A major new review from Yale (Moen, Baker, Iwasaki, 2025) offers the most comprehensive picture yet of what SARS-CoV-2 does to the nervous system.
The conclusion is stark:
Long COVID is a chronic neuroimmune disorder affecting brain, spinal cord, and peripheral nerves.🧵
Warning Sign #1: The pandemic didn’t end - it just changed shape.
The virus keeps evolving. The acute symptoms may fade.
But for many, the infection never truly ends.
Even young, previously healthy people experience:
mental fog,
dizziness when standing,
sensory disturbances,
exhaustion after minimal effort,
racing heart.
That’s Long COVID.
Warning Sign #2: The virus leaves behind molecular debris - and the immune system won’t let it go.
Sometimes it’s spike protein fragments in the blood.
Sometimes viral RNA in the olfactory bulb or even the skull.
This triggers persistent immune alarms:
T cells get activated
Inflammation spreads to the brain
Neuronal connections start breaking down
The war continues - long after the virus is gone.
Warning Sign #3: The brain gets sick - even when standard scans look “normal.”
MRI often misses it. But PET imaging shows:
reduced glucose metabolism in the brainstem,
limbic inflammation,
microglia digesting synapses.
Patients say:
“I know what I want to say, but I can’t get it out.”
It’s inflammatory disruption of higher brain function.
Warning Sign #4: It’s not just the brain - the body’s autopilot system begins to fail.
The autonomic nervous system - which controls heart rate, blood pressure, digestion - goes haywire.
Blood pools in the legs; the brain is starved of oxygen.
POTS, dizziness, blackouts, heat intolerance
Even the vagus nerve - the main communication line between brain and body - shows structural damage in some studies.
Warning Sign #5: The immune system may start attacking the nervous system itself.
After infection, some people develop autoantibodies:
against adrenergic receptors,
against cholinergic synapses,
against neurons.
In experiments, these antibodies from Long COVID patients were transferred to mice - and caused neurological symptoms.
This isn’t just immune activation. It’s autoimmunity.
Warning Sign #6: Smell loss isn’t just a quirky symptom - it’s a red flag.
Olfactory tissue often shows:
inflammation,
neuronal destruction,
lingering T cells months after infection.
Even after viral clearance, the damage and local immune activity can persist - blocking recovery.
Smell loss may signal long-term damage to the central nervous system.
Warning Sign #7: Spike protein isn't just debris - it can fuel clotting and inflammation.
Persistent spike fragments have been found in blood and even skull tissue months post-infection.
They bind fibrin - form resistant microclots
These can obstruct capillaries, disrupt brain perfusion, and trigger microglial activation, cause ischemia-reperfusion injury
Even without active virus, brain tissue can be damaged by the aftermath of infection.
Warning Sign #8: SARS-CoV-2 may accelerate brain aging.
Evidence from autopsies, mice, and imaging shows:
damage to dopamine neurons,
loss of neurogenesis in the hippocampus,
inflammatory profiles resembling Parkinson’s and Alzheimer’s.
For some, COVID acts as an accelerant for neurodegenerative processes.
Warning Sign #9: No one is exempt. Not the young. Not the recovered.
Reinfections raise the risk.
Immunological imprinting may alter long-term responses.
Long COVID is not rare - it’s the aftermath of a system-wide disruption.
With no diagnostic test.
No cure.
And millions affected globally.
Bottom line: Long COVID isn’t “just fatigue.”
It’s:
chronic neuroinflammation,
immune dysregulation,
vascular dysfunction,
autonomic breakdown.
It’s a warning that infectious disease can leave lasting biological scars - not just in “high-risk” groups, but in anyone. @szupraha @ZdravkoOnline
This study suggests that in some patients, COVID-19 triggers a long-term process of vascular and cardiac injury that can gradually increase pulmonary pressure, strain the right ventricle, and raise the risk of death in the following years🧵
The study followed 480 hospitalized patients (240 moderate, 240 severe) for one year after discharge. It assessed heart function using echocardiography and measured biomarkers of vascular inflammation.
In severe COVID-19, right-ventricular function was already significantly worse at the first study examination. Over the following year, pulmonary artery pressure increased by 17.8% in severe cases and 7.1% in moderate cases!
If normal population plasma truly carries more low-grade inflammation, this study hints at a fork in the road.
Either we lower the bar and call it a new normal,
or this is a hidden population burden that will surface later as comorbidities🧵
A new study on the cytokine IL-32 after COVID-19 points directly at this uncomfortable question.
The authors analyzed nearly 1,000 healthy blood donors sampled before and during the pandemic, plus 212 hospitalized COVID-19 patients.
The result is consistent - plasma collected after 2020 shows systematically higher IL-32 levels compared to pre-pandemic plasma.
A new population-level study from Singapore looked at 1.4 million COVID cases in a setting with >90% booster coverage.
Result - multi-organ Long COVID largely attenuates.
But the brain remains an exception.
The study tracked new medical diagnoses 31–300 days after infection across Delta and multiple Omicron waves (BA.1/2, BA.4/5, XBB).
Across variants, most organ systems normalize.
Neurocognitive diagnoses do not.
This study does not tell us what exactly causes long COVID or ME/CFS, nor does it test clinical symptoms like PEM.
But it may tell us something just as important - what type of biological problem this likely is..🧵
The authors isolated immunoglobulins (IgG) from people with post-infectious ME/CFS, including post-COVID ME/CFS, and tested what these antibodies do to healthy cells.
In a subset of patients, these IgG alter the behavior of endothelial cells and their mitochondria.
Not by killing the cells or shutting down ATP production.
This isn’t a new comparison.
For years, parallels between NeuroHIV and neuro-COVID/Long COVID have been discussed across fields.
What’s new is that they are now formally described as shared CNS mechanisms, not just analogy!🧵
Just a few years ago, parallels like
HIV - SARS-CoV-2
HAND - brain fog/neuro-LC
microglia - chronic inflammation
vasculature - cognition
were treated mainly as interesting analogies. With caution not to overstate them.
This new review formalizes the shift. These parallels are not Twitter pattern recognition, but convergent CNS phenotypes following viral insults.
A new review shows they are biologically grounded similarities.
A new review links Alzheimer’s disease, Parkinson’s disease, and COVID-19 through a shared core - neuroinflammation + oxidative stress.
The same pathways, the same immune nodes, the same vulnerabilities of the brain🧵
Key players.
Microglia (the brain’s innate immune cells) and neutrophils (peripheral rapid responders).
When the blood–brain barrier (BBB) is disrupted, neutrophils enter the CNS and inflammation becomes self-amplifying.
Neutrophils can form NETs (neutrophil extracellular traps - DNA + histones + enzymes like MPO/elastase).
In the brain, NETs mean oxidative damage, mitochondrial stress, neuronal injury - and further microglial activation. A vicious cycle.