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PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0261559
Author(s):  
Ali Ghaddar ◽  
Sanaa Khandaqji ◽  
Zeinab Awad ◽  
Rawad Kansoun

Background The massive, free and unrestricted exchange of information on the social media during the Covid-19 pandemic has set fertile grounds for fear, uncertainty and the rise of fake news related to the virus. This “viral” spread of fake news created an “infodemic” that threatened the compliance with public health guidelines and recommendations. Objective This study aims to describe the trust in social media platforms and the exposure to fake news about COVID-19 in Lebanon and to explore their association with vaccination intent. Methods In this cross-sectional study conducted in Lebanon during July–August, 2020, a random sample of 1052 participants selected from a mobile-phone database responded to an anonymous structured questionnaire after obtaining informed consent (response rate = 40%). The questionnaire was conducted by telephone and measured socio-demographics, sources and trust in sources of information and exposure to fake news, social media activity, perceived threat and vaccination intent. Results Results indicated that the majority of participants (82%) believed that COVID-19 is a threat and 52% had intention to vaccinate. Exposure to fake/ unverified news was high (19.7% were often and 63.8% were sometimes exposed, mainly to fake news shared through Watsapp and Facebook). Trust in certain information sources (WHO, MoPH and TV) increased while trust in others (Watsapp, Facebook) reduced vaccination intent against Covid-19. Believing in the man-made theory and the business control theory significantly reduced the likelihood of vaccination intent (Beta = 0.43; p = 0.01 and Beta = -0.29; p = 0.05) respectively. Conclusion In the context of the infodemic, understanding the role of exposure to fake news and of conspiracy believes in shaping healthy behavior is important for increasing vaccination intent and planning adequate response to tackle the Covid-19 pandemic.


Viruses ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 129
Author(s):  
Xenia Snetkov ◽  
Tafhima Haider ◽  
Dejan Mesner ◽  
Nicholas Groves ◽  
Schuyler B. van Engelenburg ◽  
...  

The HIV-1 envelope (Env) is an essential determinant of viral infectivity, tropism and spread between T cells. Lentiviral Env contain an unusually long 150 amino acid cytoplasmic tail (EnvCT), but the function of the EnvCT and many conserved domains within it remain largely uncharacterised. Here, we identified a highly conserved tryptophan motif at position 757 (W757) in the LLP-2 alpha helix of the EnvCT as a key determinant for HIV-1 replication and spread between T cells. Alanine substitution at this position potently inhibited HIV-1 cell–cell spread (the dominant mode of HIV-1 dissemination) by preventing recruitment of Env and Gag to sites of cell–cell contact, inhibiting virological synapse (VS) formation and spreading infection. Single-molecule tracking and super-resolution imaging showed that mutation of W757 dysregulates Env diffusion in the plasma membrane and increases Env mobility. Further analysis of Env function revealed that W757 is also required for Env fusion and infectivity, which together with reduced VS formation, result in a potent defect in viral spread. Notably, W757 lies within a region of the EnvCT recently shown to act as a supporting baseplate for Env. Our data support a model in which W757 plays a key role in regulating Env biology, modulating its temporal and spatial recruitment to virus assembly sites and regulating the inherent fusogenicity of the Env ectodomain, thereby supporting efficient HIV-1 replication and spread.


Author(s):  
Xin Sun ◽  
Shaobo Yang ◽  
Amal A. Al-Dossary ◽  
Shana Broitman ◽  
Yun Ni ◽  
...  

The highly transmissible severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected more than 253 million people, claiming ∼ 5.1 million lives to date. Although mandatory quarantines, lockdowns, and vaccinations help curb viral transmission, there is a pressing need for cost-effective systems to mitigate the viral spread. Here, we present a generic strategy for capturing SARS-CoV-2 through functionalized cellulose materials. Specifically, we developed a bifunctional fusion protein consisting of a cellulose-binding domain and a nanobody (Nb) targeting the receptor-binding domain of SARS-CoV-2. The immobilization of the fusion proteins on cellulose substrates enhanced the capture efficiency of Nbs against SARS-CoV-2 pseudoviruses of the wildtype and the D614G variant, the latter of which has been shown to confer higher infectivity. Furthermore, the fusion protein was integrated into a customizable chromatography with highly porous cellulose to capture viruses from complex fluids in a continuous fashion. By capturing and containing viruses through the Nb-functionalized cellulose, our work may find utilities in virus sampling and filtration towards paper-based diagnostics, environmental tracking of viral spread and reducing viral load from infected individuals. IMPORTANCE The ongoing efforts to address the COVID-19 pandemic center around the development of diagnostics, preventative measures, and therapeutic strategies. In comparison to existing work, we have provided a complementary strategy to capture SARS-CoV-2 by functionalized cellulose materials towards paper-based diagnostics as well as virus filtration in perishable samples. Specifically, we developed a bifunctional fusion protein consisting of both a cellulose-binding domain and a nanobody specific for the receptor-binding domain of SARS-CoV-2. As a proof-of-concept, the fusion protein-coated cellulose substrates exhibited enhanced capture efficiency against SARS-CoV-2 pseudovirus of both wildtype and the D614G mutant variants, the latter of which has been shown to confer higher infectivity. Furthermore, the fusion protein was integrated into a customizable chromatography for binding viruses from complex biological fluids in a highly continuous and cost-effective manner. Such antigen-specific capture can potentially immobilize viruses of interest for viral detection and removal, which contrasts with the common size- or affinity-based filtration devices that bind a broad range of bacteria, viruses, fungi, and cytokines present in blood ( https://clinicaltrials.gov/ct2/show/NCT04413955 ). Additionally, since our work focuses on capturing and concentrating viruses from surfaces and fluids as a means to improve detection, it can serve as an “add-on” technology to complement existing viral detection methods, many of which have been largely focusing on improving the intrinsic sensitivities.


