OPINION
GUEST ESSAY
3 Questions We Must Answer About the Omicron
Variant
Nov. 27,
2021
By Ashish
Jha
Dr. Jha is
the dean of the Brown University School of Public Health.
https://www.nytimes.com/2021/11/27/opinion/omicron-variant-questions-coronavirus.html
Every few
months, the world learns of a new variant of the coronavirus. While most of
these variants turn out to be inconsequential, some, like the Delta variant,
are immensely consequential. The latest, B.1.1.529, now known as the Omicron
variant, bears very close watching because of concerns that it may spread more
quickly than Delta, possibly even among the vaccinated. It is essential that
world leaders respond quickly and aggressively even before all the data about
this variant emerge.
In the days
ahead, as information builds, it will be tempting to give in to fear or
indifference. We cannot succumb to either. The global community must take each
variant seriously. Acting early is far superior to waiting until all the facts
are in. It may turn out that the variant is not more contagious or that it
responds perfectly well to our current vaccines. In that latter fortuitous
scenario, the current response may be seen as an overreaction. But if this
variant, with all of its concerning features, turns out to be as contagious and
immune-evasive as many experts worry it might be, waiting until all the facts
are in will leave us hopelessly far behind.
How
worrisome is Omicron? There are three key questions that help scientists
understand how consequential any variant might be.
The first
question is whether the variant is more transmissible than the current,
prevalent Delta strain? Second, does it cause more severe disease? And third,
will it render our immune defenses — from vaccines and prior infections — less
effective (a phenomenon known as immune escape)?
On
transmissibility, the data, while early, look worrisome. This new variant
appears to have taken off very quickly in South Africa, with early national
data suggesting the variant already makes up the majority of sequenced cases in
the country. It’s possible that this early data will be revised as
epidemiologists look closer at factors other than transmissibility, such as
whether an early Omicron superspreader event led to the variant appearing more
highly contagious than it really is. While this is possible, the more likely
scenario is that Omicron does spread more easily than Delta.
Because the
variant is so new, scientists simply do not have adequate data yet to assess
whether the new variant causes more severe disease. Answering this question
will require careful case tracking in hospitals along with expanded viral
sequencing efforts, both in South Africa and elsewhere. A key part of this
analysis is ensuring that countries are doing adequate testing of a broad
sample of people. It will likely take weeks to sort this out.
Finally,
the big concern with Omicron is immune escape. Let’s be clear: It is extremely
unlikely that Omicron will render the Covid-19 vaccines completely ineffective.
And right now, there’s not much data on how much the vaccines may be less
effective against this variant, although there is reason for concern. Omicron
has a large number of mutations, including in the spike protein — the part of
the protein that the virus uses to bind to and enter human cells. These areas
of the protein are critical for vaccine-induced (and infection-induced)
antibodies to protect against the virus. Even small hits to vaccine efficacy
will leave us more vulnerable to infection and illness and can make it harder
to contain the virus.
The Biden
administration just announced a travel ban against foreign nationals coming
from eight African countries. This will slow the spread of the virus into the
United States by a modest amount at best. And it sends a negative signal to
South Africa, which has done an extraordinary job in first identifying the
variant and then quickly sharing the information with the global community.
Whether the travel ban will be worth it or not is far from clear.
But there
are things the Biden administration can do to prepare the country.
The United
States must support ongoing studies that help researchers answer the key
questions about how transmissible the variant is, whether it causes more severe
disease and whether it can evade immunity. This will give health authorities a
more complete picture as quickly as possible.
Second, the
United States must ramp up genomic surveillance — monitoring viral genes and
how they evolve over time — to identify Omicron when it arrives and track it as
it potentially spreads through the country. The United States has been a
surprising laggard on genomic sequencing and must do better.
American
leaders should also start talking with vaccine makers about the potential need
to create Omicron-specific vaccines. It may not be needed, but if there is a
large hit to vaccine efficacy then new vaccine shots will be critical.
Lastly,
America must push for a global effort to get more people in Africa vaccinated.
While global vaccinations have been rising quickly, much of the African
continent has been left behind. In South Africa, just under a quarter of the
population has been fully vaccinated.
It has been
a long pandemic thus far, but let’s remember that this is not a reset to March
of last year — the world has the means to manage this variant. Let’s use them.
Dr. Ashish
K. Jha is dean of the Brown University School of Public Health.
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