The emergence of a novel coronavirus (SARS‐CoV‐2) disease and their neuroinvasive propensity may affect in COVID‐19 patients

Abstract

An outbreak of a novel coronavirus (SARS-CoV-2) infection has recently emerged and rapidly spreading in humans causing a significant threat to international health and the economy. Rapid assessment and warning are crucial for an outbreak analysis in response to serious public health. SARS-CoV-2 shares highly homological sequences with SARS-CoVs causing highly lethal pneumonia with respiratory distress and clinical symptoms similar to those reported for SARS-CoV and MERS-CoV infections. Notably, some COVID-19 patients also expressed neurologic signs like nausea, headache, and vomiting. Several studies have reported that coronaviruses are not only causing respiratory illness but also invade the central nervous system through a synapse-connected route. SARS-CoV infections are reported in both patients and experimental animals' brains. Interestingly, some COVID-19 patients have shown the presence of SARS-CoV-2 virus in their cerebrospinal fluid. Consideringthe similarities between SARS-CoV and SARS-CoV-2 in various aspects, it remains to clarify whether the potent invasion of SARS-CoV-2 may affect in COVID-19 patients. All these indicate that more detailed criteria are needed for the treatment and the prevention of SARS-CoV-2 infected patients. In the absence of potential interventions for COVID-19, there is an urgent need for an alternative strategy to control the spread of this disease. K E Y

The Neurological Complexities and Prognosis of COVID-19

“…COVID-19 is thought to cause an inflammatory reaction weakening the blood-brain barrier allowing the virus to enter the CNS; the blood-CSF barrier of the choroid plexus is also weakened during this inflammatory response [5]; this is accomplished via disruption of ACE2 receptors of the endothelial cells [5,9,16,17,42]. Expression of ACE2 receptors is also seen on the heart, kidneys, small intestines, testes, brain, and lungs; the level of expression varies regionally [18,19,43]. Binding of COVID-19 to endothelial cells induces a massive inflammatory response causing an increase in inflammatory mediators such as TNF-alpha, and interleukin 6 (IL-6) [44].…”

SARS-CoV-2 and the Nervous System: From Clinical Features to Molecular Mechanisms

“…The differences in the sequence of spike proteins between SARS-CoV and SARS-CoV-2 will enable scientists to identify epitopes in COVID-19 patients for the development of monoclonal antibodies against this virus. Basic research studies on SARS-CoV-2 and host interactions are the key to several unanswered questions in the prevention and control of the disease, including the challenging question of why not all patients with COVID-19 show neuroinvasion and why, among those experiencing neuroinvasion, not all show neurotropism or neurovirulence [136]. Moreover, the difference in terms of neurological involvement and pathomechanisms between the current pandemic and the SARS and MERS infections needs to be further studied.…”

Comment on “The neuroinvasive potential of SARS‐CoV‐2 may play a role in the respiratory failure of COVID‐19 patients”

“…This is supported by the recently published study by Paniz‐Mondolfi et al, 6 that confirmed by using electron microscopy, the presence of viral particles showing typical morphological properties of betacoronavirus 6 Another aspect that should be investigated is the exact route by which the virus reaches the brain areas. Authors of the article and a recent review performed by Yashavantha Rao and Jayabaskaran 7 reported that CoVs may first invade peripheral nerve terminals, and then gain access to the CNS via a synapse‐connected route, they state on contrary, that, hematogenous or lymphatic route seems impossible, especially in the early stage of infection. However, it is not excluded that when the virus load becomes important in general circulation, it could reach several brain parts, notably at the level of circumventricular organs (CVO), areas lacking a blood‐brain‐barrier (BBB).…”