scholarly journals Performance of self-collected anterior nasal swabs and saliva specimens for detection of SARS-COV-2 during symptomatic and asymptomatic periods

2021 ◽  
Author(s):  
Carlos G Grijalva ◽  
Melissa Rolfes ◽  
Yuwei Zhu ◽  
James Chappell ◽  
Natasha Halasa ◽  
...  
Keyword(s):  
Field Studies ◽  
Kappa Statistics ◽  
Non Invasive ◽  
Specimen Type ◽  
Household Transmission ◽  
Specimen Collection ◽  
Nasal Swabs ◽  
Transmission Study ◽  
The Difference ◽  
Study Participants

Abstract Background Anterior nasal swabs (ANS) are established specimen collection methods for SARS-CoV-2 infection detection. While saliva (SA) specimens provide an alternative, few studies have comprehensively characterized the performance of SA specimens in longitudinal studies. Methods We compared SARS-CoV-2 detections between paired self-collected ANS and SA specimens from a household transmission study. Participants recorded symptoms and paired ANS and SA specimens daily for 14 days. Specimens were tested using RT-PCR. We calculated the proportion of detections identified by each specimen type among the detections from both types combined. We computed percent agreement and Kappa statistics to assess concordance in detections. We also computed estimates stratified by presence of symptoms, and examined the influence of traditional and inactivating transport media on the performance of ANS. Results We examined 2535 self-collected paired specimens from 216 participants. Among 1,238(49%) paired specimens with detections by either specimen type, ANS identified 77.1%[954](95%CI: 74.6–79.3%) and SA 81.9%[1014](79.7–84.0%), with a difference of 4.9%(1.4–8.5%). Overall agreement was 80.0% and Kappa was 0.6(0.5-0.6). Nevertheless, the difference in the proportion of detections identified by ANS and SA using traditional and inactivating transport media was 32.5%(26.8–38.0) and −9.5%(−13.7– -5.2), respectively. Among participants who remained asymptomatic, the difference in detections between SA and ANS was 51.2%(31.8–66.0) and 26.1%(0–48.5) using traditional and inactivating media, respectively. Conclusion Self-collected saliva specimens provide a non-invasive alternative to nasal swabs, especially to those collected in traditional transport media, for longitudinal field studies that aim to detect both symptomatic and asymptomatic SARS-CoV-2 infections.

Absenteeism and presenteeism in healthcare workers due to respiratory illness

2020 ◽  
pp. 1-6
Author(s):  
Stefan P. Kuster ◽  
Jürg Böni ◽  
Roger D. Kouyos ◽  
Michael Huber ◽  
Stefan Schmutz ◽  
...  
Keyword(s):  
Healthcare Workers ◽  
Respiratory Symptoms ◽  
Influenza Infection ◽  
Respiratory Illness ◽  
Daily Basis ◽  
Nasal Swabs ◽  
Transmission Study ◽  
Working Day ◽  
Study Participants ◽  
Acute Healthcare

Abstract Objective: To assess influenza symptoms, adherence to mask use recommendations, absenteesm and presenteeism in acute care healthcare workers (HCWs) during influenza epidemics. Methods: The TransFLUas influenza transmission study in acute healthcare prospectively followed HCWs prospectively over 2 consecutive influenza seasons. Symptom diaries asking for respiratory symptoms and adherence with mask use recommendations were recorded on a daily basis, and study participants provided midturbinate nasal swabs for influenza testing. Results: In total, 152 HCWs (65.8% nurses and 13.2% physicians) were included: 89.1% of study participants reported at least 1 influenza symptom during their study season and 77.8% suffered from respiratory symptoms. Also, 28.3% of HCW missed at least 1 working day during the study period: 82.6% of these days were missed because of symptoms of influenza illness. Of all participating HCWs, 67.9% worked with symptoms of influenza infection on 8.8% of study days. On 0.3% of study days, symptomatic HCWs were shedding influenza virus while at work. Among HCWs with respiratory symptoms, 74.1% adhered to the policy to wear a mask at work on 59.1% of days with respiratory symptoms. Conclusions: Respiratory disease is frequent among HCWs and imposes a significant economic burden on hospitals due to the number of working days lost. Presenteesm with respiratory illness, including influenza, is also frequent and poses a risk for patients and staff. Trial registration: NCT02478905 (clinicaltrials.gov)

scholarly journals High secondary attack rate and persistence of SARS-CoV-2 antibodies in household transmission study participants, Finland 2020

