It’s believed that humans have 14 types of noses. But whatever the type you have, the vital organ of your face is a gateway for virus linked to brain disorders, scientists have claimed.
Researchers in the US found that the nose can be a portal for herpes virus-6 (HHV-6), a member of herpes viruses family, which is linked to brain disorders such as multiple sclerosis, encephalitis and a form of epilepsy.
It also causes roseola, a disease common among infants that leads to high fever and skin rash, LiveScience reported.
“This is a virus that we’ve all been exposed to, that we all pretty much acquired in childhood,” said researcher Steven Jacobson, a neurovirologist at the National Institute of Neurological Disorders and Stroke in Bethesda, Maryland.
“Most of the time it’s utterly benign.”
The way this virus entered the brain had remained a mystery, as the seat of our intelligence is largely protected by the so-called blood-brain barrier, which filters out many germs and drugs.
However, researchers had known that other viruses, such as influenza and rabies, apparently could use the sensory network hooked up to the nose as a kind of highway into the central nervous system.
To see how HHV-6 enters the brain, scientists analysed tissue samples from autopsies, including a patient who had multiple sclerosis. Although viral DNA was seen throughout the brain, it was found largely in the olfactory bulb, the brain region involved in detecting odours.
In addition, the researchers found DNA from HHV-6 in nasal mucus samples from healthy people, those suffering a loss of smell, and people with multiple sclerosis.