Active cases of mild COVID-19 last for up to two weeks, with physical symptoms at the height. However, once you have physically beaten the virus, there may be long-term cognitive ramifications you didn't expect. Dr. Rosemarie Booze, a psychology professor at the University of South Carolina, discusses the unexpected 'brain fog' cases among those infected with the coronavirus and her new research on the virus.

The Mysterious Impact of Viruses on the Brain

Dr. Booze is one of the Principal Investigators on three NIH R01s grants to study the neurological and psychological effects of viruses on the brain, particularly the 'long-haul symptoms' that can occur. The Professor and Bicentennial Endowed Chair in Behavioral Neuroscience in the USC Department of Psychology first developed an interest in the subject when her father was diagnosed with Parkinson's disease.

"He has since passed away, but there was some evidence that the influenza virus could cause Parkinson's disease," explains Booze. "I got interested in viral effects on the brain and started studying HIV and, more recently, the COVID effects on the brain."

The impact that viruses — such as influenza, HIV, and COVID — have on the brain is mysterious. Rather than directly impacting the neurons, these infections may have a long-term effect on other, lesser-understood cells within the brain.

"The neurons themselves are not infected," she explains. "But more recently, we've learned that it's actually the supporting cells that are infected. And given that the cells are in the brain, it's been very difficult for the standard treatments to work. Someone could be HIV positive and taking the drugs and a very undetectable viral level in the blood, but the virus is still there in the brain, and that's what's made it a big challenge."

How the COVID-19 Virus Causes' Brain Fog'

When the physiological symptoms of COVID have disappeared, there's a surprising mental side effect that often lingers. 'Brain fog is the term given to a state of confusion and slower cognitive functioning that some people experience after having the virus.

"At least 30% of people have these brain fog cognitive impairments. Why some people are affected and others are not really unclear. It's clear that it does not affect the neurons directly; it's probably affecting the supporting cells in the brain," says Booze.

"The supporting cells have not got as much research as neurons because neurons have been of interest for some time. They're interesting and convey a lot of information, but we're studying how the virus impacts these supporting glial cells."

The jury's still out on how these infected supporting cells impact people's long-term mental functions. However, we can look at some of the early signs of cognitive impairment and its damage to our senses. With that in mind, one of the most intriguing side effects of the virus is a long-lasting loss of smell reported by patients.

"Lots of people with the initial infection report a loss of smell. Obviously, you can't smell when you're all stuffed up. Obviously, you can't smell," says Booze. "But for a virus to have that kind of effect was really unusual. The fact that people showed up reporting that led us to look at the olfactory system more, and see that the cells in the nose were supporting cells, not the neurons, were infected. [It's] so specific to COVID-19."

"Most people do recover their sense of smell, but not everyone. We don't think so much about smell. Humans are very visual," she continues. "Smell is closely related to taste. If you can't smell, your food doesn't taste very good, and so you don't want to eat it. People that lose their sense of smell have a high risk of depression. So, I think one aspect that has come about as a result of COVID is a greater understanding or appreciation of smell."

The Long-Term Effects of COVID-19 on the Brain

Research into the long-haul effects of COVID is well underway. Experts are striving to determine whether the virus could lead to cases of intensified Alzheimer's and other brain-centric conditions. However, it could be a long wait before we have the answers.

"There is no way to know for some time. We can go into the lab and look at our neurons and our dishes, but we'll have to see long term, especially with the long-haul people, how things develop," says Booze. "But with HIV and the successful — so-called successful treatment — that still affects the brain. We're seeing some evidence for accelerated aging there. The brain is very difficult. We don't have very many effective treatments."

While it will take a matter of decades to fully research and understand the cognitive complications that the virus may cause, Rosemarie Booze assures us that researchers are making progress. The revelation that viruses influence supporting cells is a big step forward.

"I think the brain is particularly scary in terms of what could happen in the future, and we don't know yet. So, people would like to be reassured, but the progress on Alzheimer's, Parkinson's, et cetera has been slow," concluded Booze. "We have some clues about these supporting cells and their critical role."

Author's Bio: 

Alex is a professional writer and digital marketing expert.