Detection of the new SARS-CoV-2 variants of concern B.1.1.7 and B.1.351 in five SARS-CoV-2 rapid antigen tests (RATs), Germany,March 2021

SARS-CoV-2 variants of concern (VOC) should not escape molecular surveillance. We investigated if SARS-CoV-2 rapid antigen tests (RATs) could detect B.1.1.7 and B.1.351 VOCs in certain laboratory conditions. Infectious cell culture supernatants containing B.1.1.7, B.1.351 or non-VOC SARS-CoV-2 were respectively diluted both in DMEM and saliva. Dilutions were analysed with Roche, Siemens, Abbott, nal von minden and RapiGEN RATs. While further studies with appropriate real-life clinical samples are warranted, all RATs detected B.1.1.7 and B.1.351, generally comparable to non-VOC strain.     

Clusters of SARS-CoV-2 Lineage B.1.1.7 Infection after Vaccination with Adenovirus-Vectored and Inactivated Vaccines

A SARS-CoV-2 B.1.1.7 variant of concern (VOC) has been associated with increased transmissibility, hospitalization, and mortality. This study aimed to explore the factors associated with B.1.1.7 VOC infection in the context of vaccination. On March 2021, we detected SARS-CoV-2 RNA in nasopharyngeal samples from 14 of 22 individuals vaccinated with a single-dose of ChAdOx1 (outbreak A, n = 26), and 22 of 42 of individuals with two doses of the CoronaVac vaccine (outbreak B, n = 52) for breakthrough infection rates for ChAdOx1 of 63.6% and 52.4% for CoronaVac. The outbreaks were caused by two independent clusters of the B.1.1.7 VOC. The serum of PCR-positive symptomatic SARS-CoV-2-infected individuals had ~1.8–3.4-fold more neutralizing capacity against B.1.1.7 compared to the serum of asymptomatic individuals. These data based on exploratory analysis suggest that the B.1.1.7 variant can infect individuals partially immunized with a single dose of an adenovirus-vectored vaccine or fully immunized with two doses of an inactivated vaccine, although the vaccines were able to reduce the risk of severe disease and death caused by this VOC, even in the elderly.     

Characteristics of SARS-CoV-2 variants of concern B.1.1.7, B.1.351 or P.1: data from seven EU/EEA countries,weeks 38/2020 to 10/2021

We compared 19,207 cases of SARS-CoV-2 variant B.1.1.7/S gene target failure (SGTF), 436 B.1.351 and 352 P.1 to non-variant cases reported by seven European countries. COVID-19 cases with these variants had significantly higher adjusted odds ratios for hospitalisation (B.1.1.7/SGTF: 1.7, 95% confidence interval (CI): 1.0–2.9; B.1.351: 3.6, 95% CI: 2.1–6.2; P.1: 2.6, 95% CI: 1.4–4.8) and B.1.1.7/SGTF and P.1 cases also for intensive care admission (B.1.1.7/SGTF: 2.3, 95% CI: 1.4–3.5; P.1: 2.2, 95% CI: 1.7–2.8).     

First confirmation of importation and transmission in Spain of the newly identified SARS-CoV-2 B.1.1.7 variant

IntroductionA newly identified SARS-CoV-2 variant, VOC202012/01 originating lineage B.1.1.7, recently emerged in the United Kingdom. The rapid spread in the UK of this new variant has caused other countries to be vigilant.Material and methodsWe based our initial screening of B.1.1.7 on the dropout of the S gene signal in the TaqPath assay, caused by the 69/70 deletion. Subsequently, we confirmed the B.1.1.7 candidates by whole genome sequencing.ResultsWe describe the first three imported cases of this variant from London to Madrid, subsequent post-arrival household transmission to three relatives, and the two first cases without epidemiological links to UK. One case required hospitalization. In all cases, drop-out of gene S was correctly associated to the B.1.1.7 variant, as all the corresponding sequences carried the 17 lineage-marker mutations.ConclusionThe first identifications of the SARS-CoV-2 B.1.1.7 variant in Spain indicate the role of independent introductions from the UK coexisting with post-arrival transmission in the community, since the early steps of this new variant in our country.     

