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* AstraZeneca, Novavax say their shots protect from Omicron
* UK data suggests fewer hospitalisations than from Delta
* Don't extrapolate from similar SAfrican data -African CDC
* WHO also urged caution about drawing firm conclusions
By James Macharia Chege and Josephine Mason
JOHANNESBURG/LONDON, Dec 23 (Reuters) - Omicron advanced
across the world on Thursday, with health experts warning the
battle against the COVID-19 variant was far from over despite
two drugmakers saying their vaccines protected against it and
signs it carries a lower risk of hospitalisation.
Coronavirus infections have soared wherever the highly
infectious Omicron variant has spread, triggering new
restrictions in many countries and record new cases.
But in another glimmer of hope two days before Christmas, a
U.S. Federal Drug Administration official said that data
indicated that both Merck's and Pfizer's
COVID-19 anti-virals are effective against the coronavirus
variant.
There were encouraging signs too about hospitalisation rates
from Britain and South Africa, although the head of a leading
African health agency joined the World Health Organization in
cautioning that it was too soon to draw broader conclusions.
"Let's be careful not to extrapolate what we are seeing in
South Africa across the continent, or across the world," Africa
Centres for Disease Control (CDC) chief John Nkengasong said.
Nevertheless, U.S. stock indexes and yields on U.S.
Treasuries both climbed on Thursday, partly on new optimism.
"Today is a very calm day. It’s the relief over Omicron
apparently not being as bad as we feared," Ryan Detrick, chief
market strategist at LPL Financial, said.
First identified last month in southern Africa and Hong
Kong, Omicron is becoming dominant in much of Europe including
Britain https://www.reuters.com/world/uk/englands-covid-19-prevalence-reaches-record-1-45-people-ons-2021-12-23,
where daily new infections have soared beyond 100,000.
In France, daily coronavirus cases - currently close to
90,000 - could rise into the hundreds of thousands in January, a
scientific adviser to President Emmanuel Macron said on
Thursday, while Germany reported its first Omicron death and
Serbia reported its first Omicron case.
In Italy, the first Western country to be hit by the
pandemic last year, the National Health Institute said Omicron
would soon predominate, while Greece banned public Christmas
festivities to curb its spread. Both countries also made outdoor
mask-wearing mandatory.
But increases in hospitalisations and deaths in South Africa
and Britain since Omicron took hold appear to have been only
gradual, and AstraZeneca https://www.reuters.com/business/healthcare-pharmaceuticals/astrazeneca-shot-third-dose-works-against-omicron-study-2021-12-23
and Novavax https://www.reuters.com/business/healthcare-pharmaceuticals/novavax-says-covid-vaccine-boosts-response-omicron-variant-2021-12-22
joined other manufacturers in saying their shots
protect against it.
University of Edinburgh https://www.reuters.com/business/healthcare-pharmaceuticals/scotland-reports-fewer-covid-19-hospitalizations-with-omicron-2021-12-22
researchers who tracked 22,205 Omicron patients said on
Wednesday the number who needed to be hospitalised was 68% lower
than they would have expected, based on the rate in patients
with Delta.
Imperial College London https://www.reuters.com/business/healthcare-pharmaceuticals/hospital-stay-risk-omicron-is-40-45-lower-than-delta-uk-study-2021-12-22
researchers reported evidence of a comparable 40%-45% reduction
in hospitalisation risk.
Britain recorded a record number of new coronavirus cases on
Thursday as Omicron swept the country, with the daily tally
reaching 119,789 from 106,122 a day earlier.
But analysis of preliminary data by the UK Health Security
Agency showed an individual with Omicron was estimated to be
between 31% and 45% less likely to attend hospital compared to
someone with Delta, and 50% to 70% less likely to be admitted.
UKHSA boss Jenny Harries said this was "an encouraging early
signal", but added: "this is early data and more research is
required to confirm these findings".
The U.S. Food and Drug Administration authorised Merck's
anti-viral pill for certain high-risk adult patients, a day
after giving the go-ahead to a similar treatment from
Pfizer.
Both pills worked, a top FDA official said.
"The available data that we have indicates that both
paxlovid and molnupiravir are effective against Omicron," said
Patrizia Cavazzoni, adding that both interfere with how the
virus replicates, a process that is not altered across variants.
'DON'T OVER-INTERPRET'
Raghib Ali, senior clinical research associate at the
University of Cambridge, said scientists had warned that, with
the surge in cases in Britain, even a small proportion of
hospitalisations could overwhelm the healthcare system.
The British data supported findings from South Africa's
National Institute for Communicable Diseases (NICD).
A separate South African government-backed study, yet to be
peer-reviewed, on health workers given the Johnson & Johnson
vaccine identified "clear and early de-coupling" of
hospitalisation from Omicron cases compared with Delta.
However, the CDC's Nkengasong said the NICD data, suggesting
Omicron was 70%-80% less severe than Delta, should be
interpreted "with a lot of caution".
AstraZeneca said a three-course dose of its vaccine offered
protection against the variant, citing data from an Oxford
University lab study.
Findings from the study, yet to be published in a
peer-reviewed medical journal, matched those from rivals
Pfizer-BioNTech, and Moderna.
Hours earlier, Novavax said early data showed its
vaccine - authorised for use by the European Union and WHO but
yet to be approved by the United States - also generated an
immune response against Omicron.
But the older Delta variant lurks.
The coronavirus death toll in Russia, where officials had
detected only 41 Omicron cases, passed 600,000 on Thursday,
Reuters calculations based on official data showed, after a
surge of Delta-linked infections.
Only the United States and Brazil have recorded more
coronavirus deaths.
Interactive graphic tracking global spread of coronavirus:
open https://tmsnrt.rs/2FThSv7 in an external browser.
Eikon users can click https://apac1.apps.cp.thomsonreuters.com/cms/?navid=1063154666
for a case tracker.
(Reporting by Reuters bureaux around the world; Writing by John
Stonestreet and Nick Macfie; Editing by Catherine Evans, Edmund
Blair, Mark Heinrich and Alexander Smith)
