The dangerous
asymptomatic
( no symptoms )
COVID-19
infections
allow the
disease
to spread
quickly.
There are
several ways
to stop the
spread,
besides the
social isolation
that forces
a partial
economic
shutdown:
(1)
Mass testing
to isolate only
those people
who are infected.
(2)
A COVID-19
vaccine, which
Bill Gates says
would take
18 months
to develop.
Some experts
say one year
is possible.
Even wishful
thinking would
require six
months!
(3)
Mass antibody
testing, to identify
people unlikely
to get COVID-19
again
An antibody test
is also known as
a serum test .
That test is
NOT yet possible
for COVID-10 with
HIGH accuracy,
although many labs
are getting close.
Tests require
a blood sample,
but will hopefully
show how many
people were
exposed
to the virus.
"Herd immunity"
is when we've had
a large majority
of a population
that had a disease,
and developed
antibodies that
will prevent them
from getting
infected again
( for some
period of time ).
A "large majority"
is considered
to be two-thirds
of the population,
or more.
The unknown
percentage
of COVID-19
infections with
no symptoms
makes us wonder
if herd immunity
is possible.
There have been
two relatively small
antibody studies,
one in Germany,
and one in Austria.
The German study
was not random,
and may have
confused the
antibodies for
coronavirus
common colds,
with COVID-19
antibodies.
We do need
very accurate
antibody tests
to find out
the percentage
of asymptomatic
COVID-19 cases,
previously roughly
estimated here
at 20% to 40%,
but could be
much higher,
or lower.
GERMANY STUDY:
A small study on
the town of Gangelt,
suggested that
15% of the town
might have caught
an asymptomatic form
of COVID-19, because
they had antibodies to it.
But, unfortunately,
the test may have
detected antibodies
to the harmless
common cold forms
of corona virus,
instead of only
the deadly virus:
SARS-Cov-2.
The test was done
just a month after
the end of the
common cold
"season".
One third of common colds
are caused by four known,
harmless corona viruses.
The Braunschweig infection
epidemiologist Gérard Krause,
from the Helmholtz Institute
for Infection Research,
told the Süddeutsche Zeitung
that there are currently
no widely available tests
that could reliably
demonstrate immunity
to Sars-CoV-2.
The town's infections
were started in a cluster
at a large carnival.
That may mean the virus
spread first through a
younger than average
carnival crowd.
That would explain
the rapid spread, and
the low fatality rate.
The researchers
selected households,
not individuals.
Households are
much more likely
to infect each other,
and households
with children
will also be likely
to have more
asymptomatic
COVID-19 cases.
Dr Simon Clarke,
Associate Professor
in Cellular Microbiology,
University of Reading,
said:
“The finding that 14%
of the population of Gangelt
in Germany have antibodies
to the virus causing COVID19
is interesting, but does not
in any way prove that 14%
of the population are immune,
as these reports suggest.
While it’s undeniably
a good sign, merely having
some antibodies does not
necessarily prove immunity,
as is often casually asserted.
We don’t know what
the correlates of protection,
the measurable signs
that someone has immunity
to a disease, are for this virus,
and neither do we know
how long any immunity
would last.
It is important to understand
the sensitivity and specificity
of the serological test used
in the German studies
to be sure the test is not
picking up antibodies
to other corona viruses
(4 different common cold
causing coronaviruses
have been isolated
in humans during
the past years, and
3 more serious ones
( SARSCoV1 and 2,
and MERSCoV )."
AUSTRIA:
Note:
Austria was among
the first of the
European nations
to clamp down
on public life,
and they enforced
social distancing
when cases were
still in the hundreds,
and few had died.
As a result,
their COVID-19
infection rate
should be
unusually low.
Austria will soon be
allowing small shops
and hardware and
gardening stores
to reopen,
but will keep schools,
and other stores,
closed until May.
In a small random
study in Austria,
only 0.33% tested
were infected
about a week
after the nation's
COVID-19 peak.
The co-founder of Sora,
Christoph Hofinger,
told a news conference:
“Based on this study,
we believe that 0.33%
of the population in Austria
was acutely infected
in early April.”
"Given the margin of error,
the figure was 95% likely
to be between 0.12%
and 0.76%."
They also estimated
that 75% of infections
had mild symptoms,
or no symptoms.
Austrian chancellor,
Sebastian Kurz,
rounded up,
and said that the
rate of infection
was about 1%.
In plain English,
that means
at least 99% of the
Austria population
is still vulnerable
to COVID-19.
Whether 0.3%
or 1% ( or 10% ),
the percentage
is far too low
for a "herd
immunity".
Herd immunity
requires
widespread
COVID-19
infections,
and antibodies.