SARS-CoV-2 Variants of Concern Infect the Respiratory Tract and Induce Inflammatory Response in Wild-Type Laboratory Mice

The emergence of new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants of concern pose a major threat to public health, due to possible enhanced virulence, transmissibility and immune escape. These variants may also adapt to new hosts, in part through mutations in the spike protein. In this study, we evaluated the infectivity and pathogenicity of SARS-CoV-2 variants of concern in wild-type C57BL/6 mice. Six-week-old mice were inoculated intranasally with a representative virus from the original B.1 lineage, or the emerging B.1.1.7 and B.1.351 lineages. We also infected a group of mice with a mouse-adapted SARS-CoV-2 (MA10). Viral load and mRNA levels of multiple cytokines and chemokines were analyzed in the lung tissues on day 3 after infection. Our data show that unlike the B.1 virus, the B.1.1.7 and B.1.351 viruses are capable of infecting C57BL/6 mice and replicating at high concentrations in the lungs. The B.1.351 virus replicated to higher titers in the lungs compared with the B.1.1.7 and MA10 viruses. The levels of cytokines (IL-6, TNF-α, IL-1β) and chemokine (CCL2) were upregulated in response to the B.1.1.7 and B.1.351 infection in the lungs. In addition, robust expression of viral nucleocapsid protein and histopathological changes were detected in the lungs of B.1.351-infected mice. Overall, these data indicate a greater potential for infectivity and adaptation to new hosts by emerging SARS-CoV-2 variants.     

Previous SARS-CoV-2 Infection Increases B.1.1.7 Cross-Neutralization by Vaccinated Individuals

With the spread of new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there is a need to assess the protection conferred by both previous infections and current vaccination. Here we tested the neutralizing activity of infected and/or vaccinated individuals against pseudoviruses expressing the spike of the original SARS-CoV-2 isolate Wuhan-Hu-1 (WH1), the D614G mutant and the B.1.1.7 variant. Our data show that parameters of natural infection (time from infection and nature of the infecting variant) determined cross-neutralization. Uninfected vaccinees showed a small reduction in neutralization against the B.1.1.7 variant compared to both the WH1 strain and the D614G mutant. Interestingly, upon vaccination, previously infected individuals developed more robust neutralizing responses against B.1.1.7, suggesting that vaccines can boost the neutralization breadth conferred by natural infection.     

First Detection of SARS-CoV-2 B.1.1.7 Variant of Concern in an Asymptomatic Dog in Spain

Natural SARS-CoV-2 infection in pets has been widely documented during the last year. Although the majority of reports suggested that dogs’ susceptibility to the infection is low, little is known about viral pathogenicity and transmissibility in the case of variants of concern, such as B.1.1.7 in this species. Here, as part of a large-scale study on SARS-CoV-2 prevalence in pets in Spain, we have detected the B.1.1.7 variant of concern (VOC) in a dog whose owners were infected with SARS-CoV-2. The animal did not present any symptoms, but viral loads were high in the nasal and rectal swabs. In addition, viral isolation was possible from both swabs, demonstrating that the dog was shedding infectious virus. Seroconversion occurred 23 days after the first sampling. This study documents the first detection of B.1.1.7 VOC in a dog in Spain and emphasizes the importance of performing active surveillance and genomic investigation on infected animals.     

