2021-01-30_New_Scientist

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30 January 2021 | New Scientist | 11

IT APPEARS that the new coronavirus
variant first identified in the UK is
slightly deadlier as well as more
transmissible than older variants.
But thanks to improved treatments,
the risk that people who are infected
will die could still be lower in the UK
than it was during the first wave
of the pandemic last March.
“The additional mortality from
the new variant is concerning,” says
Graham Medley at the London School
of Hygiene & Tropical Medicine
(LSHTM). But the main reason why so
many people are dying now in the UK
is the number of infections, he says.
“If you want to reduce the number
of deaths, you have to reduce the
incidence. That is the critical thing.”
There is now strong evidence
that the B.1.1.7 variant is around
50 per cent more transmissible
than previous variants.
Determining whether any variant
is deadlier than another is much
harder, given that there are far fewer
coronavirus-related deaths than
infections. It remains unclear whether
the P.1 variant in Brazil and the
B.1.351 variant from South Africa
are any deadlier than previous
variants. South Africa has reported


40 to 80 per cent higher mortality
in the hardest-hit regions compared
with its first wave, but attributes
this to increasing pressure on the
healthcare system.
To find out if B.1.1.7 is deadlier,
researchers looked at what
happened to around a million
people who tested positive for the
coronavirus in the UK. Of these,
around 100,000 were very likely
to have had B.1.1.7, based on tests.

The researchers compared people
infected with B.1.1.7 to matched
controls who had other variants. In
addition to matching people’s age,
sex and ethnicity, the researchers also
attempted to account for the fact that
hospitals in some areas were busier
than others and might not have been
able to provide the same level of care.
Four independent teams have now
analysed this data, in various ways.
All concluded that people infected
with B.1.1.7 have a higher risk of
dying, with two teams finding a rise
of about 30 per cent, one a 65 per
cent rise and one a 90 per cent rise.

“Any way that you do it, you get
an estimate that is very similar,” says
John Edmunds, also at the LSHTM.
Although these estimates may not
seem that similar, a coronavirus
variant could theoretically be 500
or even 5000 per cent deadlier.
A more transmissible virus is
worse than a deadlier virus, says
Edmunds. “Unfortunately, it appears
this [variant] might be both.”
While this sounds alarming, the
overall risk of dying if infected remains
low. For instance, during the first
wave, the infection fatality rate was
around 1 in 100 in high-income
countries. It is thought to have fallen
significantly since. “Treatments have
been improving,” says Peter Horby
at the University of Oxford, who
chairs the UK’s New and Emerging
Respiratory Virus Threats Advisory
Group. “That may well offset any
differences in this new variant.”
For people who have had at
least one dose of a vaccine, the
risk of dying will be even lower still.
So these findings are no cause for
panic, but they are a reminder of how
important it is that we all redouble
our efforts to avoid becoming
infected and infecting others. ❚

Paramedics unload
equipment at the
Royal London Hospital

“ We are optimistic that it
can be a really effective
way to provide surveillance
for large populations”

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Variant detection


Virus variants found


in sewage before


tests reveal them


VARIANTS of coronavirus can be
detected in wastewater long before
they are spotted by tests in people.
Those infected with coronavirus
shed it in their faeces. Hundreds
of municipalities around the world
already test wastewater for the
presence of the virus as part
of their surveillance operations.
Now research suggests they
could also check which genetic
variants are circulating to flag up


potentially dangerous new versions.
Kara Nelson at the University
of California, Berkeley, and her
colleagues recently extracted useful
sequence information from San
Francisco’s sewage. Another team,
led by Niko Beerenwinkel at ETH
Zurich, detected the genome of the
B.1.1.7 coronavirus variant – first
seen in the UK – in Swiss sewage
sampled in mid-December, two
weeks before the first confirmed
case of the variant in Switzerland.
“We’ve demonstrated it can work
and are now trying to apply it at
larger scales,” says Nelson. Working
with the California Department of

Public Health, her team hopes to
have a wastewater sequencing
system running in four weeks.
The virus is diluted in wastewater
but is detectable if more than 1 in
1000 people are shedding it, says
Sharon Peacock at the COVID-
Genomics UK Consortium. That is
a relatively low infection rate: parts
of the UK have recently seen rates of
about 1 in 30. The UK does sewage
surveillance for coronavirus and is

working on adding sequencing
capabilities to it, says Peacock.
Wastewater monitoring has
the added advantage of sampling
everyone who uses the sewage
system, not just those who turn up
for a test or treatment. That includes
asymptomatic carriers who may
be spreading new mutants.
“We are very optimistic that it can
be a really efficient and effective
way to provide surveillance for
large populations,” says Nelson.
It could be very useful in low-income
countries that don’t have the
capacity or funds for mass testing. ❚
Graham Lawton

Analysis Viral spread


Is the new UK variant more deadly as well as spreading faster?


Evidence is mounting that the variant first detected in the UK is more


lethal, but there is no need to panic, reports Michael Le Page

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