scholarly journals Defining the role of asymptomatic and pre-symptomatic SARS-CoV-2 transmission – a living systematic review

Author(s):  
Xueting Qiu ◽  
Ali Ihsan Nergiz ◽  
Alberto Enrico Maraolo ◽  
Isaac I. Bogoch ◽  
Nicola Low ◽  
...  

AbstractBackgroundReports suggest that asymptomatic individuals (those with no symptoms at all throughout the infection) with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are infectious, but the extent of asymptomatic transmission requires further understanding.PurposeThis living review aims to critically appraise available data about secondary attack rates from people with asymptomatic and pre-symptomatic SARS-CoV-2 infection.Data sourcesMedline, EMBASE, China Academic Journals full-text database (CNKI), and pre-print servers were searched from 30 December 2019 to 3 July 2020 using relevant MESH terms.Study selectionStudies that report on contact tracing of index cases with asymptomatic or pre-symptomatic SARS-CoV-2 infection, in either English or Chinese were included.Data extractionTwo authors independently extracted data and assessed study quality and risk of bias. We calculated the secondary attack rate as the number of contacts with SARS-CoV-2, divided by the number of contacts tested.Data synthesisOf 928 studies identified, 19 were included. Secondary attack rates from asymptomatic index cases ranged from 0% to 2.8% (9 studies). Pre-symptomatic secondary attack rates ranged from 0.7% to 31.8% (10 studies). The highest secondary attack rates were found in contacts who lived in the same household as the index case. Other activities associated with transmission were group activities such as sharing meals or playing board games with the index case.LimitationsWe excluded some studies because the index case or number of contacts were unclear. Owing to the anticipated heterogeneity, we did not produce a summary estimate of the included studies.ConclusionAsymptomatic patients can transmit SARS-CoV-2 to others, but our findings indicate that such individuals are responsible for fewer secondary infections than people with symptoms in the same studies.Systematic review registrationPROSPERO CRD42020188168

CJEM ◽  
2014 ◽  
Vol 16 (01) ◽  
pp. 69-79 ◽  
Author(s):  
Robert Green ◽  
Brian Hutton ◽  
Jason Lorette ◽  
Dominique Bleskie ◽  
Lauralyn Mclntyre ◽  
...  

ABSTRACTObjective:Hemodynamic instability following emergent endotracheal intubation (EETI) is a potentially life-threatening adverse event. The objectives of this systematic literature review were to document the incidence of postintubation hemodynamic instability (PIHI), to determine the definitions for PIHI used in the available literature, and to examine factors associated with PIHI in adult patients who require EETI.Data Source:Articles published in Medline (1966–August 2012).Study Selection:This systematic review included adult, inhospital studies of EETIs. Studies with nonemergent or pediatric patient populations were excluded.Data Extraction:Two authors independently performed data abstraction. Disagreements were resolved by a third party. The methodological quality of included studies was assessed with the Newcastle-Ottawa Quality Assessment Scale for Cohort Studies.Data Synthesis:We estimated the pooled prevalence of PIHI across studies using a random effects meta-analysis. Subgroups analyzed included study design, intubation setting, geographic location of the study, physician experience, medications used for sedation, neuromuscular blockade, and definition of PIHI. Eighteen studies were analyzed, with sample sizes from 84 to 2,833 patients. The incidence of PIHI ranged from 5 to 440 cases per 1,000 intubations, with a pooled estimate of 110 cases per 1,000 intubations (95% CI 65–167).Conclusions:PIHI was found to occur in 110 cases per 1,000 in-hospital, emergent intubations. However, heterogeneity among the included studies limits the reliability of this summary estimate. Further investigation is warranted.


2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Abdou Fatawou Modiyinji ◽  
Jean Joel Bigna ◽  
Sebastien Kenmoe ◽  
Fredy Brice N. Simo ◽  
Marie A. Amougou ◽  
...  

