Virus ◽  
Vaccine Effectiveness ◽  
Point Estimate ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
H3n2 Vaccine ◽  
Antigenic Epitopes

Abstract Background The 2016–2017 and 2017–2018 influenza seasons were notable for the high number of hospitalizations for influenza A(H3N2) despite vaccine and circulating strain match. Methods We evaluated vaccine effectiveness (VE) against hospitalization in the test-negative HAIVEN study. Nasal-throat swabs were tested by quantitative reverse transcription polymerase chain reaction (RT-PCR) for influenza and VE was determined based on odds of vaccination by generalized estimating equations. Vaccine-specific antibody was measured in a subset of enrollees. Results A total of 6129 adults were enrolled from 10 hospitals. Adjusted VE against A(H3N2) was 22.8% (95% confidence interval [CI], 8.3% to 35.0%), pooled across both years and 49.4% (95% CI, 34.3% to 61.1%) against B/Yamagata. In 2017–2018, the A(H3N2) VE point estimate for the cell-based vaccine was 43.0% (95% CI, −36.3% to 76.1%; 56 vaccine recipients) compared to 24.0% (95% CI, 3.9% to 39.9%) for egg-based vaccines. Among 643 with serology data, hemagglutinin antibodies against the egg-based A(H3N2) vaccine strain were increased in influenza-negative individuals. Conclusions Low VE for the A/Hong Kong/4801/2014 vaccine virus in both A(H3N2) seasons emphasizes concerns for continued changes in H3N2 antigenic epitopes, including changes that may impact glycosylation and ultimately reduce VE.

1504: Molecular Diagnosis and Staging of Prostate Cancer Using Clusterin in Real Time Reverse Transcription Polymerase Chain Reaction (RT-PCR)

2006 ◽  
Vol 175 (4S) ◽  
pp. 485-486
Author(s):  
Sabarinath B. Nair ◽  
Christodoulos Pipinikas ◽  
Roger Kirby ◽  
Nick Carter ◽  
Christiane Fenske
Keyword(s):  
Prostate Cancer ◽  
Polymerase Chain Reaction ◽  
Real Time ◽  
Molecular Diagnosis ◽  
Reverse Transcription ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Polymerase Chain

Expression of Platelet Membrane Glycoprotein V in Human Megakaryocytes and Megakaryocytic Cell Lines: A Study Using a Novel Monoclonal Antibody against GPV

1994 ◽  
Vol 72 (05) ◽  
pp. 762-769 ◽  
Author(s):  
Toshiro Takafuta ◽  
Kingo Fujirmura ◽  
Hironori Kawano ◽  
Masaaki Noda ◽  
Tetsuro Fujimoto ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Cell Lines ◽  
Immunohistochemical Analysis ◽  
Specific Protein ◽  
Platelet Membrane ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Flow Cytometric ◽  
Polymerase Chain ◽  
Megakaryocytic Cell

SummaryGlycoprotein V (GPV) is a platelet membrane protein with a molecular weight of 82 kD, and one of the leucine rich glycoproteins (LRG). By reverse transcription-polymerase chain reaction (RT-PCR), GPV cDNA was amplified from mRNA of platelets and megakaryocytic cell lines. However, since there are few reports indicating whether GPV protein is expressed in megakaryocytes as a lineage and maturation specific protein, we studied the GPV expression at the protein level by using a novel monoclonal antibody (1D9) recognizing GPV. Flow cytometric and immunohistochemical analysis indicated that GPV was detected on the surface and in the cytoplasm of only the megakaryocytes in bone marrow aspirates. In a megakaryocytic cell line UT-7, GPV antigen increased after treatment with phorbol-12-myri-state-13-acetate (PMA). These data indicate that only megakaryocytes specifically express the GPV protein among hematopoietic cells and that the expression of GPV increases with differentiation of the megakaryocyte as GPIb-IX complex.

Polymerase chain reaction amplification and typing of rotavirus in environmental samples

1995 ◽  
Vol 31 (5-6) ◽  
pp. 371-374 ◽  
Author(s):  
R. Gajardo ◽  
R. M. Pintó ◽  
A. Bosch
Keyword(s):  
Polymerase Chain Reaction ◽  
Environmental Samples ◽  
Polymerase Chain Reaction Amplification ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Pcr Assay ◽  
Group A ◽  
Reaction Amplification ◽  
Stool Specimens ◽  
Polymerase Chain

A reverse transcription polymerase chain reaction (RT-PCR) assay is described that has been developed for the detection and serotyping of group A rotavirus in stool specimens and concentrated and non-concentrated sewage specimens.

scholarly journals Machine Learning Prediction of SARS-CoV-2 Polymerase Chain Reaction Results with Routine Blood Tests