2022 ◽  
Author(s):  
Anneliese Ashhurst ◽  
Matt Johansen ◽  
Joshua Maxwell ◽  
Caroline Ashley ◽  
Anupriya Aggarwal ◽  
...  

Abstract Current vaccines against SARS-CoV-2 substantially reduce mortality, but protection against infection is less effective. Enhancing immunity in the respiratory tract, via mucosal vaccination, may provide protection against infection and minimise viral spread. We tested a novel subunit vaccine in mice, consisting of SARS-CoV-2 Spike protein with a TLR2-stimulating adjuvant, delivered to mice parenterally or mucosally. Both routes of vaccination induced substantial neutralising antibody (nAb) titres, however, mucosal vaccination uniquely generated anti-Spike IgA, increased nAb in the serum and airways, and increased lung CD4+ T-cell responses. TLR2 is expressed by respiratory epithelia and immune cells. Using TLR2 deficient chimeric mice, we determined that TLR2 expression in either compartment facilitated early innate responses to mucosal vaccination. By contrast, TLR2 on hematopoietic cells was essential for optimal lung-localised, antigen-specific responses. In a K18-hACE2 mice, vaccination provided complete protection against disease and sterilising lung immunity against SARS-CoV-2. These data support mucosal vaccination as a strategy to improve protection in the respiratory tract against SARS-CoV-2 and other respiratory viruses.


2022 ◽  
Vol 5 (1) ◽  
pp. 9
Author(s):  
Junjie Liu ◽  
Yong Yang ◽  
Xiaochao Fan ◽  
Ge Ren ◽  
Liang Yang ◽  
...  

The rapid identification of offensive language in social media is of great significance for preventing viral spread and reducing the spread of malicious information, such as cyberbullying and content related to self-harm. In existing research, the public datasets of offensive language are small; the label quality is uneven; and the performance of the pre-trained models is not satisfactory. To overcome these problems, we proposed a multi-semantic fusion model based on data augmentation (MSF). Data augmentation was carried out by back translation so that it reduced the impact of too-small datasets on performance. At the same time, we used a novel fusion mechanism that combines word-level semantic features and n-grams character features. The experimental results on the two datasets showed that the model proposed in this study can effectively extract the semantic information of offensive language and achieve state-of-the-art performance on both datasets.


2022 ◽  
Author(s):  
Eva Mezey ◽  
Lynn Vitale-Cross ◽  
Ildiko Szalayova ◽  
Aiden Scoggins ◽  
Miklos Palkovits

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) infections result in the temporary loss of smell and taste (anosmia and dysgeusia) in about one third of confirmed cases. Several investigators have reported that the viral spike protein receptor is present in olfactory neurons. However, no study has been published to date showing the presence of viral entry sites angiotensin-converting enzyme 2 (ACE2), neuropilin1 (NRP1), and TMPRSS2, the serine protease necessary for priming the viral proteins, in human nerves that are responsible for taste sensation (cranial nerves: VII, IX and X). We used immunocytochemistry to examine three postmortem donor samples of the IXth (glossopharyngeal) and Xth (vagal) cranial nerves where they leave/join the medulla from three donors to confirm the presence of ACE2, NRP1 and TMPRSS2. Two samples were paraffin embedded; one was a frozen sample. In addition to staining sections from the latter, we isolated RNA from it, made cDNA, and performed PCR to confirm the presence of the mRNAs that encode the proteins visualized. All three of the proteins required for SARS-CoV-2 infections appear to be present in the human IXth and Xth nerves near the medulla. Direct infection of these nerves by the COVID-19 virus is likely to cause the loss of taste experienced by many patients. In addition, potential viral spread through these nerves into the adjacent brainstem respiratory centers might also aggravate the respiratory problems patients are experiencing.


