Status of Omicron Variant of COVID
As of January 18,
2022
By Ken Karch, PE, MPH
(New material (since 1/8/22) in yellow)
The COVID-19 Omicron
variant is much more transmissible than any of the earlier variants.
This is both good
news and bad news.
Bad News
The bad news
is that Omicron spreads very rapidly, giving little time to develop
prevention and treatment strategies…if it were as deadly as the plague,
cholera, typhoid, or smallpox (in their day) or MERS more recently, it would be
a human calamity, given the ease of spread around the world. The R value for Omicron (a measure of transmissibility)
was recently about 2.5 in South Africa (the most advanced nation in terms of
disease stages), as opposed to about 1 for Delta. Of all new COVID cases, in South Africa, virtually
100% are Omicron, with Delta having shrunk to near zero. In the UK it is over 95%
and in the US over 90%. The Omicron
variant has displaced the Delta variant in all three regions.
The R factor
of about 2.5 means the rate of new recorded cases is doubling about every 2-3
days, indicating the entire population of the UK (a second exemplar) will
likely be virtually totally exposed within a week, and the US during January.
It is important to remember that exposure does not equal
infection. Infection will result in no clinical symptoms in most, mild symptoms
in some cases, and severe enough cases to result in hospitalization in a small
percentage of those infected. The latter will result in the need for ICU
treatment, including intubation, oxygen, or monoclonal antibody treatment in a
small fraction of those hospitalized.
This is
likely to lead to many, horrific, ill-founded, and contradictory actions by poorly-informed
elected officials and private organizations.
Omicron also appears
to be much more transmissible, and with more severe consequences, for young
people, than did Delta, whose consequences were largely centered on older
adults with immune system problems and health care workers.
Good News
The good news
is that the Omicron variant is apparently much less deadly and results in
much less hospitalization than any of the previous variants, including the
Delta variant…perhaps by a factor of 10 (as against the Delta variant). Normalized hospital admission and death rates
are far below those for Delta, and both are much reduced from just 2 months ago.
COVID hospital admissions in Washington State have risen to levels which have
again created capacity concerns comparable to those experienced in the August/September,
2021 period, before declining. Recent reports indicate that “incidental” Omicron
variant hospital admission rates are in the 50-65% range in New York hospitals,
indicating that 50-65% of the admissions are for causes other than Omicron,
with hypertension, diabetes, and obesity leading the co-morbidity list Both hospital
admissions and deaths will likely show increases, due largely to the greatly
increased number of people exposed, (to Omicron) with new cases, hospitalizations,
and death peaking in the late-February to mid-March, 2022 period. Treatment
modalities developed for earlier COVID variants seem to work for Omicron, greatly
reducing the need for hospitalization, supplemental oxygen, or intubation;
and a growing body of studies is identifying alternative prevention and
treatment techniques.
Other pieces
of good news include reports that past Delta or Omicron infections and
vaccinations seem to confer some degree of protection from serious complications
from either, the need for hospitalization, and death; that vaccines are capable
of being much more rapidly developed; and that the rapid rate of Omicron infection
is likely to attain a degree of herd immunity not yet reached for Delta.
New News
Data from
South Africa suggests T- and B-cell behavior is moderating the seriousness
of the Omicron variant, and preventing further Delta infection. In an as
yet non-peer reviewed paper released last week, antibodies developed from prior
vaccinations or Delta infections do not confer immunity from the Omicron
variant, allowing it to spread rapidly and out-compete, and therefore replace,
the Delta variant. In another paper, a possible mechanism, through a jump from
humans to mice and back again, very early in the history of COVID-19, is
described.
Finally, the US Supreme Court on January 13 ruled
in two cases involving the authority for administrative agency mandatory
vaccination orders for all employers of more than 100 employees (overturned),
and for health care organizations (allowed to proceed). Hearings and decisions are
likely to be heard and reached on a third issue (and probably several others
which have not yet reached the Supreme Court) the next few weeks or months.
Bottom Line
Cautious
optimism that Omicron may out-compete and replace Delta as the dominant COVID variant in
Washington State, the US, and the world, with vaccination, previous
infections, and rapid attainment of herd immunity ending the COVID crisis,
and reducing it to endemic proportions, such as the common cold, another COVID
variant.
Recommendations
Continue
social distancing, masks, and full vaccination encouragement. Increase focus on
young peoples’ exposure, prevention, and treatment. Relax non-traditional prevention and
treatment protocols.
