Scientists warn of potential wave of COVID-linked brain damage
"Whether we will see an epidemic on a large scale of brain damage linked to the pandemic – perhaps similar to the encephalitis lethargica outbreak in the 1920s and 1930s after the 1918 influenza pandemic – remains to be seen," said Michael Zandi, from UCL's Institute of Neurology, who co-led the study.
https://mobile.reuters.com/article/amp/idUSKBN24837S
https://academic.oup.com/brain/article/doi/10.1093/brain/awaa240/5868408
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The disease attacks the brain, leaving some victims in a statue-like condition, speechless and motionless. Between 1915 and 1926, an
epidemic of encephalitis lethargica spread around the world. Nearly five million people were affected, a third of whom died in the acute stages. Many of those who survived never returned to their pre-existing "aliveness".
They would be conscious and aware – yet not fully awake; they would sit motionless and speechless all day in their chairs, totally lacking energy, impetus, initiative, motive, appetite, affect or desire; they registered what went on about them without active attention, and with profound indifference. They neither conveyed nor felt the feeling of life; they were as insubstantial as ghosts, and as passive as zombies.
No recurrence of the epidemic has since been reported, though isolated cases continue to occur.
https://en.wikipedia.org/wiki/Encephalitis_lethargica