Surgical treatment of tension pneumomediastinum in patients with covid-19 at the field hospital: a case series.

BACKGROUND: Tension pneumomediastinum is one of the most serious complications in COVID-19 patients with respiratory distress requiring invasive mechanical ventilation. This complication can lead to rapid hemodynamic instability and death if it is not recognized in a timely manner and intervenes promptly. CASE PRESENTATION: We reported 7 COVID-19 patients with tension pneumomediastinum at a field hospital. All patients were critically ill with ARDS. These 7 patients, including 3 females and 4 males in this series, were aged between 39 and 70 years. Tension pneumomediastinum occurred on the first day of mechanical ventilation in 3 patients and later in the course of hospital stay, even 10 days after being intubated and ventilated. The tension pneumomediastinum caused hemodynamic instability and worsened respiratory mechanics with imminent cardiopulmonary collapse. In this series, we used two surgical techniques: (i) mediastinal decompression by suprasternal drainage with or without simultaneous pleural drainage in the first two cases and (ii) mediastinal drainage via suprasternal and subxiphoid incisions in 5 patients. The surgical procedures were feasible and reversed the pending cardiopulmonary collapse. Four patients had a favorable postprocedural period and were discharged from the intensive care center. Both patients undergoing suprasternal drainage died of failed/recurrent tension pneumomediastinum and nosocomial infection. Only one in five patients who underwent mediastinal drainage via suprasternal and subxiphoid incisions died of septic shock secondary to ventilator-associated pneumonia. CONCLUSION: Tension pneumomediastinum was a life-threatening complication in critically ill COVID-19 patients requiring mechanical ventilation. Surgical mediastinal decompression was the salvage procedure. The surgical technique of mediastinal drainage via suprasternal and subxiphoid incisions proved an advantage in tension relief, hemodynamic improvement and mortality reduction.

Ethiopian Healthcare Workers' Experiences During the COVID-19 Pandemic (preprint)

Background: The COVID-19 pandemic has caused widespread health and socioeconomic disruptions around the world. Understanding the impact that this crisis has had on health workers and the delivery of routine health care services within countries provides evidence on pandemic preparedness and response. Here, we conduct an investigation into these factors for the Ethiopian context. Methods and findings: We conducted an online cross-sectional survey with Ethiopian health care professionals between August 27 and October 10, 2020 via existing research networks. The variables of interest were confidence in COVID-19 related knowledge, training and experience, the adoption of precautionary health practices, risk perceptions, and respondent concerns. The majority of surveyed health care professionals in Ethiopia reported seeing fewer patients than usual during the COVID-19 crisis, gaps in pandemic training, inadequate access to personal protective equipment (PPE) and barriers to accessing COVID-19 testing. Most health care professionals were also deeply concerned and worried about their own COVID-19 risks and the likelihood that they would transmit the disease to others. Conclusions: Our study findings point to a possible reduction in routine health care services during the COVID-19 pandemic and gaps in pandemic preparedness in Ethiopia. The ministry of health and other stakeholders should work towards improving access to PPE and testing, and identify approaches to ensure that essential healthcare provision (such as immunizations) is not disrupted during crises akin to the COVID-19 outbreak.

Alternating Minimization for Computed Tomography with Unknown Geometry Parameters (preprint)

Due to the COVID-19 pandemic, there is an increasing demand for portable CT machines worldwide in order to diagnose patients in a variety of settings. This has led to a need for CT image reconstruction algorithms that can produce high quality images in the case when multiple types of geometry parameters have been perturbed. In this paper we present an alternating minimization algorithm to address this issue, where one step minimizes a regularized linear least squares problem, and the other step minimizes a bounded non-linear least squares problem. Additionally, we survey existing methods to accelerate convergence of the algorithm and discuss implementation details. Finally, numerical experiments are conducted to illustrate the effectiveness of the algorithm.

