In new research published in the journal Scientific Reports, researchers from Griffith University revealed that a bacteria can travel from the nose into the brain of mice through the olfactory nerve where it creates markers that can lead to Alzheimer’s disease.

The findings of the study revealed that Chlamydia pneumoniae, a type of bacteria that causes respiratory tract infections, exploited the nerve extending between the nasal cavity and the brain as an invasion path to assault the central nervous system. In response to the invasion, the cells in the brain began depositing amyloid beta protein, which is a hallmark of Alzheimer’s disease.

Professor James St John, Head of the Clem Jones Center for Neurobiology and Stem Cell Research, stated that the olfactory nerve in the nose is directly exposed to air and offers a short pathway to the brain, bypassing the blood-brain barrier. He added that picking the nose or plucking the hairs from the nose is not a good idea as the damage caused by these activities can increase the number of bacteria going into the brain.

He further added that smell tests can be used as a potential detector for Alzheimer’s and dementia as loss of the sense of smell is an early indicator of Alzheimer’s disease, especially for people aged 60 years and older.