“Although scientists are still learning how the SARS-CoV-2 virus is able to invade the brain and central nervous system, the fact that it’s getting in there is clear,” Kevin J. Barnham, PhD, a neuroscientist from the Florey Institute of Neuroscience & Mental Health in Australia and one of the paper’s co-authors, said in a statement on the Florey Institute’s website. “Our best understanding is that the virus can cause insult to brain cells, with potential for neurodegeneration to follow on from there.” Of the many symptoms that COVID-19 has been reported to cause, one of the most common, and seemingly innocuous, among them may in fact be the biggest indicator of a link between the virus and Parkinson’s. “We found that loss of smell or reduced smell was on average reported in three out of four people infected with the SARS-CoV-2 virus,” Leah Beaucamp, PhD, Florey research and co-author of the paper, said in the same statement from the institute. “While on the surface this symptom can appear as little cause for concern, it actually tells us a lot about what’s happening on the inside and that is that there’s acute inflammation in the olfactory system responsible for smell.” She added that loss of smell is found in the early stages of Parkinson’s in about 90 percent of cases.ae0fcc31ae342fd3a1346ebb1f342fcb The researchers point to the Spanish Flu outbreak in 1918 as potential evidence that a virus can raise a person’s risk of developing Parkinson’s disease. According to the paper, some scientists say that 1918 flu caused more severe cases of encephalitis lethargica—a mysterious brain disease during that the time that has since disappeared, but was believed to cause severe Parkinson’s symptoms. “We can take insight from the neurological consequences that followed the Spanish Flu pandemic in 1918 where the risk of developing Parkinson’s disease increased two to three-fold,” Barnham said. “Given that the world’s population has been hit again by a viral pandemic, it is very worrying indeed to consider the potential global increase of neurological diseases that could unfold down track.” RELATED: For more up-to-date information, sign up for our daily newsletter. And while there is insufficient evidence to support that COVID-19 will result in a spike in the number of individuals with Parkinson’s disease, Florey researchers believe there is enough to make the hypothesis. If nothing else, they believe the medical community needs to be willing to change how it thinks about Parkinson’s disease from a general perspective. “We have to shift community thinking that Parkinson’s is not a disease of old age. As we’ve been hearing time and time again, the coronavirus does not discriminate—and neither does Parkinson’s,” said Barnham. And for more on the coronavirus, check out This Hard-Hit State Has By Far the Worst COVID Outbreak in the Country.