2021 ◽  
Author(s):  
Timothee Dub ◽  
Hanna Nohynek ◽  
Lotta Hagberg ◽  
Oona Liedes ◽  
Anu Haveri ◽  
...  
Keyword(s):  
Attack Rate ◽  
Neutralizing Antibodies ◽  
Serum Samples ◽  
Household Transmission ◽  
Transmission Study ◽  
Household Members ◽  
Transmission Studies ◽  
Study Participants ◽  
Index Cases

Background Household transmission studies offer the opportunity to assess both secondary attack rate and persistence of SARS-CoV-2 antibodies over time. Methods We invited confirmed COVID-19 cases and their household members to attend up to four household visits with collection of nasopharyngeal and serum samples over 28 days after index case onset. We calculated secondary attack rates (SAR) based on the presence of SARS-CoV-2 nucleoprotein IgG antibodies (IgG Ab) and/or neutralizing antibodies (NAb) overall and per households. Three and six months later, we assessed the persistence of SARS-CoV-2 antibodies. Findings We recruited 39 index cases and 90 household members. Among 87 household members evaluated, SAR was 48% (n=42), including 37 symptomatic secondary cases. In total, 80/129 (62%) participants developed both IgG Ab and NAb, while three participants only developed IgG Ab. Among participants who had both IgG Ab and NAb during the initial follow-up, 68/69 (99%) and 63/70 (90%) had IgG Ab and NAb at 3 months, while at 6 months, 59/75 (79%) and 63/75 (84%) had IgG Ab and NAb, respectively. Participants who required hospital care had initially 5-fold IgG Ab concentrations compared to cases with mild symptoms and 8-fold compared to asymptomatic cases. Interpretation Following detection of a COVID-19 case in a household, other members had a high risk of becoming infected. Follow-up of participants showed strong persistence of antibodies in most cases. Funding This study was supported by THL coordinated funding for COVID-19 research (Finnish Government's supplementary budget) and by the Academy of Finland (Decision number 336431).

scholarly journals Performance of Unobserved Self-Collected Nasal Swabs for Detection of SARS-CoV-2 by RT-PCR Utilizing a Remote Specimen Collection Strategy

2021 ◽  
Author(s):  
Ron M Kagan ◽  
Amy A Rogers ◽  
Gwynngelle A Borillo ◽  
Nigel J Clarke ◽  
Elizabeth M Marlowe
Keyword(s):  
Return To Work ◽  
Screening Program ◽  
False Negative ◽  
N Gene ◽  
Rt Pcr ◽  
Pooled Testing ◽  
Specimen Collection ◽  
Asymptomatic Patients ◽  
Nasal Swabs ◽  
The Impact

Abstract Background The use of a remote specimen collection strategy employing a kit designed for unobserved self-collection for SARS-CoV-2 RT-PCR can decrease the use of PPE and exposure risk. To assess the impact of unobserved specimen self-collection on test performance, we examined results from a SARS-CoV-2 qualitative RT-PCR test for self-collected specimens from participants in a return-to-work screening program and assessed the impact of a pooled testing strategy in this cohort. Methods Self-collected anterior nasal swabs from employee return to work programs were tested using the Quest Diagnostics SARS-CoV-2 RT-PCR EUA. The Ct values for the N1 and N3 N-gene targets and a human RNase P (RP) gene control target were tabulated. For comparison, we utilized Ct values from a cohort of HCP-collected specimens from patients with and without COVID-19 symptoms. Results Among 47,923 participants, 1.8% were positive. RP failed to amplify for 13/115,435 (0.011%) specimens. The median (IQR) Cts were 32.7 (25.0-35.7) for N1 and 31.3 (23.8-34.2) for N3. Median Ct values in the self-collected cohort were significantly higher than those of symptomatic, but not asymptomatic patients. Based on Ct values, pooled testing with 4 specimens would have yielded inconclusive results in 67/1,268 (5.2%) specimens but only a single false-negative result. Conclusions Unobserved self-collection of nasal swabs provides adequate sampling for SARS-CoV-2 RT-PCR testing. These findings alleviate concerns of increased false negatives in this context. Specimen pooling could be used for this population as the likelihood of false negative results is very low due when using a sensitive, dual-target methodology.

