SARS-CoV-2 is an enveloped positive-stranded RNA virus that consists of four structural proteins including spike glycoprotein, envelope protein, membrane protein, and nucleocapsid protein.
Just when we thought the SARS-CoV-2 virus couldn't get any more insidious, a new study from investigators at the Yale School of Medicine describes the mechanisms that allow the coronavirus to directly infect the central nervous system.
ThinkStock PhotosFour common cold-causing coronaviruses have been circulating in humans for a long time and nearly everyone is infected at a young age. "Those durations may be very different".
Co-senior author Kaya Bilguvar, an associate professor at Yale School of Medicine, said: "Our study clearly demonstrates that neurons can become a target of SARS-CoV-2 infection, with devastating consequences of localised ischaemia in the brain and cell death". However, researchers are still figuring out how those components translate to protection against disease or transmission.
Although COVID-19 is considered to primarily be a respiratory disease, SARS-CoV-2 can affect many other organs in the body, including, in some patients, the central nervous system, where the infection is associated with a variety of symptoms ranging from headaches and loss of taste and smell to impaired consciousness, delirium, strokes, and cerebral hemorrhage.
The scientists said that nearly everyone catches one of the endemic cold coronaviruses during childhood, often before the age of 5, which gives partial immunity to adults who become reinfected later in life.
The model predicts that the infection fatality ratio for SARS-CoV-2 may fall below that of seasonal influenza (0.1 percent), once an endemic steady-state is reached.
Lavine developed the model, together with Bjornstad and Rustom Antia, PhD, Samuel C. Dobbs professor of biology at Emory University and Emory Vaccine Center.
A safe and effective vaccine against COVID-19 could save hundreds of thousands of lives in the first year or two of vaccine roll-out, but continued mass vaccination may be less critical once SARS-CoV-2 becomes endemic, the authors say.
The researchers also noted that if primary infections of children are mild when the virus becomes endemic, widespread vaccination may not be necessary.
Targeted vaccination in vulnerable subpopulations may still save lives, they said.
The now available data suggests that reinfection rarely occurs within 90 days of the first (initial) infection. There are exceptions on the individual level, with some experiencing rare complications such as MIS-C (multisystem inflammatory syndrome in children).
As a new, more infectious strain of SARS-CoV-2 spreads further from the United Kingdom and across the United States, the U.S. Food and Drug Administration (FDA) is advising that its impact on molecular tests will likely be low, with three approved tests now affected.