We all know that when people with
coronavirus
sneeze or cough on you you're at risk of
getting it. But even when we speak or
sing or shout
particles come out of our noses and
mouths. Big bits of spittle can come
flying out when you're shouting
and smaller droplets and air sliced bits
can also
come out in clouds that may linger in
the air. In some settings,
especially crowded indoor rooms where
many people are gathering, there's the
possibility that clouds of the virus
expelled when someone speaks
might be able to stay aloft in the air
and potentially infect people further
than the recommended six feet of social
distance.
What's the evidence you ask? Well there
was that time in late January when
ten people were infected in a windowless
restaurant in Guangzhou, China.
More than 80 people had shared the
dining room that day, but the ten that
got sick
were all sitting in the path of one air
conditioning event
that may have sucked in viral particles
from someone in the room later confirmed
to have it.
Another classic example scientists bring
up is a choir practice back in March in
Washington state.
Fifty-three out of 61 people who attended came
down with COVID-19.
The act of singing where you're
breathing deeply and projecting your
voice
spews tiny virus particles from deep
inside the lungs that can then stay
aloft in the air.
Researchers look at these examples and
say well it's possible
especially in crowded indoor rooms with
not so great ventilation
that the virus can build up in the air
and travel on air currents spreading to
others.
What's still unclear is how long the
virus lingers in the air, how far it
travels through a room,
how much you need to breathe in to get
infected, and how commonly it spreads
this way.
But scientists at the World Health
Organization say airborne transmission
cannot be ruled out.
So what can you do to protect yourself?
Well it seems like airflow has something
to do with it. So researchers recommend
making the indoors more like the outside.
What they mean by that is to open the
windows and put some fans in them to pull outside air in.
That fresh air will scatter the clouds
of virus that might exist
and that way you're less likely to
breathe in a big infectious dose of the
virus.
They also recommend cleaning indoor air
perhaps by using an air purifier.
You might consider doing what Seema Lakdawala,
a flu researcher at the
University of Pittsburgh, does.
When she encounters someone she tries
not to talk to them straight-on,
face-to-face, in person. "Right so what i
do is:
when i'm walking and I can't have six
feet of distance between me and someone
else, I tend to turn my head
so that I am not directly face -to-face
with somebody that I'm
breathing in their entire plume of air.
Some of this might be common knowledge
by now,
but make sure that you wear your mask
right and also keep a personal space
bubble of six feet between you and other
people.
The mask will catch a lot of the
droplets that come out when you speak or
laugh or cough
and also block some of other people's
droplets from getting into your nose and
mouth.
And that six feet of space between you
and others means there's more air
passing between you
to dilute any clouds of virus that might
be expelled.
The last tip is to limit the amount of
time you spend indoors with other people.
The more time you spend, especially
indoors, talking to someone who's
infectious or breathing in a lingering
virus cloud,
the more likely you are to get infected.
So yeah,
experts don't recommend that you spend a
lot of time at the grocery store picking
out the perfect peach or that you drink
the night away at a bar.
By keeping yourself moving and the air
around you moving, you'll minimize your
chances of downing a big infectious
whiff of the virus.
For NPR I'm Pien Huang. I'm a global
health and development reporter for the
science desk.