Point-of-Care Testing Using Invasive and Non-Invasive Hemoglobinometers: Reliable and Valid Method for Estimation of Hemoglobin among Children 6–59 Months

2020 ◽  
Author(s):  
Gomathi Ramaswamy ◽  
Kashish Vohra ◽  
Kapil Yadav ◽  
Ravneet Kaur ◽  
Tripti Rai ◽  
...  
Keyword(s):  
Point Of Care ◽  
Venous Blood ◽  
Public Health Problem ◽  
Outpatient Department ◽  
Point Of Care Testing ◽  
Adequate Treatment ◽  
Non Invasive ◽  
Hematology Analyzer ◽  
The Mean ◽  
Study Participants

Abstract Introduction Globally around 47.4% of children and in India, 58% of children aged 6–59 months are anemic. Diagnosis of anemia in children using accurate technologies and providing adequate treatment is essential to reduce the burden of anemia. Point-of-care testing (POCT) devices is a potential option for estimation of hemoglobin in peripheral and field settings were the hematology analyzer and laboratory services are not available. Objectives To access the validity of the POCTs (invasive and non-invasive devices) for estimation of hemoglobin among children aged 6–59 months compared with hematology analyzer. Methods The study participants were enrolled from the pediatric outpatient department in Haryana, India, from November 2019 to January 2020. Hemoglobin levels of the study participants were estimated in Sahli’s hemoglobinometer and invasive digital hemoglobinometers (DHs) using capillary blood samples. Hemoglobin levels in non-invasive DH were assessed from the finger/toe of the children. Hemoglobin levels measured in POCTs were compared against the venous blood hemoglobin estimated in the hematology analyzer. Results A total of 120 children were enrolled. The mean (SD) of hemoglobin (g/dl) estimated in auto-analyzer was 9.4 (1.8), Sahli’s hemoglobinometer was 9.2 (1.9), invasive DH was 9.7 (1.9), and non-invasive DH was 11.9 (1.5). Sahli’s hemoglobinometer (95.5%) and invasive DH (92.2%) had high sensitivity for the diagnosis of anemia compared with non-invasive DH (24.4%). In contrast, non-invasive DH had higher specificity (96.7%) compared with invasive DH (83.3%) and Sahli’s hemoglobinometer (70%). Invasive DH took the least time (2–3 min) for estimation of hemoglobin per participant, followed by Sahli’s (4–5 min) and non-invasive DH (5–7 min). Conclusion All three POCT devices used in this study are reasonable and feasible for estimating hemoglobin in under-5 children. Invasive DHs are potential POCT devices for diagnosis of anemia among under-5 children, while Sahli’s can be considered as a possible option, where trained and skilled technicians are available. Further research and development are required in non-invasive DH to improve accuracy. Lay summary In India, anemia is a serious public health problem, where 58% of the children aged 6–59 months are anemic. Point-of-care testing (POCT) using digital hemoglobinometers (DHs) has been recommended as one of the key interventions by the Anemia Mukt Bharat program since 2018 in India. These POCT devices are easy to use, less invasive, can be carried to field, require minimal training and results are available immediately. Therefore this study assessed the validity of POCT devices—invasive DH, non-invasive DH and Sahli’s hemoglobinometer among 6–59 months children in facility setting compared with the gold standard hematology analyzer. A total of 120 children under 6–59 months of age were enrolled from the pediatric outpatient department in Haryana, India, from November 2019 to January 2020. The (mean hemoglobin in g/dl) invasive (9.7) and non-invasive DH (11.9) overestimated hemoglobin value, while Sahli’s (9.2) underestimated hemoglobin compared with hematology analyzer (9.4). Invasive DH (92.2%) and Sahli’s hemoglobinometer (95.5%) reported high ability to correctly identify those with anemia compared with non-invasive DH (24.4%). In contrast, non-invasive DH (96.73%) had higher ability to correctly identify those without the anemia compared with invasive DH (83.3%) and Sahli’s (70%).

