Immune responses against sars-cov-2—questions and experiences

Understanding immune reactivity against SARS-CoV-2 is essential for coping with the COVID-19 pandemic. Herein, we discuss experiences and open questions about the complex immune responses to SARS-CoV-2. Some people react excellently without experiencing any clinical symptoms, they do not get sick, and they do not pass the virus on to anyone else (“sterilizing” immunity). Others produce antibodies and do not get COVID-19 but transmit the virus to others (“protective” immunity). Some people get sick but recover. A varying percentage develops respiratory failure, systemic symptoms, clotting disorders, cytokine storms, or multi-organ failure; they subsequently decease. Some develop long COVID, a new pathologic entity similar to fatigue syndrome or autoimmunity. In reality, COVID-19 is considered more of a systemic immune–vascular disease than a pulmonic disease, involving many tissues and the central nervous system. To fully comprehend the complex clinical manifestations, a profound understanding of the immune responses to SARS-CoV-2 is a good way to improve clinical management of COVID-19. Although neutralizing antibodies are an established approach to recognize an immune status, cellular immunity plays at least an equivalent or an even more important role. However, reliable methods to estimate the SARS-CoV-2-specific T cell capacity are not available for clinical routines. This deficit is important because an unknown percentage of people may exist with good memory T cell responsibility but a low number of or completely lacking peripheral antibodies against SARS-CoV-2. Apart from natural immune responses, vaccination against SARS-CoV-2 turned out to be very effective and much safer than naturally acquired immunity. Nevertheless, besides unwanted side effects of the currently available vector and mRNA preparations, concerns remain whether these vaccines will be strong enough to defeat the pandemic. Altogether, herein we discuss important questions, and try to give answers based on the current knowledge and preliminary data from our laboratories

Practice recommendations for neurovascular ultrasound investigations of acute stroke patients in the setting of the COVID-19 pandemic: an expert consensus from the European Society of Neurosonology and Cerebral Hemodynamics

Background and purpose: Patients with acute ischemic stroke are at high-risk for contracting COVID-19 infection. Additionally, healthcare professionals including neurovascular ultrasound providers are also at risk of being infected by SARS-CoV-2 virus. Yet, preparedness to continue to guarantee hyperacute treatment is vital for patients outcome. In light of this situation, the European Society of Neurosonology and Cerebral Hemodynamic (ESNCH) appointed a task force to provide consensus recommendations for the performance of neurovascular ultrasound investigations in acute ischemic stroke during the COVID-19 pandemic with the aim of protecting both patients and ultrasound providers. Methods: The “ultrasound in acute stroke working group” of the ESNCH examined literature articles and reviews using the following key words: “corona virus” or “COVID-19” or “SARS-CoV-2 virus”, and “acute stroke” or “cerebrovascular disease”, and “ultrasound”. Thereafter, a thorough discussion was conducted with the “education and guidelines working group” of the ESNCH. Results: We propose rapid up-to-date recommendations for healthcare personnel involved in the pre-hospital and intra-hospital assessment of stroke patients, with a particular attention to neurovascular ultrasound performance. Conclusion: The ESNCH provides a guidance summary for the performance of neurovascular ultrasound investigations in acute ischemic stroke in the time of COVID-19. © 2020 European Academy of Neurolog

Practice recommendations for the neurovascular ultrasound investigations of acute stroke patients in the setting of COVID-19 pandemic: an expert consensus from the European Society of Neurosonology and Cerebral Hemodynamics

Since the COVID-19 pandemic stormed into the healthcare systems worldwide, protected stroke pathways have been suggested, in order not to spread the viral infection and ensure hyper-acute treatment. Noteworthy, patients with acute ischemic stroke are at high-risk for contracting SARS-CoV-2 virus, particularly the severe form, because COVID-19 and cerebrovascular diseases share common risk factors. Conversely, among patients hospitalized with SARS-CoV-2 respiratory distress, about 5% might suffer a stroke. During the acute stages of the pandemic, thousands of healthcare professionals have already contracted COVID-19 infection, although the actual number is likely to be higher because healthcare workers are not always tested and protection measures at hospitals are not always readily available. This is the setting in which neurovascular ultrasound providers (physicians, sonographers) should expect to be involved in the care of stroke patients