Researchers warn that COVID-19’s effects on the central nervous system may cause a rise in the incidence of Parkinson’s disease
Past influenza pandemics have shown that viruses are capable of causing permanent changes in the brain through harm to the central nervous system, and early studies show COVID-19 likely operates in the same way.
Following the 1918 influenza pandemic, researchers found significant correlations between those who recovered from the flu and went on to develop encephalitis lethargica, a disease often referred to as sleeping sickness that leaves patients stiff and speechless. An Oxford University study also found those born around the time of the pandemic had double the usual risk for Parkinson’s disease in later life.
Now a group of researchers in Brazil is warning that the current pandemic is likely to contribute to an increase in the incidence of Parkinson’s disease. The disease is already expected to affect more people in coming decades as lifespans grow longer on average, with 14 million cases projected for 2040.
Publishing in the Journal of Parkinson’s Disease, researchers from the Federal University of São Paulo noted that symptoms such as the loss of taste and smell, and encephalitis—excessive inflammation in the brain—indicate that SARS-CoV-2 is capable of invading the central nervous system.
“Although it is obviously too early to know what the long-term consequences of COVID-19 will be on the brain, the clinical psychiatry and neurology research communities definitely need to be vigilant in monitoring how those who recover from moderate and severe COVID-19 fare in the future,” said Patrik Brundin, the co-editor-in-chief of the medical journal.
“For Parkinson’s disease [PD], there is mounting evidence that both inflammation and infections are associated with elevated risk for PD later in life,” he said.
Symptoms associated with Parkinson’s have also been found among those who recovered from the H1N1 influenza virus, as well as Coxsackie virus, West Nile virus, Japanese encephalitis B, and HIV. Researchers believe viruses such as these harm the brain either directly, by entering the central nervous system, or indirectly, by creating inflammation in the brain.