Weed Control with Reduced Rates of Chlorimuron Plus Metribuzin and Imazethapyr in No-Till Narrow-Row Soybean (Glycine max)

1998 ◽  
Vol 12 (1) ◽  
pp. 32-36 ◽  
Author(s):  
William G. Johnson ◽  
Jeffrey S. Dilbeck ◽  
Michael S. Defelice ◽  
J. Andrew Kendig
Keyword(s):  
Glycine Max ◽  
Weed Control ◽  
Field Studies ◽  
Weed Suppression ◽  
Crop Response ◽  
Soybean Production ◽  
No Till ◽  
Giant Foxtail ◽  
The Difference ◽  
Narrow Row

Field studies were conducted at three locations in 1993 and 1994 to evaluate weed control and crop response to combinations of glyphosate, metolachlor, 0.5 X and 1 X label rates of chlorimuron plus metribuzin applied prior to planting (PP), and 0.5 X and 1 X label rates of imazethapyr applied early postemergence (EPOST) or postemergence (POST) in no-till narrow-row soybean production. Giant foxtail densities were reduced with sequential PP followed by (fb) EPOST or POST treatments. Large crabgrass was reduced equivalently with all herbicide combinations involving chlorimuron plus metribuzin PP fb imazethapyr. Common cocklebur control was variable but was usually greater with treatments that included imazethapyr. Ivyleaf morningglory densities were not reduced with any herbicide combinations. Sequential PP fb EPOST or POST treatments tended to provide slightly better weed suppression than PP-only treatments, but the difference was rarely significant. Soybean yields with treatments utilizing 0.5 X rates were usually equal to 1 X rates.

The difference in miR-21 expression levels between invasive and non-invasive breast cancers emphasizes its role in breast cancer invasion

2014 ◽  
Vol 31 (3) ◽  
Author(s):  
Nina Petrović ◽  
Vesna Mandušić ◽  
Boban Stanojević ◽  
Silvana Lukić ◽  
Lidija Todorović ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Invasion ◽  
Breast Cancers ◽  
Expression Levels ◽  
Non Invasive ◽  
Breast Cancer Invasion ◽  
The Difference

scholarly journals Reconstruction of input functions from a dynamic PET image with sequential administration of 15O2 and H215O for noninvasive and ultra-rapid measurement of CBF, OEF, and CMRO2

2017 ◽  
Vol 38 (5) ◽  
pp. 780-792 ◽  
Author(s):  
Nobuyuki Kudomi ◽  
Yukito Maeda ◽  
Hiroyuki Yamamoto ◽  
Yuka Yamamoto ◽  
Tetsuhiro Hatakeyama ◽  
...  
Keyword(s):  
Rate Constants ◽  
Human Subjects ◽  
Invasive Procedure ◽  
Invasive Technique ◽  
Invasive Approach ◽  
Non Invasive ◽  
Sequential Administration ◽  
Invasive Method ◽  
The Difference ◽  
Arterial Input Functions

CBF, OEF, and CMRO2 images can be quantitatively assessed using PET. Their image calculation requires arterial input functions, which require invasive procedure. The aim of the present study was to develop a non-invasive approach with image-derived input functions (IDIFs) using an image from an ultra-rapid O2 and C15O2 protocol. Our technique consists of using a formula to express the input using tissue curve with rate constants. For multiple tissue curves, the rate constants were estimated so as to minimize the differences of the inputs using the multiple tissue curves. The estimated rates were used to express the inputs and the mean of the estimated inputs was used as an IDIF. The method was tested in human subjects ( n = 24). The estimated IDIFs were well-reproduced against the measured ones. The difference in the calculated CBF, OEF, and CMRO2 values by the two methods was small (<10%) against the invasive method, and the values showed tight correlations ( r = 0.97). The simulation showed errors associated with the assumed parameters were less than ∼10%. Our results demonstrate that IDIFs can be reconstructed from tissue curves, suggesting the possibility of using a non-invasive technique to assess CBF, OEF, and CMRO2.