Brief Report: Prosocial nudges and visual indicators increase social distancing,but authoritative nudges do not

Social distancing reduces the transmission of COVID-19 and other airborne diseases. To test different ways to increase social distancing, we conducted a field experiment at a major US airport using a system that presented color-coded visual indicators on crowdedness. We complemented those visual indicators with nudges commonly used to increase COVID-19–preventive behaviors. Analyzing data from 57,146 travelers, we find that visual indicators and nudges significantly affected social distancing. Introducing visual indicators increased the share of travelers practicing social distancing, and this positive effect was enhanced by introducing nudges focused on personal benefits (“protect yourself”) and public benefits (“protect others”). Conversely, an authoritative nudge referencing the Centers for Disease Control and Prevention (“don’t break CDC COVID-19 guidelines”) did not change social distancing behavior. Our results demonstrate that visual indicators and informed nudges can boost social distancing and potentially curb the spread of contagious diseases.     

Influenza and Other Respiratory Viruses: Impact of nonpharmaceutical interventions on laboratory detections of influenza A and B in Canada

BackgroundThe first coronavirus disease 2019 (COVID-19) case was reported in Canada on January 25, 2020. In response to the imminent outbreak, many provincial and territorial health authorities implemented nonpharmaceutical public health measures to curb the spread of disease. “Social distancing” measures included restrictions on group gatherings; cancellation of sports, cultural and religious events and gatherings; recommended physical distancing between people; school and daycare closures; reductions in non-essential services; and closures of businesses.ObjectivesTo evaluate the impact of the combined nonpharmaceutical interventions imposed in March 2020 on influenza A and B epidemiology by comparing national laboratory surveillance data from the intervention period with 9-year historical influenza season control data.MethodsWe obtained epidemiologic data on laboratory influenza A and B detections and test volumes from the Canadian national influenza surveillance system for the epidemiologic period December 29, 2019 (epidemiologic week 1) through May 2, 2020 (epidemiologic week 18). COVID-19-related social distancing measures were implemented in Canada from epidemiologic week 10 of this period. We compared influenza A and B laboratory detections and test volumes and trends in detection during the 2019–20 influenza season with those of the previous nine influenza seasons for evidence of changes in epidemiologic trends.ResultsWhile influenza detections the week prior to the implementation of social distancing measures did not differ statistically from the previous nine seasons, a steep decline in positivity occurred between epidemiologic weeks 10 and 14 (March 8–April 4, 2020). Both the percent positive on week 14 (p≤0.001) and rate of decline between weeks 10 and 14 (p=0.003) were significantly different from mean historical data.ConclusionThe data show a dramatic decrease in influenza A and B laboratory detections concurrent with social distancing measures and nonpharmaceutical interventions in Canada. The impact of these measures on influenza transmission may be generalizable to other respiratory viral illnesses during the study period, including COVID-19.     

Serum Neutralizing Activity against B.1.1.7, B.1.351, and P.1 SARS-CoV-2 Variants of Concern in Hospitalized COVID-19 Patients

The recent spreading of new SARS-CoV-2 variants, carrying several mutations in the spike protein, could impact immune protection elicited by natural infection or conferred by vaccination. In this study, we evaluated the neutralizing activity against the viral variants that emerged in the United Kingdom (B.1.1.7), Brazil (P.1), and South Africa (B.1.351) in human serum samples from hospitalized patients infected by SARS-CoV-2 during the first pandemic wave in Italy in 2020. Of the patients studied, 59.5% showed a decrease (≥2 fold) in neutralizing antibody titer against B.1.1.7, 83.3% against P.1, and 90.5% against B.1.351 with respect to the original strain. The reduction in antibody titers against all analyzed variants, and in particular P.1 and B.1.351, suggests that previous symptomatic infection might be not fully protective against exposure to SARS-CoV-2 variants carrying a set of relevant spike mutations.     

SARS-CoV-2 variant B.1.1.7 susceptibility and infectiousness of children and adults deduced from investigations of childcare centre outbreaks,Germany, 2021

We investigated three SARS-CoV-2 variant B.1.1.7 childcare centre and related household outbreaks. Despite group cohorting, cases occurred in almost all groups, i.e. also among persons without close contact. Children’s secondary attack rates (SAR) were similar to adults (childcare centres: 23% vs 30%; p = 0.15; households: 32% vs 39%; p = 0.27); child- and adult-induced household outbreaks also led to similar SAR. With the advent of B.1.1.7, susceptibility and infectiousness of children and adults seem to converge. Public health measures should be revisited accordingly.     

