New research has found that symptoms, like brain fog, may be the result of a long COVID brain injury which may lead to cognitive and mental health issues that persist for years. The researchers stated that long COVID-19 can cause the equivalent of 20 years of brain injury.
When people try to claim that COVID-19 is “nothing more than a cold,” in general, colds do not cause brain injury. And since vaccines can reduce the risk of long COVID, this should be another reason to be vaccinated with the safe and effective COVID-19 vaccines.
This article will discuss this new research, reviewing the data and conclusion, to help you understand the seriousness of the link between long COVID-19 and cognitive decline.

Long COVID-19 and brain injury paper
In a paper published on 22 December 2023 in Nature Communications, Benedict Michael, Ph.D., director of the Infection Neuroscience Lab at the University of Liverpool in Liverpool, England, and colleagues found markers of brain injury that are present in the blood many months after COVID-19 infection, despite inflammation blood tests being normal.
The study analyzed samples from over 800 patients hospitalized with COVID-19 from across England and Wales, half of whom with new neurological conditions. Here researchers measured brain injury markers, serum inflammatory proteins (cytokines), antibodies, and brain (neuroglial) injury proteins.
The analysis of these shows that during the acute phase (when symptoms of COVID-19 are developing quickly) there is a production of key inflammatory proteins and brain injury markers, but ongoing robust biomarker evidence of brain (neuroglial) injury in COVID-19 even months after discharge from hospital. Importantly, this was more prominent in patients with neurological dysfunction in the acute phase of the illness and continued in the recovery phase in patients who had suffered acute neurological complications.
To understand the neurological complications of long COVID-19, the researchers measured markers of brain injury, inflammatory mediators, and autoantibodies in 203 hospitalized participants — 111 with acute COVID-19 (1–11 days post-admission) and 92 convalescent sera (56 with COVID-19-associated neurological diagnoses). They compared this group to 60 uninfected control patients.
The researchers found the following:
- The brain deficits found in COVID-19 patients were equivalent to 20 years of brain aging and provided proof of what doctors have feared: that this virus can damage the brain and result in ongoing mental health issues.
- They found that biochemical markers of brain injury, but not immune markers, are elevated in the blood of patients with COVID-19 both early and months after SARS-CoV-2 infection, particularly in those with brain dysfunction or neurological diagnoses.
- An important caveat — this research does not show if the cognitive decline is permanent. It also does not establish whether the brain injury markers can be observed long-term.
Other researchers have found similar brain injury symptoms from long COVID-19. Moreover, brain scans have previously shown atrophy to the brain’s gray matter in COVID-19 patients, likely caused by inflammation from a heightened immune response to the virus rather than from the virus itself.
Summary
As long COVID-19 has become more prevalent, some clinicians have dismissed the “brain fog” symptoms expressed by many patients. However, this new research indicates that there is a clear link between long COVID-19 and brain injury biochemical markers.
Again, this is more information that supports the scientific fact that COVID-19 is dangerous and can cause long-term harm. If you want to protect your brain from this disease, the best and safest way to do so is by getting the COVID-19 vaccine.
Citations
- Michael BD, Dunai C, Needham EJ, Tharmaratnam K, Williams R, Huang Y, Boardman SA, Clark JJ, Sharma P, Subramaniam K, Wood GK, Collie C, Digby R, Ren A, Norton E, Leibowitz M, Ebrahimi S, Fower A, Fox H, Tato E, Ellul MA, Sunderland G, Held M, Hetherington C, Egbe FN, Palmos A, Stirrups K, Grundmann A, Chiollaz AC, Sanchez JC, Stewart JP, Griffiths M, Solomon T, Breen G, Coles AJ, Kingston N, Bradley JR, Chinnery PF, Cavanagh J, Irani SR, Vincent A, Baillie JK, Openshaw PJ, Semple MG; ISARIC4C Investigators; COVID-CNS Consortium; Taams LS, Menon DK. Para-infectious brain injury in COVID-19 persists at follow-up despite attenuated cytokine and autoantibody responses. Nat Commun. 2023 Dec 22;14(1):8487. doi: 10.1038/s41467-023-42320-4. PMID: 38135686; PMCID: PMC10746705.
- Perlis RH, Santillana M, Ognyanova K, Safarpour A, Lunz Trujillo K, Simonson MD, Green J, Quintana A, Druckman J, Baum MA, Lazer D. Prevalence and Correlates of Long COVID Symptoms Among US Adults. JAMA Netw Open. 2022 Oct 3;5(10):e2238804. doi: 10.1001/jamanetworkopen.2022.38804. PMID: 36301542; PMCID: PMC9614581.