2022 ◽  
Author(s):  
Sharon Ovnat Tamir ◽  
Yehuda Schwarz ◽  
Ofer Gluck ◽  
Blake Alkire ◽  
Tal Marom ◽  
...  

Abstract Background: Understanding middle ear anatomy, in addition to endoscopic surgical skill acquisition, is an arduous task. Mastering 3-dimensional conceptualization and surgical dexterity may take many years. The coronavirus pandemic has made training difficult and complicated due to social distancing and risk of aerosolized viral spread in cadaver dissection. In this study we suggest a smartphone-based endoscope ovine head cadaveric dissection which is a simple, safe, and affordable training model for residents as an initial step in otologic endoscopic surgery training.Methods: A stepwise depiction of endoscopic ovine middle ear surgery; from cadaver and equipment acquisition, setting preparation, to surgical explanation and procedural steps. Results: The smartphone-based endoscopic otological ovine dissection model provides a low-cost, easily accessible and easily deployable training model for the novice surgeon world-wide. This model permits the novice surgeon a comprehensive anatomical understanding, middle ear proprioception, as well as a "safe" practicing model for diverse middle ear procedures. Conclusions: The ovine cadaver otological smartphone-based endoscopic surgery training model is an affordable, easy, reproducible, and transportable model, which makes it an ideal model from implementation in both low-middle and high-income countries.


Viruses ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 70
Author(s):  
Eduardo D. Rodríguez-Aguilar ◽  
Jesús Martínez-Barnetche ◽  
Cesar R. González-Bonilla ◽  
Juan M. Tellez-Sosa ◽  
Rocío Argotte-Ramos ◽  
...  

Chikungunya virus (CHIKV) is an alphavirus transmitted by Aedes mosquitoes, which causes Chikungunya fever. Three CHIKV genotypes have been identified: West African, East-Central-South African and Asian. In 2014, CHIKV was detected for the first time in Mexico, accumulating 13,569 confirmed cases in the following three years. Studies on the molecular diversification of CHIKV in Mexico focused on limited geographic regions or investigated only one structural gene of the virus. To describe the dynamics of this outbreak, we analyzed 309 serum samples from CHIKV acute clinical cases from 15 Mexican states. Partial NSP3, E1, and E2 genes were sequenced, mutations were identified, and their genetic variability was estimated. The evolutionary relationship with CHIKV sequences sampled globally were analyzed. Our sequences grouped with the Asian genotype within the Caribbean lineage, suggesting that the Asian was the only circulating genotype during the outbreak. Three non-synonymous mutations (E2 S248F and NSP3 A437T and L451F) were present in our sequences, which were also identified in sequences of the Caribbean lineage and in one Philippine sequence. Based on the phylogeographic analysis, the viral spread was reconstructed, suggesting that after the introduction through the Mexican southern border (Chiapas), CHIKV dispersed to neighboring states before reaching the center and north of the country through the Pacific Ocean states and Quintana Roo. This is the first viral phylogeographic reconstruction in Mexico characterizing the CHIKV outbreak across the country.


2021 ◽  
Vol 119 (2) ◽  
pp. e2112532119
Author(s):  
Peter I. Frazier ◽  
J. Massey Cashore ◽  
Ning Duan ◽  
Shane G. Henderson ◽  
Alyf Janmohamed ◽  
...  

We consider epidemiological modeling for the design of COVID-19 interventions in university populations, which have seen significant outbreaks during the pandemic. A central challenge is sensitivity of predictions to input parameters coupled with uncertainty about these parameters. Nearly 2 y into the pandemic, parameter uncertainty remains because of changes in vaccination efficacy, viral variants, and mask mandates, and because universities’ unique characteristics hinder translation from the general population: a high fraction of young people, who have higher rates of asymptomatic infection and social contact, as well as an enhanced ability to implement behavioral and testing interventions. We describe an epidemiological model that formed the basis for Cornell University’s decision to reopen for in-person instruction in fall 2020 and supported the design of an asymptomatic screening program instituted concurrently to prevent viral spread. We demonstrate how the structure of these decisions allowed risk to be minimized despite parameter uncertainty leading to an inability to make accurate point estimates and how this generalizes to other university settings. We find that once-per-week asymptomatic screening of vaccinated undergraduate students provides substantial value against the Delta variant, even if all students are vaccinated, and that more targeted testing of the most social vaccinated students provides further value.


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