Replication Kinetics of B.1.351 and B.1.1.7 SARS-CoV-2 Variants of Concern Including Assessment of a B.1.1.7 Mutant Carrying a Defective ORF7a Gene

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of COVID-19, is a readily transmissible and potentially deadly pathogen which is currently re-defining human susceptibility to pandemic viruses in the modern world. The recent emergence of several genetically distinct descendants known as variants of concern (VOCs) is further challenging public health disease management, due to increased rates of virus transmission and potential constraints on vaccine effectiveness. We report the isolation of SARS-CoV-2 VOCs imported into Australia belonging to the B.1.351 lineage, first described in the Republic of South Africa (RSA), and the B.1.1.7 lineage originally reported in the United Kingdom, and directly compare the replication kinetics of these two VOCs in Vero E6 cells. In this analysis, we also investigated a B.1.1.7 VOC (QLD1516/2021) carrying a 7-nucleotide deletion in the open reading frame 7a (ORF7a) gene, likely truncating and rendering the ORF7a protein of this virus defective. We demonstrate that the replication of the B.1.351 VOC (QLD1520/2020) in Vero E6 cells can be detected earlier than the B.1.1.7 VOCs (QLD1516/2021 and QLD1517/2021), before peaking at 48 h post infection (p.i.), with significantly higher levels of virus progeny. Whilst replication of the ORF7a defective isolate QLD1516/2021 was delayed longer than the other viruses, slightly more viral progeny was produced by the mutant compared to the unmutated isolate QLD1517/2021 at 72 h p.i. Collectively, these findings contribute to our understanding of SARS-CoV-2 replication and evolutionary dynamics, which have important implications in the development of future vaccination, antiviral therapies, and epidemiological control strategies for COVID-19.     

Social distancing decreases an individual’s likelihood of contracting COVID-19

Past research has established the value of social distancing as a means of deterring the spread of COVID-19 largely by examining aggregate level data. Locales in which efforts were undertaken to encourage distancing experienced reductions in their rate of transmission. However, these aggregate results tell us little about the effectiveness of social distancing at the level of the individual, which is the question addressed by the current research. Four months after participating in a study assessing their social distancing behavior, 2,120 participants indicated whether they had contracted COVID-19. Importantly, the assessment of social distancing involved not only a self-report measure of how strictly participants had followed social distancing recommendations but also a series of virtual behavior measures of social distancing. These simulations presented participants with graphical depictions mirroring specific real-world scenarios, asking them to position themselves in relation to others in the scene. Individuals’ social distancing behavior, particularly as assessed by the virtual behavior measure, predicted whether they contracted COVID-19 during the intervening 4 mo. This was true when considering only participants who reported having tested positively for the virus and when considering additional participants who, although untested, believed that they had contracted the virus. The findings offer a unique form of additional evidence as to why individuals should practice social distancing. What the individual does matters, not only for the health of the collective, but also for the specific individual.

