Most easily infected cells are within the nose, researchers say

The COVID-19 coronavirus probably gains a foothold in the
human body through the nose, according to a recently published study from
researchers at the University of North Carolina at Chapel Hill.
The study led by Richard Boucher and Ralph Baric examined
how easily Sars-CoV-2, the technical name for the virus that causes COVID-19,
affected different types of cells within the human body.
It found that the most easily infected cells are within the
nose. The results also showed that the ease of infection decreases moving down
the respiratory tract, which connects the nose down to the lungs and is the
primary target of the disease.
The virus mainly enters the body through the
Angiotensin-converting enzyme 2 (ACE2), an enzyme which attaches itself to the
outer cells of various organs including the lungs and heart. The mapping
conducted by the North Carolina team found “the highest ACE2 58 expression in
the nose with decreasing expression throughout the lower respiratory tract.”
Much remains unknown
The study will add to the growing body of research attempting
to understand COVID-19, which has killed more than 360,000 people worldwide as
of Saturday.
It can be interpreted as adding to the case for wearing face
masks as a preventative measure against the spread of coronavirus.
However, much remains unknown about the virus.
“The mode of acquisition and causes for the variable
clinical spectrum of COVID54 19 remain unknown,” said the study.
“The sites of SARS-CoV-2 infection in the upper airways
(nose, oropharynx) and 220 lung (lower airways, alveoli) are under active
investigation,” it added.