We Must Start
Planning For a Permanent Pandemic
With coronavirus mutations pitted against vaccinations in a
global arms race, we may never go back to normal.
By Andreas Kluth
March 24, 2021, 1:30 AM EDT
For the past year, an assumption — sometimes explicit, often
tacit — has informed almost all our thinking about the pandemic: At some point,
it will be over, and then we’ll go “back to normal.”
This premise is almost certainly wrong. SARS-CoV-2, protean
and elusive as it is, may become our permanent enemy, like the flu but worse.
And even if it peters out eventually, our lives and routines will by then have
changed irreversibly. Going “back” won’t be an option; the only way is forward.
But to what exactly?
Most epidemics disappear once populations achieve herd
immunity and the pathogen has too few vulnerable bodies available as hosts for
its self-propagation. This herd protection comes about through the combination
of natural immunity in people who’ve recovered from infection and vaccination
of the remaining population.
In the case of SARS-CoV-2, however, recent developments suggest that we may never achieve herd immunity.
Even the U.S., which leads most other countries in vaccinations and already had
large outbreaks, won’t get there. That’s the upshot of an analysis by
Christopher Murray at the University of Washington and Peter Piot at the London
School of Hygiene and Tropical Medicine.
The main reason is the ongoing
emergence of new variants that behave almost like new viruses. A
clinical vaccine trial in South Africa showed that people in the placebo group
who had previously been infected with one strain had no immunity against its
mutated descendant and became reinfected. There are similar reports from parts
of Brazil that had massive outbreaks and subsequently suffered renewed
epidemics.
That leaves only
vaccination as a path toward lasting herd immunity. And admittedly, some
of the shots available today are still somewhat effective against some of the
new variants. But over time they will become powerless against the coming
mutations.
Of course, vaccine makers are already feverishly working on
making new jabs. In particular, inoculations based on the revolutionary mRNA technology I’ve previously described can be updated faster than any vaccine
in history. But the serum still needs to be made, shipped, distributed and
jabbed.
And that process can’t happen fast enough, nor cover the
planet widely enough. Yes, some of us may win a regional round or two against
the virus, by vaccinating one particular population — as Israel has done, for
instance. But evolution doesn’t care where it does its work, and the virus
replicates wherever it finds warm and unvaccinated bodies with cells that let
it reproduce its RNA. As it copies itself, it makes occasional coding mistakes.
And some of those chance errors turn into yet more mutations.
These viral avatars are popping up wherever there’s a lot of
transmission going on and somebody bothers to look closely. A British, a South
African and at least one Brazilian strain have already become notorious, but
I’ve also seen reports of viral cousins and nephews showing up in California,
Oregon and elsewhere. If we were to sequence samples in more places, we’d
probably find even more relatives.
We should therefore assume that the virus is already
mutating fast in the many poor countries that have so far received no jabs at
all, even if their youthful populations keep mortality manageable and
thus mask the severity of local outbreaks. Last month, Antonio Guterres,
the Secretary General of the United Nations, reminded the world that 75% of all
shots had been administered in just 10 countries, while 130 others hadn’t
primed a single syringe.
A pathogen’s evolution is neither surprising nor
automatically worrisome. One frequent pattern is that bugs over time become
more contagious but less virulent. After all, not killing your host too
efficiently confers an advantage in natural selection. If SARS-CoV-2 goes this
route, it’ll eventually become just another common cold.
But that’s not what it’s been doing recently. The variants
we know of have become more infectious, but no less lethal. From an
epidemiological point of view, that’s the worst news.
Consider two alternative evolutionary paths. In one, a virus
becomes more severe but not more transmissible. It will cause more disease and
death, but the growth is linear. In the other path, a mutating virus becomes
neither more nor less virulent but more contagious. It will cause increases in
disease and death that are exponential rather than linear. Adam Kucharski at
the London School of Hygiene and Tropical Medicine explains the math here.
If this is the evolutionary trajectory of SARS-CoV-2, we’re
in for seemingly endless cycles of outbreaks and remissions, social
restrictions and relaxations, lockdowns and reopenings. At least in rich
countries, we will probably get vaccinated
a couple of times a year, against the latest variant in circulation, but
never fast or comprehensively enough to achieve herd immunity.
I’m not arguing for defeatism here. In the grand sweep of
history, Covid-19 is still a relatively mild pandemic. Smallpox killed nine out
of 10 Native Americans after the Spanish brought it to the Americas in the 16th
century. The Black Death carried off about half of the Mediterranean population
when it first came to Europe in the sixth century. Worldwide, the coronavirus
has killed fewer than four in 10,000 so far. And with our science and
technology, we’re armed as our ancestors never were.
But we must also be realistic. Resilience demands that we
include this new scenario into our planning. The good news is that we keep
getting better at responding. In each lockdown, for example, we damage the
economy less than in the previous one. And we may achieve scientific
breakthroughs that will eventually make life better. Our Brave New World
needn’t be dystopian. But it won’t look anything like the old world.
This column does not necessarily reflect the opinion of the
editorial board or Bloomberg LP and its owners.
To contact the author of this story:
Andreas Kluth at akluth1@bloomberg.net
To contact the editor responsible for this story:
James Boxell at jboxell@bloomberg.net
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