18 Thursday February 3 2022 | the times
News
Infected people shed a lot of corona-
virus particles even if they have mild
symptoms or no symptoms at all, accor-
ding to a “challenge” trial that deliber-
ately exposed volunteers to the virus.
The study helps to explain the virus’s
ability to spread by looking at the earli-
est stages of infection in a controlled way
for the first time.
“The implication is that a lot ofSufferers with no symptoms
Tom Whipple Science Editor people could be walking around shed-
ding viruses who aren’t yet recognising
that they’re symptomatic,” Professor
Wendy Barclay, of Imperial College
London, said. She added that this high-
lighted the importance of regular test-
ing. “You may think that you’re healthy
and safe to go out and mix with others
but you might not be.”
Scientists have been pushing for the
use of so-called challenge trials since
the start of the pandemic, arguing thatThe Omicron variant has fuelled a
surge of reinfections with more people
catching Covid for a second time in the
past six weeks than in all of the previous
18 months, new figures suggest.
The Office for National Statistics
infection survey, viewed as the best
measure of the state of the epidemic,
has recorded 764 reinfections since
December 20, roughly the point where
Omicron became dominant.
Those cases were from about 28,
survey participants who had tested
positive previously and were therefore
at risk of catching the virus for a second
time. Before the arrival of Omicron, the
infection survey had picked up only 586
reinfections, from among about 25,
people at risk. The estimated rate of
reinfections is now 180 cases per
100,000 people at risk per day. Before
Omicron it was less than 12 cases.
This week the daily case numbers
reported for England by the govern-
ment began counting reinfections;
previously they had been ignored. The
shift in policy reflects the ability of the
heavily mutated Omicron strain to
evade immunity conferred by prior
infections caused by other variants.
The protection against infection that
results from vaccines is also lower for
Omicron, although booster shots are
still highly effective at preventing
severe disease, hospitalisation and
death. People are considered at risk of
reinfection by the ONS if it has been
120 days since their first positive test in
the survey and their most recent test
result was negative, or if they have had
four consecutive negative tests since
their last positive test.
The infection survey aims to swab
nearly 180,000 people across the UK
every fortnight. The latest results
showed that cases remain high. The
ONS estimates that more than 2.6 mil-
Omicron reinfection
rate dwarfs last
18 months of Covid
Rhys Blakely Science Correspondent
Kat Lay Health Editor
lion people in England — or about 1 in
20 — had Covid in the week ending on
January 29. In Wales it was 139,
people, also equivalent to 1 in 20. In
Northern Ireland it was 136,300 people,
or 1 in 15, and in Scotland it was 185,
people, or about 1 in 30. In England
cases were highest in children aged
between two years and school year 6,
with an estimated 1 in 8 infected. Infec-
tion levels looked to be broadly stable in
England and Scotland but were rising
in Wales and Northern Ireland.
The ONS reported earlier this week
that more than 180,000 deaths with
Covid mentioned on the certificate
have now been registered in the UK.
About 9 in 10 deaths with Covid on the
death certificate since the start of the
pandemic have coronavirus as the pri-
mary cause of death, with a minority
listing the virus as a contributory factor.
Figures from the ONS show that
1,484 deaths registered in England and
Wales in the week ending January 21
mentioned Covid on the certificate, up
7 per cent on the week before and the
highest number since the 1,501 deaths
in the week to March 12, 2021.
Separately, Omicron appears to have
called into question the usefulness of
the daily government figures that
count deaths within 28 days of a posi-
tive test. Analysis suggests that because
of high rates of Omicron in circulation,
it is now capturing a higher proportion
of “incidental” Covid deaths — people
in whom the positive Covid result pre-
ceded but did not cause the death.
John Roberts, a member of the
Covid-19 Actuaries Response Group,
wrote on Twitter that the ONS death
certificates measure was now reporting
about 85 per cent of the deaths reported
as within 28 days of a positive test.
“Comparing the 28-day death meas-
ure with the latest ONS data now shows
a clear divergence in recent weeks, even
when the ONS data are adjusted for
typical reporting delays,” he said.The national picture
How does 2021 compare?
There were 13,311 deaths from all causes
recorded in England and Wales in the week
to January 14, of which the coronavirus
accounted for 10.4 per cent. The number
of weekly deaths was 872 lower than the
five-year average for the same time of yearHow many people have Covid-19?
There were 88,085 new cases reported
yesterday, bringing the total to 17,515,
or 262.2 for every 1,000 people
3.5% decrease from seven days ago
(based on seven-day moving average)Oct Jan
2021Apr Jul Oct Jan
2022050,100,150,Daily cases 200,Seven-day
averageNational
R number
0.7 to 1How many are in hospital?
There are 15,233 patients in hospital being
treated. 502 patients are on ventilators. An
additional 1,474 patients have been
admitted, down 11.8 per cent in seven days
to Jan 28 when this data was last updated
Hospital admissionsOct Jan
2021Apr Jul Oct Jan
202201,2,3,4,Seven-day
averageHow many have died?
Yesterday there were 534 deaths reported,
bringing the total number of deaths in the
past seven days to 1,806. The rolling
average number of daily deaths is 258 ,
down from 261.6 a day a week ago
DeathsOct Jan
2021Apr Jul Oct Jan
202205001,Seven-day 1,
averageRestaurant covers Guests at the Hoshinoya Tokyo hotel dine beneath partitionsNews Coronavirus