While COVID-19 continues to be energetic in a number of western nations, its severity has diminished. A vexing problem nonetheless is Long COVID, a set of long-term well being issues that linger for a number of months following restoration from the an infection. A latest Harvard research evaluating contaminated and non-infected people, reported a ten% danger of getting Long COVID.
A distinguished Long COVID symptom is brain fog, which includes issue focusing, reminiscence impairment and challenges in decision-making. A latest research from Stony Brook University within the U.S., utilising cognitive evaluation exams, recognized a big mental decline following COVID. This was notably pronounced amongst these with Long COVID. The precise mechanism stays unclear, however UK Biobank MRI research had demonstrated shrinking of components of the brain following COVID-19.
In this context, researchers from the University of Queensland and Macquarie University of Australia, in collaboration with the University of Helsinki lately made some startling discoveries. The outcomes have been revealed within the journal Science Advances.
Using specialised laboratory cells that mimic the human brain they discovered that an infection by the SARS-CoV-2 virus resulted in particular person brain cells fusing collectively as one. This might occur between two neurons, two glial cells or between a neuron and a glial cell. It might additionally contain greater than two cells.
By measuring the influx of calcium ions into the cell, they additional demonstrated that the method of fusion additionally affected their operate. Instead of firing individually, the fused neurons fired unexpectedly. This might disrupt communication between nerve cells. Interestingly, the cells didn’t die.
In impact, they found a new illness state of the brain in COVID-19, the place the cells are structurally and functionally altered, but stay alive. This is distinct from the beforehand identified outcomes of viral an infection of the brain, that are cell loss of life and irritation. Apart from SARS-CoV-2, which is understood to enter the brain by disrupting the blood-brain barrier, viruses reminiscent of rabies, HIV and Nipah are additionally able to infecting the brain.
The scientists then went on to check the mechanism of cell fusion. When the virus infects a cell, it causes fusion proteins to be expressed on the floor of cells. These proteins latch on to a neighbouring cell, ultimately the 2 cells changing into one.
Fusion of brain cells not solely alters the construction of the complicated, but in addition makes the cells dysfunctional. This course of is named syncytium formation, whereby the parts of 1 cell freely circulate into others. Viruses use this as a intelligent technique for cell-to-cell unfold, whereas staying out of attain of antibodies that lurk exterior the cells. COVID-19 is understood to induce the identical impact in lung cells.
The SARS-CoV-2 virus makes use of its spike protein for cell fusion. However, the spike protein used within the vaccine, being an altered model of the unique, just isn’t fusogenic. Therefore, there isn’t any concern of such a factor occurring after vaccination.
The prognosis of Long COVID is being studied. While some people get well after a number of months, the outlook has been much less optimistic for a considerable variety of individuals. Being an all-new illness beforehand unknown to man, data about COVID-19 will proceed to evolve.
(Rajeev Jayadevan is co-chairman, National IMA COVID Task Force)