Coronavirus disease (COVID-19) is an infectious disease caused by the SARS-CoV-2 virus. While the disease is relatively new, researchers are now studying its long-term effects. Some people with COVID-19 experience little to no symptoms, while others continue to experience fatigue, respiratory and neurological symptoms.

According to a recent report, eighty percent of individuals hospitalized for COVID-19 reported neurological symptoms. Because of this, researchers from the California National Primate Research Center at the University of California, Davis, decided to explore this complex issue further. The findings reveal significant neuron damage and inflammation in rhesus macaque monkeys within a week of infection.

In addition, the study unveiled an exacerbated effect in older rhesus macaques and those with Type 2 diabetes. The virus spread further in the brain, by traveling through the nose along the olfactory nerve, in aged animals and affected their memory and cognition causing particular concerns about potential spikes in neurodegenerative diseases in humans.

John Morrison, professor of neurology at UC Davis and director of the CNPRC, states, “In the aged monkeys, in particular, the virus is infecting neurons in regions known to be highly vulnerable to Alzheimer’s disease.” 

The researchers plan to continue to study the brain post-infection to examine the extent and nature of brain damage underlying the long-term neurological complications of COVID-19 to help doctors better understand how to help humans affected by the disease.