Since its emergence in late 2019, the COVID-19 pandemic has had a devastating impact on nations around the world. The negative effects are evident with respect to the shocking number of people who have been infected with this novel coronavirus and the sheer number of deaths, as well as the impact upon nations’ economies. Given the lack of a widely available vaccine, minimizing the spread of COVID-19 has required that people change their behavior. Government officials and public health experts worldwide have urged people to engage in various preventive actions: Wash your hands frequently for at least 20 s, use hand sanitizer when handwashing is not feasible, avoid touching your face, disinfect surfaces that you touch, and wear masks. Perhaps most importantly, they have pleaded that their citizens engage in social distancing—avoid close contact with other people. The mantra “six feet” has been repeated regularly and now appears on signs and floor decals throughout society.Although knowledge regarding SARS-CoV-2 transmission is constantly expanding, much has been learned about the dynamics responsible for its spread (1). Considerable evidence stemming from the investigation of such viruses as SARS, MERS, and SARS-CoV-2 highlights that physical distancing reduces their aerial transmission (e.g., ref. 2). Mathematical models of the spread of COVID-19 in particular (e.g., refs. 3–5) have illustrated the efficacy of social distancing as a means of mitigating its spread. Moreover, recent epidemiological evidence also documents the effectiveness of social distancing at the societal level. For example, a recent analysis involving both the US states and 134 nations revealed that the implementation of social distancing policies was associated with a reduction in COVID-19 spread rates within those locales (6). Similarly, an examination of the daily growth rate in COVID-19 cases across US counties during March and April 2020 found that the imposition of shelter-in-place orders and closures of restaurants, bars, and entertainment-related businesses slowed the spread of COVID-19 (7). Other analyses have found that greater social distancing at the county level, as estimated by smartphone GPS data, is associated with reduced spread of COVID-19 and fewer deaths (8).Yet what remains unknown is the extent to which an individual’s social distancing behavior predicts their personal likelihood of contracting COVID-19. This is a critical theoretical and empirical gap, particularly given that the demonstrated effectiveness of social distancing at the aggregate level does not necessarily mean that individual differences in social distancing behavior will predict whether a given individual contracts the disease. For example, it may be that a “critical mass” of social distancing behavior in a given locale is necessary for any individual-level benefits to emerge. Until that critical level is reached, it is possible that individual differences may matter little for disease transmission.Furthermore, beyond the question of whether individual differences in social distancing behavior predict disease transmission, there is also the critical question of the degree to which these individual differences matter. In other words, what is the size of this effect? Do those who practice social distancing enjoy a notably reduced likelihood of contracting the disease? Or are these effects relatively modest in size? Aggregate data offer little insight into these questions. Indeed, aggregation over a large number of instances may be necessary to observe what might be small effects at the level of the individual.To address this theoretical and empirical gap, the current research pursues a different approach to testing the effectiveness of social distancing—one that focuses not on aggregates but on the level of the individual. Are individuals who engage in social distancing behaviors less likely to contract COVID-19? If so, to what degree? To examine this question, we assessed participants’ (US residents) social distancing behavior at the height of the first wave of the pandemic and then 4 mo later asked them to report whether they had contracted the virus.The assessment of the extent to which individuals practiced social distancing was accomplished by two very different measurement techniques. The standard approach generally employed in social science research, and certainly true of hundreds of recent studies concerning the pandemic (9), is simply to prepare survey questions asking people to report the extent to which they personally practice social distancing. We did precisely the same in the current research.However, what makes our research all the more unique is that we supplemented the self-report measure with a more innovative, behaviorally oriented approach to the assessment of social distancing. We simulated social distancing behavior by presenting participants with graphical depictions that mirrored different real-world scenarios and asking them to position themselves as they personally would in relation to others in the scene. These virtual social distancing scenarios required a concrete, “in-the-moment” behavioral decision, which could vary in the degree to which participants did or did not distance themselves from others. For example, in one scenario participants chose whether to cross a park via a circuitous but isolated path versus a more direct but crowded route. In another, they were presented an aerial image of a crowded beach and asked to click on the spot where they personally would lay down their towel. Yet another presented an interactive image of two people approaching each other in a crosswalk for which participants were asked to move a slider that shifted the walkers from the center of the crosswalk to the distance that they personally would leave between themselves and the other individual. The 10 behavioral scenarios can be viewed at our demonstration website, http://psychvault.org/social-distancing/.We included this virtual behavior distancing measure out of concern for the potential problems that have been documented to be associated with self-reports of behavior. Individuals may overreport their social distancing to convey a socially desirable impression to others and themselves (10–13). Moreover, self-reports may be all the more problematic to the extent that they rely on retrospective memory regarding past behavior (14, 15). By simulating concrete real-world situations that require an immediate decision, the graphical scenarios offer a means, in addition to a self-report, of indexing the extent to which individuals behave in a manner that accords with the principle of social distancing.The present study examines whether both the self-report measure and the virtual behavior measure of social distancing prospectively predict, 4 mo later, whether an individual contracted COVID-19. The data are available on the Open Science Framework: https://osf.io/x79ak/.     

