By Jason Douglas and Max Colchester
LONDON -- The U.K.'s rapid vaccine rollout contributed to a
substantial drop in infections, hospitalizations and deaths from
Covid-19, according to data that add to a growing body of evidence
that the shots provide significant protection against the
disease.
The new information from the U.K., published Monday, is
preliminary and hasn't been reviewed by other scientists, but
provides reasons for optimism that vaccines offer a route out of a
pandemic that has claimed at least 2.5 million lives world-wide and
sickened tens of millions.
The data suggest vaccines are most successful in preventing
hospitalizations and deaths, a top concern of health authorities.
While vaccines also suppress new infections, the effect isn't as
pronounced.
The information appears to vindicate the U.K.'s policy of
stretching limited vaccine supplies by delaying a second shot to up
to 12 weeks after the first, while also emphasizing the extra
protection that comes from a second shot.
The data include an analysis of the effect of vaccinations among
the elderly, a study looking at infection among vaccinated and
unvaccinated healthcare workers, and a broad look at vaccinations
in Scotland that covered more than five million people.
England's public-health agency said that one shot of the vaccine
developed by Pfizer Inc. and BioNTech SE led to a 57% reduction in
cases of Covid-19 in people age 80 or over, compared with what
would have been expected had they not received a shot. That figure
includes mild cases. Analysis suggests the reduction in severe
cases after one dose is around 75%, said Chris Whitty, England's
chief medical officer.
The level of protection against any form of disease rose to 88%
after a second dose, the data show. The U.K. has chosen to extend
the interval between doses to get first doses to more people,
boosting the number of people with some degree of protection. The
data show the second dose is important, said David Strain, a
physician and instructor at the University of Exeter's medical
school who also treats Covid-19 patients.
A separate analysis of healthcare workers showed the Pfizer
vaccine reduced Covid-19 infections by 72% three weeks after one
dose, rising to 86% after a second shot.
The apparent protection offered is lower than suggested in the
unusual conditions of clinical trials, an outcome scientists
expected in a real-world rollout. Similarly, scientists said it
isn't a surprise that protection appears lower in the very old, a
phenomenon seen with other vaccinations.
Researchers in Scotland earlier Monday published a preliminary
analysis of 5.4 million health records showing similar results.
They found that hospitalizations with Covid-19 were 85% lower among
those receiving a single dose of Pfizer's shot a month after
injection, compared with those who didn't get vaccinated. A single
dose of the shot from AstraZeneca PLC led to a 94% reduction in
hospitalizations.
The data were published on the day the U.K. government outlined
a plan for England to slowly emerge from a lockdown in place since
Jan. 4. It will start with reopening schools on March 8. The
government aims to remove most social-distancing restrictions by
June 21 at the earliest. All Britons are due to be offered
vaccinations by the end of July. Around a third of the U.K.
population has already received one dose of a Covid-19 vaccine.
The data from the vaccine rollout in the U.K. doesn't answer the
question of whether the vaccines cut transmission of the disease,
an issue as governments prepare to roll back strict public-health
restrictions on their economies.
Scientists also cautioned that it was too early to say how long
protection conferred by the vaccine will last. Another uncertainty
is whether a mutation in the coronavirus will render current
vaccines ineffective.
The U.K. data paint a similar picture to preliminary real-world
data from Israel. A study published Feb. 14 by Clalit, Israel's
largest healthcare provider, recorded 94% fewer symptomatic
Covid-19 infections among 600,000 people who received two doses of
Pfizer and BioNTech's vaccine compared with an unvaccinated group
the same size. The vaccinated group was also 92% less likely to
develop severe illness from the disease.
No major Western nation has approved or rolled out vaccines as
fast as the U.K. The country started distributing the Pfizer
vaccine in December to people over 80 and healthcare workers.
Britain is on track to offer vaccines to all people 50 and older by
the end of April.
Despite the largely positive findings, the U.K. is still under
lockdown and several months away from fully reopening, a reminder
that even with a fast-track vaccination program it can take time
for life to return to normal.
Though the data show vaccine effectiveness below the 95% shown
in the Pfizer trials, government scientists were upbeat about the
findings. In the U.K. the group who got the shot were largely older
people age 70 or above who have weaker immune systems than younger
peers. The clinical trials focused largely on people 55 or
under.
It is normal for the vaccines to trigger a slightly weaker
immune response as they are initially rolled out among the elderly,
said Jeremy Brown, who advises the government. Another reason
government advisers are upbeat is that the trial results point to
the vaccines being highly effective at preventing serious disease
and death by Covid-19, Prof. Brown added, which eases pressure on
the country's health system.
Scientists have said that new variants of the virus, including
one from South Africa that has been found in the U.K. and shown
some resistance to existing vaccines, will necessitate the
development of second- and third- generation shots. Prime Minister
Boris Johnson said he anticipates that those vulnerable to the
disease will need to get an updated booster dose in the fall.
The successful rollout of the vaccine vindicates a decision by
the British government to bet big and early on vaccines. In April
last year, as the first wave of the pandemic peaked, the
government's chief scientific adviser decided that a specialized
vaccine task force needed to be set up. The government went on to
secure 400 million doses from seven different pharmaceutical
companies. U.K. regulators have already approved three vaccines for
use.
The data also offer support for another British bet: British
officials decided to spread limited initial vaccine supplies more
thinly by widening the gap between doses to up to 12 weeks from
just three weeks recommended by Pfizer and four for
AstraZeneca.
The decision, questioned by U.S. scientists and some British
medics but recently endorsed in the case of AstraZeneca by the
World Health Organization, has helped the country hit a target of
offering a first dose to the top four most vulnerable groups by
Feb. 15, who account for 88% of deaths from the disease, the U.K.
government said.
--Joanna Sugden contributed to this article.
Write to Jason Douglas at jason.douglas@wsj.com and Max
Colchester at max.colchester@wsj.com
(END) Dow Jones Newswires
February 22, 2021 16:21 ET (21:21 GMT)
Copyright (c) 2021 Dow Jones & Company, Inc.
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