2020 ◽  
Author(s):  
Thomas Tschoellitsch ◽  
Martin Dünser ◽  
Carl Böck ◽  
Karin Schwarzbauer ◽  
Jens Meier
Keyword(s):  
Machine Learning ◽  
Polymerase Chain Reaction ◽  
Characteristic Curve ◽  
Cohort Analysis ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Blood Tests ◽  
Routine Blood ◽  
Machine Learning Model ◽  
Polymerase Chain

Abstract Objective The diagnosis of COVID-19 is based on the detection of SARS-CoV-2 in respiratory secretions, blood, or stool. Currently, reverse transcription polymerase chain reaction (RT-PCR) is the most commonly used method to test for SARS-CoV-2. Methods In this retrospective cohort analysis, we evaluated whether machine learning could exclude SARS-CoV-2 infection using routinely available laboratory values. A Random Forests algorithm with 1353 unique features was trained to predict the RT-PCR results. Results Out of 12,848 patients undergoing SARS-CoV-2 testing, routine blood tests were simultaneously performed in 1528 patients. The machine learning model could predict SARS-CoV-2 test results with an accuracy of 86% and an area under the receiver operating characteristic curve of 0.90. Conclusion Machine learning methods can reliably predict a negative SARS-CoV-2 RT-PCR test result using standard blood tests.

scholarly journals Report of a Confirmed SARS-CoV-2 Positive Newborn after Delivery Despite Negative SARS-CoV-2 Testing on Both Parents

2021 ◽  
Vol 11 (02) ◽  
pp. e80-e83
Author(s):  
Benjamin R. Harding ◽  
Farha Vora
Keyword(s):  
Neonatal Intensive Care ◽  
Community Hospital ◽  
Material Testing ◽  
Term Infant ◽  
Accurate Diagnosis ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Potential Case ◽  
Polymerase Chain ◽  
Negative Material

AbstractWe present a case of a term infant born to an asymptomatic mother at a community hospital who required transfer to a local neonatal intensive care unit (NICU) immediately after birth for respiratory distress. The infant was tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at 24 hours of life by reverse transcription polymerase chain reaction (RT-PCR) testing due to the absence of prenatal maternal COVID-19 testing and was found to be positive for SARS-CoV-2 at that time. A second RT-PCR test was obtained on the infant on day of life (DOL) 4 and was also positive, confirming an accurate diagnosis of COVID-19 disease in the infant. Both the mother and father remained asymptomatic and concomitantly tested negative for SARS-CoV-2 on two separate occasions. The infant subsequently clinically improved and was discharged without any complications. This case raises the potential concern for two unreported newborn issues related to COVID-19. First, the potential unreliability of negative maternal COVID-19 testing surrounding the time of delivery as it relates to routine newborn testing and isolation needs, and second, if the negative material testing was accurate, this raises the concern for a potential case of nosocomial COVID-19 infection within the first 24 hours of life.

scholarly journals A meta-analysis of accuracy and sensitivity of chest CT and RT-PCR in COVID-19 diagnosis

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Fatemeh Khatami ◽  
Mohammad Saatchi ◽  
Seyed Saeed Tamehri Zadeh ◽  
Zahra Sadat Aghamir ◽  
Alireza Namazi Shabestari ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Reverse Transcriptase ◽  
Ct Scan ◽  
Predictive Value ◽  
Meta Analysis ◽  
Chest Ct ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
Chest Ct Scan

AbstractNowadays there is an ongoing acute respiratory outbreak caused by the novel highly contagious coronavirus (COVID-19). The diagnostic protocol is based on quantitative reverse-transcription polymerase chain reaction (RT-PCR) and chests CT scan, with uncertain accuracy. This meta-analysis study determines the diagnostic value of an initial chest CT scan in patients with COVID-19 infection in comparison with RT-PCR. Three main databases; PubMed (MEDLINE), Scopus, and EMBASE were systematically searched for all published literature from January 1st, 2019, to the 21st May 2020 with the keywords "COVID19 virus", "2019 novel coronavirus", "Wuhan coronavirus", "2019-nCoV", "X-Ray Computed Tomography", "Polymerase Chain Reaction", "Reverse Transcriptase PCR", and "PCR Reverse Transcriptase". All relevant case-series, cross-sectional, and cohort studies were selected. Data extraction and analysis were performed using STATA v.14.0SE (College Station, TX, USA) and RevMan 5. Among 1022 articles, 60 studies were eligible for totalizing 5744 patients. The overall sensitivity, specificity, positive predictive value, and negative predictive value of chest CT scan compared to RT-PCR were 87% (95% CI 85–90%), 46% (95% CI 29–63%), 69% (95% CI 56–72%), and 89% (95% CI 82–96%), respectively. It is important to rely on the repeated RT-PCR three times to give 99% accuracy, especially in negative samples. Regarding the overall diagnostic sensitivity of 87% for chest CT, the RT-PCR testing is essential and should be repeated to escape misdiagnosis.

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