Gender and Ebola in Eastern Democratic Republic of the Congo: Pathways to Protective Behavioral Outcomes During the 2018-2020 Ebola Outbreak (preprint)

Background: The Democratic Republic of the Congo (DRC) witnessed the world’s second largest Ebola Virus Disease (EVD) outbreak killing 2290 individuals, with women disportionately infected (57% of all cases) despite no evidence on differential biological risk for EVD. We assessed if men and women differ in personal protective behaviors (vaccine acceptance, health-seeking behaviors, physical distancing) and the mediating role of gender differences in levels of EVD information and knowledge, perceived disease risk, and social relations. Methods: We conducted a multi-stage cluster survey of 1395 individuals in North Kivu between 20 April – 10 May, 2019, a period of high transmission in the sampled region of DRC. We conducted path analyses using a structural equation modeling framework to examine associations among variables as hypothesized. Findings: We found associations between gender and all EVD preventive behavioral outcomes, with evidence for the mediating role of EVD knowledge and belief in rumors. Men reported greater EVD accuracy compared to women. Greater EVD knowledge accuracy was associated with increases in vaccine acceptance, formal care seeking, and self-protection behaviors. Lower belief in rumors led to greater vaccine acceptance, and greater EVD information awareness led to increased adoption of self-protection behaviors. Interpretation: In any response to infectious disease, such as the current COVID-19 pandemic, it is critical to not only design gender-sensitive communication and vaccination strategies, but also to engage women and the community as a whole in the response.Funding: The Enhanced Learning and Research for Humanitarian Assistance (ELRHA) and United Nations Development Programme (UNDP) provided funding for the study.Declaration of Interest: We declare no competing interests.Ethical Approval: The survey was approved by Brigham and Women’s Hospital Human Research Committee and the Research Center on Democracy and Development in Africa, Free university of the Great Lakes Countries in the Democratic Republic of the Congo.

Polyspecific CD8+ α/βT-Cells that Respond to Multiple Viruses and Drive COVID-19 Outcome (preprint)

Randomly generated T cell receptors (TCRs) selected during thymopoiesis form a repertoire of about 108 unique TCRs per individual. How these diverse TCRs can effectively handle a countless and evolving set of infectious agents is a central question of immunology. The paradigm is that a diverse enough repertoire of TCRs should always provide a proper, though rare, specificity for any given need. We analyzed the generation and use of TCR in humans using deep and single-cell sequencing. We found that thymopoiesis releases a large population of CD8+ T cells harboring diverse and polyspecific α/βTCRs that can each recognize and respond to multiple unrelated viral peptides, notably from EBV, CMV and influenza. These TCRs participate in a first-line response to vaccination and infection, including to SARS-CoV-2 for which they predict the infection outcome. Our results support an evolutionary selection of polyspecific α/βTCRs for broad antiviral responses and heterologous immunity.Funding: This work was primarily funded by the TRiPoD ERC-Advanced EU (322856) grant to DK.The LabEx Transimmunom (ANR-11-IDEX-0004-02) and RHU iMAP (ANR-16-RHUS-0001) grants also contributed.Conflict of Interest: The authors declare no competing financial interests.Ethical Approval: Thirteen human thymus samples were obtained from organ donors undergoing surgery (Department of Cardiac Surgery, Pitié-Salpêtrière Hospital, France) after approval by the Agence de Biomédecine and the Ministry of Research.

Human thymopoiesis produces polyspecific CD8+ α/β T cells responding to multiple viral antigens (preprint)

T cell receptors (TCRs) are formed by stochastic gene rearrangements, theoretically generating >10 19 sequences. They are selected during thymopoiesis, which releases a repertoire of about 10 8 unique TCRs per individual. How evolution shaped a process that produces TCRs that can effectively handle a countless and evolving set of infectious agents is a central question of immunology. The paradigm is that a diverse enough repertoire of TCRs should always provide a proper, though rare, specificity for any given need. Expansion of such rare T cells would provide enough fighters for an effective immune response and enough antigen-experienced cells for memory. We show here that human thymopoiesis releases a large population of CD8 + T cells harboring α/β paired TCRs that (i) have high generation probabilities and (ii) a preferential usage of some V and J genes, (iii) are shared between individuals and (iv) can each recognize and be activated by multiple unrelated viral peptides, notably from EBV, CMV and influenza. These polyspecific T cells may represent a first line of defense that is mobilized in response to infections before a more specific response subsequently ensures viral elimination. Our results support an evolutionary selection of polyspecific α/β TCRs for broad antiviral responses and heterologous immunity.