Abstract Background Hepatitis E virus (HEV) is a major cause of acute hepatitis in humans worldwide and have high burden in the resource-limited countries. Better knowledge of the epidemiology of hepatitis in animals in Africa can help to understand the epidemiology among humans. The objective of this study was to summarize the prevalence of HEV infection and distribution of HEV genotypes among animals in Africa. Methods In this systematic review and meta-analysis, we comprehensively searched PubMed, EMBASE, African Journals Online, and Africa Index Medicus from January 1st, 2000 to March 22th, 2020 without any language restriction. We considered cross-sectional studies of HEV infection in animals in Africa. Study selection, data extraction, and methodological quality of included studies were done independently by two investigators. Prevalence data were pooled using the random-effects meta-analysis. This review was registered in PROSPERO, CRD42018087684. Results Twenty-five studies (13 species and 6983 animals) were included. The prevalence (antibodies or ribonucleic acid [RNA]) of HEV infection in animals varied widely depending on biological markers of HEV infection measured: 23.4% (95% confidence interval; 12.0–37.2) for anti-HEV immunoglobulins G, 13.1% (3.1–28.3) for anti-HEV immunoglobulins M, and 1.8% (0.2–4.3) for RNA; with substantial heterogeneity. In subgroup analysis, the immunoglobulins G seroprevalence was higher among pigs 37.8% (13.9–65.4). The following HEV genotypes were reported in animals: Rat-HEV genotype 1 (rats and horses), HEV-3 (pigs), HEV-7 (dromedaries), and Bat hepeviruses (bats). Conclusions We found a high prevalence of HEV infection in animals in Africa and HEV genotypes close to that of humans. Some animals in Africa could be the reservoir of HEV, highlighting the need of molecular epidemiological studies for investigating zoonotic transmission.


2020 ◽  
Vol 9 (4) ◽  
pp. e000843
Author(s):  
Kelly Bos ◽  
Maarten J van der Laan ◽  
Dave A Dongelmans

PurposeThe purpose of this systematic review was to identify an appropriate method—a user-friendly and validated method—that prioritises recommendations following analyses of adverse events (AEs) based on objective features.Data sourcesThe electronic databases PubMed/MEDLINE, Embase (Ovid), Cochrane Library, PsycINFO (Ovid) and ERIC (Ovid) were searched.Study selectionStudies were considered eligible when reporting on methods to prioritise recommendations.Data extractionTwo teams of reviewers performed the data extraction which was defined prior to this phase.Results of data synthesisEleven methods were identified that are designed to prioritise recommendations. After completing the data extraction, none of the methods met all the predefined criteria. Nine methods were considered user-friendly. One study validated the developed method. Five methods prioritised recommendations based on objective features, not affected by personal opinion or knowledge and expected to be reproducible by different users.ConclusionThere are several methods available to prioritise recommendations following analyses of AEs. All these methods can be used to discuss and select recommendations for implementation. None of the methods is a user-friendly and validated method that prioritises recommendations based on objective features. Although there are possibilities to further improve their features, the ‘Typology of safety functions’ by de Dianous and Fiévez, and the ‘Hierarchy of hazard controls’ by McCaughan have the most potential to select high-quality recommendations as they have only a few clearly defined categories in a well-arranged ordinal sequence.


Author(s):  
Hayley A Thompson ◽  
Andria Mousa ◽  
Amy Dighe ◽  
Han Fu ◽  
Alberto Arnedo-Pena ◽  
...  

Abstract Background Understanding the drivers of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission is crucial for control policies, but evidence of transmission rates in different settings remains limited. Methods We conducted a systematic review to estimate secondary attack rates (SARs) and observed reproduction numbers (Robs) in different settings exploring differences by age, symptom status, and duration of exposure. To account for additional study heterogeneity, we employed a beta-binomial model to pool SARs across studies and a negative-binomial model to estimate Robs. Results Households showed the highest transmission rates, with a pooled SAR of 21.1% (95% confidence interval [CI]:17.4–24.8). SARs were significantly higher where the duration of household exposure exceeded 5 days compared with exposure of ≤5 days. SARs related to contacts at social events with family and friends were higher than those for low-risk casual contacts (5.9% vs 1.2%). Estimates of SARs and Robs for asymptomatic index cases were approximately one-seventh, and for presymptomatic two-thirds of those for symptomatic index cases. We found some evidence for reduced transmission potential both from and to individuals younger than 20 years of age in the household context, which is more limited when examining all settings. Conclusions Our results suggest that exposure in settings with familiar contacts increases SARS-CoV-2 transmission potential. Additionally, the differences observed in transmissibility by index case symptom status and duration of exposure have important implications for control strategies, such as contact tracing, testing, and rapid isolation of cases. There were limited data to explore transmission patterns in workplaces, schools, and care homes, highlighting the need for further research in such settings.


