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2021 ◽  
Author(s):  
Peter Maher ◽  
Carl Nelson ◽  
David Dockweiler

Abstract Running two compression set tools in a single wellbore clean out string, typically a bypass tool and negative test packer, has been a significant industry challenge to operate reliably. The need for running these types of tools is generally driven by the need to perform a negative test on a liner top and achieve high flow rates necessary to hydraulically remove debris from the well. Combining these operations into a single run is an increasingly common method to reduce rig time and cost for the operator. Tools to perform this type of operation are generally available from many service providers, however difficulties and challenges arise when trying to manipulate two different tools in the same string that function by the same compression set method. These operations do have a history that is partially successful, however on a long term basis reliability is generally considered poor by most operators, as a failure to manipulate the tools correctly can result in a failed run and a trip out of the hole. This paper discusses the development and successful field deployment of a system of two compression set tools to address this specific challenge while improving reliability over existing solutions.


2021 ◽  
pp. 003335492110492
Author(s):  
Miranda S. Moore ◽  
Angelica Bocour

Objective Curative treatments for hepatitis C virus (HCV) infection are available, but access and barriers to treatment can delay initiation. We investigated the time to first negative RNA test result among people with HCV infection and examined differences by homeless status and whether people were tested at a correctional facility or substance use treatment facility. Methods We used surveillance data to identify New York City residents first reported with HCV infection during January 1, 2015–December 31, 2018, with ≥1 positive RNA test result during January 1, 2015–November 1, 2019. We used Kaplan–Meier survival analysis to determine the time from the first positive RNA test result to the first negative RNA test result, with right-censoring at date of death or November 1, 2019. We determined substance use treatment, incarceration, or homelessness by ordering facility name and address or from patient residential address. Results Of 13 952 people with an HCV RNA–positive test result first reported during 2015-2018, 6947 (49.8%) subsequently received an RNA-negative test result. Overall, 25% received an RNA-negative test result within 208 (95% CI, 200-216) days and 50% within 902 (95% CI, 841-966) days. Homelessness, incarceration, or substance use treatment was indicated for 4304 (30.9%) people, among whom 25% received an RNA-negative test result within 469 (95% CI, 427-520) days and <50% received an RNA-negative test result during the study period. Conclusions Efforts to connect people to treatment should occur soon after diagnosis, especially for people who could benefit from hepatitis C care coordination.


Author(s):  
Alessandro Brancatella ◽  
Nicola Viola ◽  
Grazia Rutigliano ◽  
Daniele Sgrò ◽  
Ferruccio Santini ◽  
...  

Abstract Context Acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been related to subacute thyroiditis (SAT). Objectives To compare SAT cases at the time of SARS-CoV-2 pandemic to those observed in the previous years. Methods A cross-sectional, retrospective study was conducted at the Endocrinology Unit of University-Hospital of Pisa, Italy. We included all patients observed from January 2016 to December 2020 because of an untreated SAT, who had developed the disease within 15 days prior to the visit. SAT cases from 2016 to 2019 (N=152) are referred as “pre-SARS-CoV-2”, while 2020 SAT patients are classified as “pos-SARS-CoV-2” (N=18) or “neg-SARS-CoV-2” (N=28), according to positive or negative test for SARS-CoV-2 performed up to 45 days from SAT onset. Results While during the years 2016-2019 most SAT cases were observed in the 3 rd quarter, in 2020 two peaks, superimposable to the outbreaks of SARS-CoV-2 pandemic of the 2 nd and the 4 th quarters, were seen. In the 2 nd and the 4 th quarters of 2020 we observed higher levels of free thyroxine (FT4), C-reactive protein (CRP) and thyroglobulin (Tg) compared to the same quarters of the years 2016-2019. Pos-SARS-CoV-2 had higher FT4 (28.4 vs 24.1 nmol/L), CRP (8.5 vs 3.6 mg/L) and Tg (155 vs 60 μg/L) (P&lt;0.05 for all) and resulted more frequently in hypothyroidism (13/15 vs 30/152 at 3 months) (P&lt;0.001) than to pre-SARS-CoV-2 patients. Neg-SARS-CoV-2 patients showed a clinical picture intermediate between the other two groups. Conclusions SARS-CoV-2 pandemic has caused a shift in the annual timing and severity of SAT cases.


