Australian researchers find long Covid causes brain damage, point to a cure

Long Covid has caused brain damage in tens of thousands of Aussies but a breakthrough by a Sydney researcher points to a possible treatment.

Exclusive: Breakthrough Australian research has identified the nerve toxins behind the brain fog and cognitive impairment suffered by tens of thousands of people with long Covid.

The discovery opens the way for trials of potential treatments including an existing drug for epilepsy and provides hope that new treatments being trialled to treat cognitive damage in cancer patients might also be able to help.

Professor Bruce Brew, a neurologist from St Vincent’s Hospital and the University of NSW, who made the discovery said long Covid patients suffered “slow thought processes and confusion which is very similar to a Traumatic Brain Injury.”

This brain injury persists for at least 12 months his research to be presented at the National Brain Injury Conference later this month.

Neurologist Professor Bruce Brew from St Vincent’s Hospital and the UNSW.

One in five of the 128 long Covid patients in his ADAPT study have cognitive issues he has found are linked to the Kynurenine pathway in the human body.

This pathway is involved in providing the body with energy, in balancing mood and is critical in dampening down the immune system.

When it is activated by an infection it can raise levels of chemicals called quinolinic acid and 3 Hydroxyanthranilic Acid (3HAA).

“When it’s excessively activated, in the context of infections, it will cause neurological effects, it will induce neurotoxicity, it’ll kill or injure nerve cells,” Prof Brew said.

He hopes larger studies will prove blood tests for raised levels of these chemicals could be used as a biomarker for long Covid brain injury and help guide treatment.

The discovery also provides a target for potential treatments.

He said there are currently phase one and phase two studies of drugs that target this same pathway in treating cancer patients that potentially could be used.

“And there are some intriguing data that you could potentially repurpose some drugs (used to control seizures) as they have off target effects, at least in cell culture on this,” he said.

The long Covid clinic at St Vincent's Hospital in Darlinghurst Sydney. Picture: Ryan Osland

Nine in 10 of the long Covid patients in his study had very mild cases of Covid and did not need hospital treatment.

But months after clearing the infection they suffer debilitating symptoms that prevent them from working or functioning normally.

One vaccinated patient who caught Covid used to run a successful business but is no longer able to work because he was no longer able to understand the contracts that were being drawn up, Professor Brew said.

A senior legal practitioner found the brain injury is so significant he has had to take time off work.

“I think that the public have not been fully informed (about the long term effects of Covid),” Prof Brew said.

“The focus has been on deaths and ICU admissions, they are the parameters by which they judge whether Covid is still a problem or not,” he said.

“The functional impact of milder cases of Covid on patients wellbeing and their economic contribution to society has been completely missed”.

Common symptoms of long Covid in the UK were:

– Fatigue

– Loss of smell

– Shortness of breath

– Brain fog, difficulty concentrating

– Heart palpitations

– Pins and needles, numbness

Originally published as Australian researchers find long Covid causes brain damage, point to a cure