2018 ◽  
Vol 28 (5) ◽  
pp. 566-573 ◽  
Author(s):  
Thierry Gagné ◽  
Joseph G L Lee ◽  
Madeleine Steinmetz-Wood ◽  
Katherine L Frohlich

ObjectiveSocioeconomic circumstances are critically important to addressing smoking. In young adulthood (ages 18–25), dynamic transitions in education, employment, family and housing complicate the measurement of socioeconomic circumstances. To better understand approaches to capturing these circumstances, this methodological systematic review examined how socioeconomic characteristics used to identify social inequalities in smoking among young adults are measured.Data sourcesWe searched PubMed/MEDLINE, Scopus, EMBASE, ERIC and Sociological Abstracts, and used three prior reviews. We updated the search in March 2018.Study selectionTwo reviewers independently screened peer-reviewed records from OECD countries published in English, French, German or Spanish after 1995 whose samples covered at least 1 year between the ages of 18 and 25. We included 89 of 1320 records.Data extractionOne reviewer extracted study characteristics, indicators used to operationalise socioeconomic circumstances and each indicator’s relation to results on smoking (ie, significance and direction). We found 39 indicators of socioeconomic circumstances related to six broad domains. These indicators were used in 425 results.Data synthesisWe descriptively analysed the extracted data using evidence tables. Educational attainment was most common. Evidence of inequalities varied by indicator used. For example, there was inconsistent evidence regarding the role of parental characteristics and transition stages and insufficient evidence regarding personal income on smoking.ConclusionDespite its importance, studies have disproportionally examined inequalities among young adults using traditional indicators. The mismatch between young adults’ life transitions and measurement strategies may attenuate evidence of inequalities. We suggest strategies to improve future measurement.


Medicina ◽  
2021 ◽  
Vol 58 (1) ◽  
pp. 1
Author(s):  
Hye Won Lee ◽  
Lin Ang ◽  
Jung Tae Kim ◽  
Myeong Soo Lee

Background and Objectives: This review aimed to provide an updated review of evidence regarding the effects of aromatherapy in relieving symptoms of burn injuries, focusing on pain and physiological distress. Materials and Methods: Fifteen databases (including five English databases, four Korean medical databases, and four Iranian databases) and trial registries were searched for studies published between their dates of inception and July 2021. Two review authors individually performed study selection, data extraction, and risk of bias assessment, and any discrepancies were solved by a third review author. Results: Eight RCTs met our inclusion criteria and were analyzed in this updated systematic review. Our meta-analyses revealed that inhaled aromatherapy plus routine care showed beneficial effects in relieving pain after dressing, as compared to placebo plus routine care (p < 0.00001) and routine care alone (p = 0.02). Additionally, inhaled aromatherapy plus routine care (p < 0.00001) and aromatherapy massage plus routine care (p < 0.0001) also showed superior effects in calming anxiety, as compared to routine care alone. None of the included studies reported on AEs. Overall, the risk of bias across the studies was concerning. Conclusions: This updated review and synthesis of the studies had brought a more detailed understanding of the potential application of aromatherapy for easing the pain and anxiety of burn patients.


Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 533
Author(s):  
Riccardo Nucera ◽  
Carolina Dolci ◽  
Angela Mirea Bellocchio ◽  
Stefania Costa ◽  
Serena Barbera ◽  
...  

This systematic review aims to highlight the differences between different clear aligner therapies that differ in the presence of attachments or in attachment configuration. Eight electronic databases were searched up to March 2020. Two authors independently proceeded to study selection, data extraction, and risk of bias assessment. The analysis of the results was carried out examining six groups of movements (mesio-distal tipping/bodily movement; anterior bucco-lingual tipping/root torque; posterior bucco-lingual tipping/expansion; intrusion; extrusion; rotation). Five clinical trials were selected and all of them showed a medium risk of bias. Literature showed that attachments mostly increase the effectiveness of orthodontic treatment with clear aligners, improving anterior root torque, rotation, and mesio-distal (M-D) movement; they are also important to increase posterior anchorage. However, some articles showed contradictory or not statistically significant results. Attachments also seem to improve intrusion, but the evidence about this movement, as well as extrusion, is lacking. No studies evaluated posterior bucco-lingual tipping/expansion. Further clinical trials are strongly suggested to clarify the influence of attachments and their number, size, shape, and position on each orthodontic movement.