Modeling targeted layered containment of an influenza pandemic in the United States

Planning a response to an outbreak of a pandemic strain of influenza is a high public health priority. Three research groups using different individual-based, stochastic simulation models have examined the consequences of intervention strategies chosen in consultation with U.S. public health workers. The first goal is to simulate the effectiveness of a set of potentially feasible intervention strategies. Combinations called targeted layered containment (TLC) of influenza antiviral treatment and prophylaxis and nonpharmaceutical interventions of quarantine, isolation, school closure, community social distancing, and workplace social distancing are considered. The second goal is to examine the robustness of the results to model assumptions. The comparisons focus on a pandemic outbreak in a population similar to that of Chicago, with approximately 8.6 million people. The simulations suggest that at the expected transmissibility of a pandemic strain, timely implementation of a combination of targeted household antiviral prophylaxis, and social distancing measures could substantially lower the illness attack rate before a highly efficacious vaccine could become available. Timely initiation of measures and school closure play important roles. Because of the current lack of data on which to base such models, further field research is recommended to learn more about the sources of transmission and the effectiveness of social distancing measures in reducing influenza transmission.     

S gene drop-out predicts super spreader H69del/V70del mutated SARS-CoV-2 virus

正Emergence of newer SARS-CoV-2 variants, especially strain B.1.1.7/SARS-CoV-2 VUI 202012/01, discovered in the United Kingdom with H69del/V70del mutation in spike S gene was reported with higher transmissibility of up to 70%[1]. Identification of this variant was sparsely done in India because performing routine diagnosis as well as genomic surveillance using a single kit is the hour of need. To our knowledge, two publications identified the aforesaid mutation by phenomena called S gene drop-out using Applied Biosystems Taq Path COVID-19 Combo kit(Thermo Fisher Scientific, Waltham, USA)[2-4].     

Kinetics of Neutralizing Antibodies of COVID-19 Patients Tested Using Clinical D614G,B.1.1.7, and B 1.351 Isolates in Microneutralization Assays

Increasing evidence suggests that some newly emerged SARS-CoV-2 variants of concern (VoCs) resist neutralization by antibodies elicited by the early-pandemic wild-type virus. We applied neutralization tests to paired recoveree sera (n = 38) using clinical isolates representing the first wave (D614G), VoC1, and VoC2 lineages (B.1.1.7 and B 1.351). Neutralizing antibodies inhibited contemporary and VoC1 lineages, whereas inhibition of VoC2 was reduced 8-fold, with 50% of sera failing to show neutralization. These results provide evidence for the increased potential of VoC2 to reinfect previously SARS-CoV-infected individuals. The kinetics of NAbs in different patients showed similar decline against all variants, with generally low initial anti-B.1.351 responses becoming undetectable, but with anti-B.1.1.7 NAbs remaining detectable (>20) for months after acute infection.     

Phylodynamic Dispersal of SARS-CoV-2 Lineages Circulating across Polish–German Border Provinces

