The COVID-19 virus continues to keep secrets, despite the great research effort that is being made.
Every day a new symptom or a new effect appears. And there are still gaps in the knowledge of the means through which the virus is transmitted, the immunity it generates, the sequelae it leaves or the contagion capacity of asymptomatic patients.
But among the doubts and new questions that arise as the knowledge of SARS-CoV-2 advances, we want to focus on the possibility that it can affect the nervous system.
Viruses of the coronavirus family can affect the nervous system
We have the knowledge obtained in research carried out during previous epidemics caused by coronaviruses such as MERS-CoV and SARS-CoV-1. Their results show that coronaviruses can affect the nervous system through various mechanisms.
These include:
- Neurological affectations such as encephalopathies or stroke, consequence of the hyper-inflammatory response and hyper-coagulation induced by the virus;
- Encephalitis produced by direct invasion of the central nervous system;
- Post-infection complications related to the immune response.
Contribution of Spanish neurology
The Albacovid study is the largest to date on the appearance of neurological symptoms in COVID-19 patients. Their results show that of 841 patients admitted for COVID-19 in two hospitals in Albacete during the month of March, more than half manifested neurological symptoms.
Could the virus reach the brain?
The presence of the viruses of the coronavirus family in the central nervous system (specifically in the brain) seems to indicate that they are capable of breaking the cerebral defense constituted by the blood-brain barrier. This protects the brain from the entry of pathogens through the bloodstream.
We know that one of the main effects of SARS-CoV-2 is manifested through inflammatory processes (the so-called ‘cytokine storm’) mainly in the respiratory system. But it also affects other organs, including the nervous system.
It is also known that during neurological disease, brain tissues, including blood vessels and blood, are destroyed. This leads to inflammation and weakening of the blood-brain barrier, altering its permeability. And the process worsens when there is inflammation external to the brain.
Both processes (inflammation outside the brain and weakening of the blood-brain barrier) could create the ideal conditions for the assault of SARS-CoV-2 to the brain.
Cases that meet the criteria for plausible encephalitis resulting from central nervous system infection with SARS-CoV-2 have been reported. But they are very rare cases, and it is important to note that the scientific studies available so far suggest that this virus can only rarely cause true encephalitis or meningoencephalitis associated with evidence of direct viral invasion of the central nervous system.
To date, the SARS-CoV-2 virus has been detected in various organs, but not in the brain. That is, direct invasion of the central nervous system has not been confirmed.
Long-term effects and warning to (young) boaters
At the moment, all the effects that coronaviruses can produce in the brain, their consequences on cognitive functions, and their reversibility or irreversibility are not well known. But we must take into account the neurological effects that the virus can cause in the long term, even in currently asymptomatic infected people.
In these people there are no obvious external symptoms (eg respiratory, feverish or inflammatory). But it could be the case that among these “asymptomatic” patients there are cases in which the possible effects that remain hidden in the short term could produce neurological symptoms.
These pictures can include cognitive impairments at the level of memory or spatial navigation. Or psychiatric disorders caused directly by the viral infection. They could also lead to the development of other pathologies.
Finally, the peripheral nervous system could be seriously affected, and as a consequence the locomotor and respiratory systems, as well as the sense organs.
The brain could become a reservoir for the virus. That is, the virus could persist in the brain without manifesting an apparent neurological disease. Although, as has been seen in other cases, these viruses may finally be involved in such serious diseases as sclerosis or Guillain-Barré syndrome.
In short, the supposed asymptomatology of some infected could be covering up neurological effects that could appear in the long term and be serious.
A campaign: Education in values
Let us remember the campaigns of the General Directorate of Traffic in Spain when the points card was introduced, at a time when serious traffic accidents were constantly increasing. This contribution is a modest cry, a conscientious cry of warning to sailors through the seas of unconsciousness about the effects of COVID-19 and the irresponsibility in the application of measures to stop it.
In practically every country in the world, social distancing and confinement measures have been implemented to cope with the pandemic. Measures that have limited some of our rights, delimiting the border between them and our obligations to others.
Individualism, selfishness and irresponsibility cannot stop the spread of the virus. On the contrary, they facilitate it. In front of them, we advocate for the collective and responsible response of the community as the only means for their defeat.
The epidemiological measures we adopt and the collective, responsible and supportive response are designed not only to collectively protect the human beings and citizens that we are, but also individually the people that we will be in the not too distant future.
This evidence should help us to be able to measure the risks that we take personally and, by extension, those that we make our fellow citizens take. We must work for the sake of responsibility, as well as for the intelligibility. It is a question of attitude, of education, of intelligence, of culture … in short, of social justice, and, therefore, the objective of a new social contract.
Precisely regarding education, an invocation to the latest book by the Spanish neuroscientist Francico Mora. Its title Neuroeducation and reading and its content are a plea to the exciting world of reading. For responsibility, in the face of COVID-19, let’s read more, speak wisely and drink in measure.
A version of this article was published on the website of the Spanish Association for the Advancement of Science (AEAC). 
Jesús Rey Rocha, Scientific Researcher in Science, Technology and Society. Institute of Philosophy of the Higher Council for Scientific Research (IFS-CSIC), Center for Human and Social Sciences (CCHS – CSIC); Emilio Muñoz Ruiz, Research Professor. Institute of Philosophy of the CSIC; Research Unit in Scientific Culture of CIEMAT, Center for Human and Social Sciences (CCHS – CSIC) and Victor Ladero, Senior Scientist of the IPLA-CSIC, Researcher at the Instituto Investigaciones Sanitarias de Asturias (ISPA) and Founding Partner of the Spanish Association for the Advancement of Science (AEAC), Institute of Dairy Products of Asturias (IPLA – CSIC)
This article was originally published on The Conversation. Read the original.