2021 ◽  
Vol 1 (S1) ◽  
pp. s56-s56
Author(s):  
Antigone Kraft ◽  
Jessica Ridgway ◽  
Erica Mackenzie ◽  
Aniruddha Hazra ◽  
Maggie Collison ◽  
...  

Background: At our institution, the concern for false-negative nasopharyngeal testing for SARS-CoV-2 at the onset of illness led to a general policy of retesting inpatients at 48 hours. For such patients, 2 negative SARS-CoV-2 PCR test results were required prior to discontinuation of COVID-19 control precautions. To assess the utility of routine repeat testing We analyzed patients presenting to our hospital who initially tested negative for SARS-CoV-2 but were found to be positive on repeated testing. Methods: All inpatients with symptoms concerning for COVID-19 were tested via nasopharyngeal sample for SARS-CoV-2 by PCR on admission. Patients with continued symptoms and no alternative diagnosis were retested 48 hours later. Testing was performed using either the Roche cobas SARS-CoV-2 RT-PCR assay or the Cepheid Xpert Xpress SARS-CoV-2 test. Between March 17, 2020, and May 10, 2020, we retrospectively analyzed data from patients with false-negative SARS-CoV-2 PCR test results who were subsequently confirmed positive 48 hours later. We evaluated demographic information, days since symptom onset, symptomatology, chest imaging, vital sign trends, and the overall clinical course of each patient. Results: During the study period, 14,683 tests were performed, almost half (n = 7,124) were performed through the ED and in the inpatient setting. Of 2,283 patients who tested positive for SARS-CoV-2, only 19 (0.01%) initially tested negative. Patients with initial false-negative test results presented with symptoms that ranged from fever and dyspnea to fatigue and vomiting. Notably, few patients presented “early” in their disease (median, 6 days; range, 0–10 days). However, patients with initial false-negative PCR test results did seem to have consistent imaging findings, specifically bilateral bibasilar ground glass opacities on chest radiograph or computed tomography scan. Conclusions: Among inpatients with COVID-19, we found a very low rate of initial false-negative SARS-CoV-2 PCR test results, which were not consistently related to premature testing. We also identified common radiographic findings among patients with initially false-negative test results, which could be useful in triaging patients who may merit retesting. Based on these data, we revised our existing clearance criteria to allow for single-test removal of COVID-19 precautions. Evaluating subsequent reduction in unnecessary testing is difficult given changing community prevalence, increased census, and increased opening to elective procedures. However, given the significant percentage of ED and inpatient testing, removal of repeated testing has likely resulted in a reduction of several thousand unnecessary COVID-19 tests monthly.Funding: NoDisclosures: None


2021 ◽  
Vol 71 (708) ◽  
pp. 298-299
Author(s):  
Stephen H Bradley ◽  
Brian D Nicholson ◽  
Garth Funston

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1133
Author(s):  
Ivan Brukner ◽  
Alex Resendes ◽  
Shaun Eintracht ◽  
Andreas I. Papadakis ◽  
Matthew Oughton

Sample Adequacy Control (SAC) has critical analytical, clinical and epidemiological value that increases confidence in a negative test result. The SAC is an integral qPCR assay control, which ensures that all pre-analytical and analytical steps are adequate for accurate testing and reporting. As such, a negative SAC with a negative result on pathogen screen specifies that the result should be reported as inconclusive instead of negative. Despite this, many regulatory approved tests do not incorporate SAC into their assay design. Herein, we emphasize the universal value of SAC and offer for the first time, a simple technical strategy to introduce non-competitive SAC which does not interfere with the limit of detection for the screened pathogen. Integration of SAC can provide key benefits towards identifying, isolating, quarantining and contact tracing infected individuals and in turn can improve worldwide efforts in infection control.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Marit Østlyngen Riibe ◽  
Sveinung Wergeland Sørbye ◽  
Gunnar Skov Simonsen ◽  
Arnfinn Sundsfjord ◽  
Josef Ekgren ◽  
...  

