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Background A major goal of coronavirus disease 2019 (COVID-19) vaccination is to prevent severe outcomes (hospitalizations and deaths). We estimated the effectiveness of messenger RNA (mRNA) and ChAdOx1 COVID-19 vaccines against severe outcomes in 4 Canadian provinces between December 2020 and September 2021. Methods We conducted this multiprovincial, retrospective, test-negative study among community-dwelling adults aged ≥18 years in Ontario, Quebec, British Columbia, and Manitoba using linked provincial databases and a common study protocol. Multivariable logistic regression was used to estimate province-specific vaccine effectiveness against COVID-19 hospitalization and/or death. Estimates were pooled using random-effects models. Results We included 2 508 296 tested participants, with 31 776 COVID-19 hospitalizations and 5842 deaths. Vaccine effectiveness was 83% after a first dose and 98% after a second dose against both hospitalization and death (separately). Against severe outcomes, effectiveness was 87% (95% confidence interval [CI], 71%–94%) ≥84 days after a first dose of mRNA vaccine, increasing to 98% (95% CI, 96%–99%) ≥112 days after a second dose. Vaccine effectiveness against severe outcomes for ChAdOx1 was 88% (95% CI, 75%–94%) ≥56 days after a first dose, increasing to 97% (95% CI, 91%–99%) ≥56 days after a second dose. Lower 1-dose effectiveness was observed for adults aged ≥80 years and those with comorbidities, but effectiveness became comparable after a second dose. Two doses of vaccines provided very high protection for both homologous and heterologous schedules and against Alpha, Gamma, and Delta variants. Conclusions Two doses of mRNA or ChAdOx1 vaccine provide excellent protection against severe outcomes. [ABSTRACT FROM AUTHOR]

Background Long coronavirus disease (COVID) patients experience persistent symptoms after acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Healthcare utilization data could provide critical information on the disease burden of long COVID for service planning; however, not all patients are diagnosed or assigned long COVID diagnostic codes. We developed an algorithm to identify individuals with long COVID using population-level health administrative data from British Columbia (BC), Canada. Methods An elastic net penalized logistic regression model was developed to identify long COVID patients based on demographic characteristics, pre-existing conditions, COVID-19-related data, and all symptoms/conditions recorded >28–183 days after the COVID-19 symptom onset/reported (index) date of known long COVID patients (n = 2430) and a control group (n = 24 300), selected from all adult COVID-19 cases in BC with an index date on/before October 31, 2021 (n = 168 111). Known long COVID cases were diagnosed in a clinic and/or had the International Classification of Diseases, Tenth Revision, Canada (ICD-10-CA) code for "post COVID-19 condition" in their records. Results The algorithm retained known symptoms/conditions associated with long COVID, demonstrating high sensitivity (86%), specificity (86%), and area under the receiver operator curve (93%). It identified 25 220 (18%) long COVID patients among the remaining 141 381 adult COVID-19 cases, >10 times the number of known cases. Known and predicted long COVID patients had comparable demographic and health-related characteristics. Conclusions Our algorithm identified long COVID patients with a high level of accuracy. This large cohort of long COVID patients will serve as a platform for robust assessments on the clinical course of long COVID, and provide much needed concrete information for decision-making. [ABSTRACT FROM AUTHOR]

The surface heat flow of southern South America was examined based on an updated database containing 1113 locations. Accordingly, this study presents the most accurate heat flow map of the southern portion of the continent (south of 16°30′S latitude), covering areas that previously presented limited information. The main anomalies show a strong spatial correlation with geothermal zones and with the most up-to-date lithospheric thickness maps. The blanketing effect produced by the sedimentary basins reduce the surface heat flow up to 27 mW m–2 over the thickest basins. The study region was separated into four large areas and their connection to tectonic processes analysed. The Central Andes present high heat flow zones related to a thick radiogenic crust, volcanic activity, and a hot asthenospheric wedge. In the Pampean flat-slab region, the low heat flow coincides mostly with the horizontal projection of the Juan Fernández aseismic ridge and not with a wide region as previously thought. Furthermore, a close relationship between the subduction of the ridges at different angles and a cold upper-plate lithosphere is suggested. Besides active regions of arc magmatism and a thin lithosphere, we propose that a hot upper-plate upwelling beneath the Patagonian Platform is also contributing to the high heat flow in the area. The foreland region exhibits a low heat flow coinciding with a thick cratonic lithosphere, and local high heat flow values in suture zones possibly triggered by ancient delamination beneath these regions. [ABSTRACT FROM AUTHOR]

Antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were detected in 303/673 rural Ecuadorian adults (45%), 77% of whom had compatible clinical manifestations. Seropositivity was associated with the use of open latrines. Our findings support the fears of mass spread of SARS-CoV-2 in rural Latin America and cannot exclude a contributing role for fecal-oral transmission. [ABSTRACT FROM AUTHOR]

Background: Toxocariasis is a widespread zoonotic disease caused by the nematode Toxocara canis. In Venezuela, the magnitude of the disease is unknown and seroepidemiological studies have not been previously carried out in Aragua state. Methods: A cross-sectional field study was conducted in eight preschools in three municipalities from Aragua state in Venezuela. A total of 224 children aged between 1 and 6 years were studied (43.8% [98/224] male and 56.2% [126/224] female). Blood samples were obtained for detection of IgG antibodies against Toxocara spp. using ELISA. Participating families were given a questionnaire and children included in the study were clinically evaluated by paediatricians, and signs and symptoms observed were included in the questionnaires. Results: Anti-Toxocara spp. antibodies were detected in 29.0% (65/224) of children. The seroprevalence in the different preschools studied ranged between 4.2% and 60.6%. Leucocytosis and eosinophilia were also detected. Analysis of questionnaires indicated that boys were more at risk than girls. Younger children were also more at risk. Other significant risk factors were socio-economic strata (IV and V), inadequate improvised housing, earthen flooring indoors and outdoors and the presence of dogs in preschools. Conclusions: The results from this work show the presence of infection and a high prevalence of antibodies against Toxocara spp. in the studied municipalities and indicate that toxocariasis poses a serious health problem to preschool children in Aragua state. [ABSTRACT FROM AUTHOR]

Aims To compare the tissue coverage of a hydrophilic polymer-coated zotarolimus-eluting stent (ZES) vs. a fluoropolymer-coated everolimus-eluting stent (EES) at 13 months, using optical coherence tomography (OCT) in an ‘all-comers' population of patients, in order to clarify the mechanism of eventual differences in the biocompatibility and thrombogenicity of the devices. Methods and results Patients randomized to angiographic follow-up in the RESOLUTE All Comers trial (NCT00617084) at pre-specified OCT sites underwent OCT follow-up at 13 months. Tissue coverage and apposition were assessed strut by strut, and the results in both treatment groups were compared using multilevel logistic or linear regression, as appropriate, with clustering at three different levels: patient, lesion, and stent. Fifty-eight patients (30 ZES and 28 EES), 72 lesions, 107 stents, and 23 197 struts were analysed. Eight hundred and eighty-seven and 654 uncovered struts (7.4 and 5.8%, P= 0.378), and 216 and 161 malapposed struts (1.8 and 1.4%, P= 0.569) were found in the ZES and EES groups, respectively. The mean thickness of coverage was 116 ± 99 µm in ZES and 142 ± 113 µm in EES (P= 0.466). No differences in per cent neointimal volume obstruction (12.5 ± 7.9 vs. 15.0 ± 10.7%) or other areas–volumetric parameters were found between ZES and EES, respectively. Conclusion No significant differences in tissue coverage, malapposition, or lumen/stent areas and volumes were detected by OCT between the hydrophilic polymer-coated ZES and the fluoropolymer-coated EES at 13-month follow-up. [ABSTRACT FROM PUBLISHER]

Aims To compare the global characteristics of patients with and without evidence of plaque rupture (PR) in their coronary tree and to evaluate the phenotype of ruptured plaques using intravascular ultrasound (IVUS) radiofrequency data analysis (IVUS-VH). [ABSTRACT FROM PUBLISHER]