Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), may have long term effects on the brain and nervous system, according to a review published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.

The COVID-19 pandemic has caused over 1.87 million deaths and there have been more than 85.9 million confirmed cases worldwide, according to the World Health Organization. According to the study authors, flulike diseases have been associated with brain disorders since the flu pandemic of 1917 and 1918. Investigators say that it is becoming clear that the damage done by the pandemic will not be limited to acute effects, such as delirium while in the hospital.

The study will collect data over the next 2 to 3 years with initial results expected in early 2022. The study will be made up of 2 groups of enrollees, the first of which will be drawn from the pool of confirmed COVID-19 cases worldwide. The second group of enrollees will consist of those participating in current studies. Participants we be evaluated on a host of cognitive and behavioral measures at an initial appoint and at 6, 9, and 18 months.

According to the review, even mild cases of COVID-19 may have long term effects. Previous studies have found that the intranasal administration of SARS-CoV-2 in mice resulted in rapid invasion of the brain. Additionally, the reduced ability to taste and smell seem to precede the onset of respiratory symptoms. The virus has also been found in the brain post-mortem, as abnormal brain imaging has become associated with COVID-19.

"The trail of the virus, when it invades the brain, leads almost straight to the hippocampus," said Gabriel De Erausquin, MD, PHD, MSC, a dementia researcher at The University of Texas Health Science Center at San Antonio, in a press release. “That is believed to be one of the sources of the cognitive impairment observed in COVID-19 patients. We suspect it may also be part of the reason why there will be an accelerated cognitive decline over time in susceptible individuals."

REFERENCE:
Journal article reviews century of data showing COVID-19 likely to impact the brain [News Release] January 5, 2021; San Antonio, TX. Accessed January 7, 2021. https://eurekalert.org/pub_releases/2021-01/uoth-jar010521.php.