Abstract Background/objective Having a 30-year follow-up of a cohort of women tested for HPV is a unique opportunity to further study long-term risk of CIN3+. The study objective was to compare HPV status at baseline with the risk of CIN3+ in the follow-up period of 30 years. Methods All women (n = 642) referred to the HPV outpatient clinic at the University Hospital of North Norway (UNN) in 1990–1992, with an HPV test at baseline, were included in a prospective cohort. HPV-testing was performed by two different HPV-DNA tests, and genotypes 6, 11, 16, 18, 31 and 33 were identified. High-risk (HR) HPV genotypes (16, 18, 31 and 33) were classified as HPV positive, whereas low-risk (LR) genotypes (6 and 11) in addition to absent HPV were classified as HPV negative. A single cohort in which women were classified for their HPV status underwent follow-up prospectively to the last time-point of observation of 30 years. Results During follow-up, 148 (148/642) cases of CIN3+ were detected, of whom 70.3% (104/148) were HPV positive and 29.7% (44/148) were HPV negative at baseline. The proportions of women who developed CIN3+ following a positive and a negative test were 46.6% (104/223) and 10.5% (44/419), respectively. Most cases of CIN3+ were seen shortly after the baseline HPV test, with 112 cases of CIN3+ diagnosed within the first year. In total, 48.6% (72/148) with HPV 16 and 57.6% (19/33) with HPV 33 developed CIN3+. Within the first year, CIN3+ was detected in 37.8% (56/148) with HPV 16, and 51.5% (17/33) with HPV 33. The long-term risk of CIN3+ was significantly lower than the short-term risk, and mainly associated with HPV 16. Overall, eight cases of cervical cancer were detected. Five were HPV positive, harboured HPV 16 at baseline and developed cervical cancer after 3, 4, 5, 11 and 24 years of follow-up. Conclusion and consequences HPV status at baseline is predictive for the subsequent risk of developing CIN3+. Women with a positive HPV test in 1990–1992 had a significantly higher risk of CIN3+ during 30 years of follow-up than those with a negative test. HPV 16 was associated with the greatest long-term risk of cervical cancer. All patients with a positive HPV test at baseline should be followed up until negative. Trial registration ISRCTN, ISRCTN10836802. Registered 14 December 2020 - Retrospectively registered.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Alex F. Martin ◽  
Sarah Denford ◽  
Nicola Love ◽  
Derren Ready ◽  
Isabel Oliver ◽  
...  

Abstract Background In December 2020, Public Health England with NHS Test and Trace initiated a pilot study in which close contacts of people with confirmed COVID-19 were given the option to carryout lateral flow device antigen tests at home, as an alternative to self-isolation for 10–14 days. In this study, we evaluated engagement with daily testing, and assessed levels of adherence to the rules relating to behaviour following positive or negative test results. Methods We conducted a service evaluation of the pilot study, examining survey responses from a subset of those who responded to an evaluation questionnaire. We used an online cross-sectional survey offered to adult contacts of confirmed COVID-19 cases who consented to daily testing. We used a comparison group of contacts who were not offered testing and instead self-isolated. Results Acceptability of daily testing was lower among survey respondents who were not offered the option of testing and among people from ethnic minority groups. Overall, 52% of respondents reported being more likely to share details of people that they had been in contact with following a positive test result, if they knew that their contacts would be offered the option of daily testing. Only 2% reported that they would be less likely to provide details of their contacts. On the days that they were trying to self-isolate, 19% of participants reported that they left the house, with no significant group differences. Following a negative test, 13% of respondents reported that they increased their contacts, but most (58%) reported having fewer risky contacts. Conclusions Our data suggest that daily testing is potentially acceptable, may facilitate sharing contact details of close contacts among those who test positive for COVID-19, and promote adherence to self-isolation. A better understanding is needed of how to make this option more acceptable for all households. The impact of receiving a negative test on behaviour remains a risk that needs to be monitored and mitigated by appropriate messaging. Future research should examine attitudes and behaviour in a context where infection levels are lower, testing is more familiar, and restrictions on activity have been reduced.