Introduction: The emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has evolved into a worldwide outbreak, with significant molecular evolution over time. Large-scale phylodynamic studies allow to map the virus spread and inform preventive strategies. Aim: This study investigates the extent of binational dispersal and dynamics of SARS-CoV-2 lineages between seven border provinces of the adjacent countries of Poland and Germany to reconstruct SARS-CoV-2 transmission networks. Methods: Following three pandemic waves from March 2020 to the end of May 2021, we analysed a dataset of 19,994 sequences divided into B.1.1.7|Alpha and non-Alpha lineage groups. We performed phylogeographic analyses using the discrete diffusion models to identify the pathways of virus spread. Results: Based on population dynamics inferences, in total, 673 lineage introductions (95% HPD interval 641–712) for non-Alpha and 618 (95% HPD interval 599–639) for B.1.1.7|Alpha were identified in the area. For non-Alpha lineages, 5.05% binational, 86.63% exclusively German, and 8.32% Polish clusters were found, with a higher frequency of international clustering observed for B.1.1.7|Alpha (13.11% for binational, 68.44% German and 18.45% Polish, p < 0.001). We identified key transmission hubs for the analysed lineages, namely Saxony, West Pomerania and Lower Silesia. Conclusions: Clustering patterns between Poland and Germany reflect the viral variant transmission dynamics at the international level in the borderline area. Tracing the spread of the virus between two adjacent large European countries may provide a basis for future intervention policies in cross-border cooperation efforts against the spread of the pandemics.     

SARS-CoV-2 Variant-Specific Infectivity and Immune Profiles Are Detectable in a Humanized Lung Mouse Model

Small animal models that accurately model pathogenesis of SARS-CoV-2 variants are required for ongoing research efforts. We modified our human immune system mouse model to support replication of SARS-CoV-2 by implantation of human lung tissue into the mice to create TKO-BLT-Lung (L) mice and compared infection with two different variants in a humanized lung model. Infection of TKO-BLT-L mice with SARS-CoV-2 recapitulated the higher infectivity of the B.1.1.7 variant with more animals becoming infected and higher sustained viral loads compared to mice challenged with an early B lineage (614D) virus. Viral lesions were observed in lung organoids but no differences were detected between the viral variants as expected. Partially overlapping but distinct immune profiles were also observed between the variants with a greater Th1 profile in VIDO-01 and greater Th2 profile in B.1.1.7 infection. Overall, the TKO-BLT-L mouse supported SARS-CoV-2 infection, recapitulated key known similarities and differences in infectivity and pathogenesis as well as revealing previously unreported differences in immune responses between the two viral variants. Thus, the TKO-BLT-L model may serve as a useful animal model to study the immunopathobiology of newly emerging variants in the context of genuine human lung tissue and immune cells.     

O Impacto da COVID-19 no Diagnóstico de Doenças Cardíacas na América Latina Uma Subanálise do INCAPS COVID

BackgroundThe COVID-19 pandemic has disrupted the delivery of care for cardiovascular diseases in Latin America. However, the effect of the pandemic on the cardiac diagnostic procedure volumes has not been quantified.ObjectiveTo assess (1) the impact of COVID-19 on cardiac diagnostic volumes in Latin America and (2) determine its relationship with COVID-19 case incidence and social distancing measures.MethodsThe International Atomic Energy Agency conducted a worldwide survey assessing changes in cardiac diagnostic volumes resulting from COVID-19. Cardiac diagnostic volumes were obtained from participating sites for March and April 2020 and compared to March 2019. Social distancing data were collected from Google COVID-19 community mobility reports and COVID-19 incidence per country from the Our World in Data.ResultsSurveys were conducted in 194 centers performing cardiac diagnostic procedures, in 19 countries in Latin America. Procedure volumes decreased 36% from March 2019 to March 2020, and 82% from March 2019 to April 2020. The greatest decreases occurred in echocardiogram stress tests (91%), exercise treadmill tests (88%), and computed tomography calcium scores (87%), with slight variations between sub-regions of Latin America. Changes in social distancing patterns (p < 0.001) were more strongly associated with volume reduction than COVID-19 incidence (p = 0.003).ConclusionsCOVID-19 was associated with a significant reduction in cardiac diagnostic procedures in Latin America, which was more related to social distancing than to the COVID-19 incidence. Better balance and timing of social distancing measures and planning to maintain access to medical care is warranted during a pandemic surge, especially in regions with high cardiovascular mortality.