scholarly journals A potential new fabric evaluation approach by capturing brain perception under fabric contact pressure

2018 ◽  
Vol 89 (16) ◽  
pp. 3312-3325 ◽  
Author(s):  
Jie Yuan ◽  
Weidong Yu ◽  
Kemin Chen ◽  
Zhongwei Zhang ◽  
Yi Li ◽  
...  
Keyword(s):  
Contact Pressure ◽  
Inhibitory Effect ◽  
High Temporal Resolution ◽  
Non Invasive ◽  
Evaluation Approach ◽  
Postcentral Gyrus ◽  
Comfort Perception ◽  
Peak Points ◽  
The Difference ◽  
Fabric Comfort

The problem of the transmission mechanism of textile perception and the barrier to express textile cognition directly are the two major issues in the field of textile evaluation. In this study, an advanced biomedical imaging technology, functional magnetic resonance imaging, which is non-invasive and has a high temporal resolution and spatial resolution, was utilized to describe the features of brain perception in the brain mask areas under increased fabric contact pressures, and thus it was attempted to provide a new approach to express fabric comfort perception. As a result, we found that when fabric contact pressure increased from 0.5 to 1.5 kPa, both maximum activation intensity T Z and activation proportion K of the peak points were transferred from the postcentral gyrus in the SI to the amygdala, and were negative activations. Therefore, we drew the conclusion that both a lower and a higher fabric contact pressure (about 1 kPa of proper comfort fabric pressure) would produce a brain signal inhibitory effect on the SI and amygdala. The difference was the fact that the inhibition role on the SI was more obvious under a lower pressure, while the inhibition role on the amygdala was more remarkable under a higher pressure, which meant that the SI, particularly the postcentral gyrus in the SI, was likely to play a significant role in surface tactile perception of fabrics, while the amygdala might be related to the fabric oppressing sensation.

scholarly journals Does a Comparison View Improve the Reliability of Staging Wrist Osteoarthritis?

Hand ◽  
2016 ◽  
Vol 12 (5) ◽  
pp. 439-445 ◽  
Author(s):  
Paul W. L. ten Berg ◽  
Tessa Drijkoningen ◽  
Thierry G. Guitton ◽  
David Ring
Keyword(s):  
Survey Study ◽  
Kappa Statistics ◽  
Scaphoid Nonunion ◽  
Educational Training ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Significant Difference ◽  
The Difference ◽  
Improve Reliability ◽  
Comparison View

Background: Radiological grading of wrist osteoarthritis associated with scaphoid nonunion advanced collapse (SNAC) can be difficult. A comparison radiograph of the contralateral healthy wrist and an educational training in the various SNAC stages may improve reliability. Our purposes were to evaluate the difference in the reliability: (1) between observers who rate SNAC wrists with and without a comparison radiograph; and (2) between observers who receive training prior to ratings and those who do not. Methods: In this cross-sectional survey study, 82 fully trained orthopedic or hand surgeons rated anteroposterior radiographs of 19 patient wrists following a scaphoid nonunion based on SNAC stages 0 to 4. Observers were randomized online in 4 groups: one group rated unilateral views without training, a second group unilateral views with training, a third group bilateral views without training, and a fourth group bilateral views with training. Training included a 1-page clarification of the SNAC stages. Interobserver agreement was calculated using kappa statistics. Results: There was no significant difference between agreement between observers who rated unilateral radiographs (κ = 0.55) and who rated bilateral radiographs (κ = 0.58) ( P = .14), nor between agreement between observers who received training (κ = 0.59) and who did not (κ = 0.54) ( P = .058). Conclusions: The use of an additional comparison view and/or training does not seem to be clinically relevant in SNAC staging. There is room for improvement in the way we assess patients with SNAC wrists.

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