2021 ◽  
Author(s):  
Philipp Sprengholz ◽  
Luca Henkel ◽  
Cornelia Betsch

Monetary and legal incentives have been proposed to promote COVID-19 vaccination uptake. To evaluate the suitability of incentives, an experiment with German participants examined the effects of payments (varied within subjects: 0 to 10,000 EUR) and freedoms (varied between subjects: vaccination leading vs. not leading to the same benefits as a negative test result) on the vaccination intentions of previously unvaccinated individuals (n = 782). While no effect could be found for freedoms, the share of participants willing to be vaccinated increased with the payment amount. However, a significant change required large rewards of 3,250 EUR or more. While monetary incentives could increase vaccination uptake by a few percentage points, the high costs of implementation challenge the efficiency of the measure and call for alternatives. As experimental data suggest that considering vaccination as safe, necessary, and prosocial increases an individual’s likelihood of wanting to get vaccinated without payment, educational campaigns should emphasize these features when promoting vaccination against COVID-19.


BMJ Open ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. e050667
Author(s):  
Meaghan Lunney ◽  
Paul E Ronksley ◽  
Robert G Weaver ◽  
Lianne Barnieh ◽  
Norman Blue ◽  
...  

ObjectivesThis report estimates the risk of COVID-19 importation and secondary transmission associated with a modified quarantine programme in Canada.Design and participantsProspective analysis of international asymptomatic travellers entering Alberta, Canada.InterventionsAll participants were required to receive a PCR COVID-19 test on arrival. If negative, participants could leave quarantine but were required to have a second test 6 or 7 days after arrival. If the arrival test was positive, participants were required to remain in quarantine for 14 days.Main outcome measuresProportion and rate of participants testing positive for COVID-19; number of cases of secondary transmission.ResultsThe analysis included 9535 international travellers entering Alberta by air (N=8398) or land (N=1137) that voluntarily enrolled in the Alberta Border Testing Pilot Programme (a subset of all travellers); most (83.1%) were Canadian citizens. Among the 9310 participants who received at least one test, 200 (21.5 per 1000, 95% CI 18.6 to 24.6) tested positive. Sixty-nine per cent (138/200) of positive tests were detected on arrival (14.8 per 1000 travellers, 95% CI 12.5 to 17.5). 62 cases (6.7 per 1000 travellers, 95% CI 5.1 to 8.5; 31.0% of positive cases) were identified among participants that had been released from quarantine following a negative test result on arrival. Of 192 participants who developed symptoms, 51 (26.6%) tested positive after arrival. Among participants with positive tests, four (2.0%) were hospitalised for COVID-19; none required critical care or died. Contact tracing among participants who tested positive identified 200 contacts; of 88 contacts tested, 22 were cases of secondary transmission (14 from those testing positive on arrival and 8 from those testing positive thereafter). SARS-CoV-2 B.1.1.7 lineage was not detected in any of the 200 positive cases.Conclusions21.5 per 1000 international travellers tested positive for COVID-19. Most (69%) tested positive on arrival and 31% tested positive during follow-up. These findings suggest the need for ongoing vigilance in travellers testing negative on arrival and highlight the value of follow-up testing and contact tracing to monitor and limit secondary transmission where possible.


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