2021 ◽  
Author(s):  
Chiara Martinoli ◽  
Carlo La Vecchia ◽  
Sara Raimondi ◽  
Federica Bellerba ◽  
Clementina Sasso ◽  
...  

Background. The contribution of children to viral spread in schools is still under debate. We conducted a systematic review and meta-analysis of studies to investigate SARS-CoV-2 transmission in the school setting. Methods: Literature searches from April, 2021 and repeated on May, 15th 2021 yielded a total of 1088 publications: screening, contact tracing and seroprevalence studies. MOOSE guidelines were followed and data analyzed using random-effects models. Results: From screening studies involving more than 120,000 subjects, we estimated 0.31% (95% Confidence Interval [CI] 0.05-0.81%) SARS-CoV-2 point prevalence in schools. Contact tracing studies, involving a total of 112,622 contacts of children and adults, showed that onward viral transmission was limited (2.54%; 95%CI 0.76-5.31). Young index cases were found to be 74% significantly less likely than adults to favor viral spread (Odds Ratio [OR]=0.26; 95%CI 0.11-0.63) and were less susceptible to infection (OR=0.60; 95% CI 0.25-1.47). Finally, from seroprevalence studies, with a total of 17,879 subjects involved, we estimated that children are 43% significantly less likely than adults to test positive for antibodies (OR=0.57; 95%CI: 0.49-0.68). In conclusion, testing all subjects in schools, independently of symptoms, students less likely than adults favor viral spread and SARS-CoV-2 circulation in schools was found to be limited.


2020 ◽  
Author(s):  
Farzaneh Mardali ◽  
Somaye Fatahi ◽  
Maryam Alinaghizadeh ◽  
Hamed Kord Varkaneh ◽  
Mohammad Hassan Sohouli ◽  
...  

Abstract Context Some evidence has shown an association between maternal vitamin B12 levels and the development of preeclampsia in pregnant women, but the relationship between preeclampsia and vitamin B12 is not clear. Objective The aim of this systematic review was to compare serum vitamin B12 levels in women with preeclampsia with those in normotensive pregnant women. Data Sources The PubMed/MEDLINE, Scopus, and Web of Science databases were searched up to August 2019, along with the reference lists of included articles. Study Selection The literature was searched for observational studies that investigated vitamin B12 levels in women with preeclampsia. Data Extraction Data were extracted independently by 2 authors. Data were pooled using a random-effects model. Results Vitamin B12 levels in women with preeclampsia were significantly lower than those in healthy women (mean, −15.24 pg/mL; 95%CI, −27.52 to −2.954; P &lt; 0.015), but heterogeneity between studies was high (I2 = 97.8%; P = 0.0103). Subgroup analyses based on folic acid supplementation, homocysteine concentrations, and gestational age at the time of sampling for vitamin B12 assessment did not identify the sources of heterogeneity. Conclusions Women with preeclampsia had significantly lower vitamin B12 concentrations than normotensive pregnant women.


Healthcare ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 329
Author(s):  
André Hajek ◽  
Benedikt Kretzler ◽  
Hans-Helmut König

Background: Thus far, there is a lack of a systematic review synthesizing empirical studies that analyze the link between personality factors and healthcare use (HCU) or costs. Consequently, the purpose of our systematic review is to give an overview of empirical findings from observational studies examining the association between personality factors and HCU or costs. Methods: PubMed, PsycINFO, and NHS EED (NHS Economic Evaluation Database) were searched. Observational studies examining the association between personality factors and HCU costs by using validated tools were included. Two reviewers performed study selection and data extraction and evaluated the study quality. Findings were synthesized qualitatively. Results: In total, n = 15 studies (HCU, n = 14; cost studies, n = 1) were included in the final synthesis. A few studies point to an association between conscientiousness and HCU (with mixed evidence). Some more evidence was found for an association between higher agreeableness, higher extraversion, and higher openness to experience and increased HCU. The majority of studies analyzed found a link between higher neuroticism and increased HCU. Conclusion: Personality factors, and particularly neuroticism, are associated with HCU. This knowledge is important to manage healthcare use. However, future research based on longitudinal data and studies investigating the link between personality characteristics and costs are required.


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