A team of international researchers may have uncovered the cause of the neurological conditions seen in patients with long-COVID, such as brain fog.

The team from the Swinburne University of Technology and La Trobe University in Australia and Luxembourg University in Luxembourg revealed that fragments of proteins from the SARS-CoV-2 virus can form amyloid clumps in the brain that look similar to the amyloids found in patients with neurodegenerative diseases such as Alzheimer's and Parkinson's.

Further, the study published in the journal Nature Communications showed that these amyloids are highly toxic to brain cells. To understand, the team designed, performed and analysed the biochemical flow cytometry assays used to determine the mechanism of brain cell death triggered by the amyloids and assisted with the physical characterisation of the amyloids at the Australian Synchrotron.

"If further studies are able to prove that the formation of these amyloids is causing long-COVID then anti-amyloid drugs developed to treat Alzheimer's might be used to treat some of the neurological symptoms of long-COVID," said Dr Mirren Charnley, a postdoctoral researcher at Swinburne. Long-COVID is marked by neurological symptoms, such as memory loss, sensory confusion, severe headaches, and even stroke.

These neurological symptoms are similar to the early stages of neurodegenerative diseases such as Alzheimer's and Parkinson's, which are characterised by the presence of clumps of ordered proteins" known as amyloids - in the brain. The long-COVID symptoms can persist for months after the infection is over. While there is evidence that the virus can enter the brain of infected people, the precise mechanisms causing these neurological symptoms are unknown.