How relaxing COVID-19 restrictions could pave the way for vaccine
resistance

Date:
July 27, 2021
Source:
University of East Anglia
Summary:
A new article outlines how relaxing Covid-19 restrictions could pave
the way for new vaccine-resistant virus mutations. It describes how
we are in an 'arms race' with the virus and how rising cases could
provide opportunities for it to evolve into even more transmissible
variants. The researchers say that any new variants could be more
virulent, more vaccine resistant, and more dangerous for children
and vulnerable groups such as transplant patients.



FULL STORY ========================================================================== Relaxing Covid-19 restrictions could pave the way for new
vaccine-resistant virus mutations, according to researchers at the
University of East Anglia and the Earlham Institute.


==========================================================================
A new article published today warns against relaxing Covid-19 restrictions prematurely.

It describes how we are in an 'arms race' with the virus and how rising
cases could provide opportunities for it to evolve into even more
transmissible variants.

The researchers fear that any new variants could be more virulent, more
vaccine resistant, and more dangerous for children and vulnerable groups
such as transplant patients.

Lead author and editor in chief of Virulence, Prof Kevin Tyler from
UEA's Norwich Medical School, said: "Over the past 17 months, economies, education and mental well-being have suffered tremendously due to the restrictions imposed in an attempt to stem the spread of the pandemic.

"Although vaccines have weakened the link between infection and mortality,
they should not be used as an argument to justify a broad change in policy
for countries experiencing an exponential increase in infection numbers.



========================================================================== "This is because most of the world's population are still unvaccinated,
and even in countries with efficient vaccination programmes, a significant proportion of society, particularly children, remain unprotected.

"Relaxing restrictions boosts transmission and allows the virus population
to expand, which enhances its adaptive evolutionary potential and
increases the risk of vaccine-resistant strains emerging by a process
known as antigenic drift.

"Put simply, limiting the spread of Covid-19 as much as possible restricts
the number of future deaths by restricting the rate with which new
variants arise.

"Successive SARS-CoV-2 variants such as the Alpha and Delta variants,
have displaced one another since the outbreak.

"Slowing down the rate of new variant emergence requires us to act fast
and decisively, reducing the number of infected people including children
with vaccines and in combination with other public health policies.



==========================================================================
"In most cases, children are not vaccinated against Covid-19 because
the risk to them becoming seriously ill is very low. But new strains
may evolve with higher transmissibility in children, and vaccinating
children may become necessary to control the emergence of new variants.

"In other words, a policy of relaxing restrictions while children are
not vaccinated, risks inadvertently selecting for virulent variants
that are better able to infect children and are also more problematic
in vulnerable groups.

"Children may be particularly at risk because they are the only group
that has remained unvaccinated. But there is no guarantee that the virus
won't evolve the ability to infect children too, and the data shows that
new variants are relatively more often found in younger age groups.

"Only when a large proportion of the world's population is vaccinated, or
has acquired immunity from infection, can we relax other social measures.

Co-lead author and evolutionary biologist Prof Cock Van Oosterhout, from
UEA's School of Environmental Sciences, said: "We have an arms race on
our hands.

"On the human side, the arms race is fought with vaccines, new technology
such as the NHS Covid-19 App, and our behavioural change, but the virus
fights back by adapting and evolving.

"It is unlikely we will get ahead in this arms race unless we can
significantly reduce the population size of the virus.

"But given that the infection rate is about the same now as it was during
the first wave, we are pretty much 'at evens' with this virus.

And as with many other coevolutionary arms races, there are no winners.

"This is what evolutionary biologists mean when we say that coevolution
is a 'zero-sum game'. But what you cannot do is suddenly drop your guard
in the middle of an arms race. That gives your opponent -- the virus --
a real advantage. So we must continue doing the things we have been doing
for the past 18 months, particularly in countries where the number of
infected people is increasing.

"Entrusting public health measures to personal responsibility is a
laissez- faire approach that many governments are now taking towards
Covid-19 management.

"During exponential transmission of virus, we need an ongoing, mandatory
public health policy that includes social distancing and the compulsory
wearing of facemasks in crowded indoor spaces such as shops and on
public transport.

"Our current vaccination programmes alone will not end the pandemic
and scientific evidence suggests that we can only safely start to relax
social restrictions when the R number is below one," he added.

Co-author and director of the Earlham Institute (EI), Prof Neil Hall,
said: "As long as there are large numbers of unvaccinated people around
the world transmitting the virus, we're all at risk.

"High numbers of Covid-19 cases increase the likelihood the virus
will evolve to become more virulent, more transmissible, or capable of
evading vaccines.

It's critical we continue using public health measures to bring
transmission rates down. We have to co-exist with caution -- if we
ignore global health policies which have proven to reduce infection,
the virus will further adapt.

"When we weigh up the benefits and risks in vaccinating young people,
we have to consider the impact on wider society too. The current approach
to protecting young people seems to be letting them reach herd immunity
through infection.

Every day that approach continues, we give the virus the upper hand and
prolong this pandemic -- increasing the burden on healthcare systems
and economies." 'COVID-19 adaptive evolution during the pandemic -- Implications of new SARS- CoV-2 variants on public health policies'
is published in the journal Virulence on July 27, 2021.

The article was led by researchers at UEA in collaboration with Norwich Research Park colleagues at the Earlham Institute, as well as it the
University of Pittsburgh, the University of California Davis, the
University of Minnesota Twin Cities, and King Abdul Aziz University,
Jeddah, Saudi Arabia.

========================================================================== Story Source: Materials provided by University_of_East_Anglia. Note:
Content may be edited for style and length.


========================================================================== Journal Reference:
1. Cock van Oosterhout, Neil Hall, Hinh Ly, Kevin M. Tyler. COVID-19
evolution during the pandemic - Implications of new SARS-CoV-2
variants on disease control and public health policies. Virulence,
2021; 12 (1): 507 DOI: 10.1080/21505594.2021.1877066 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2021/07/210727195333.htm

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