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By Andrew MacAskill
LONDON, Jan 2 (Reuters) - Britain will allow people to be
given shots of different COVID-19 vaccines on rare occasions,
despite a lack of evidence about the extent of immunity offered
by mixing doses.
In a departure from other strategies globally, the
government said people could be given a mix-and-match of two
COVID-19 shots, for example if the same vaccine dose was out of
stock, according to guidelines published on New Year's Eve.
"(If) the same vaccine is not available, or if the first
product received is unknown, it is reasonable to offer one dose
of the locally available product to complete the schedule,"
according to the guidelines.
Mary Ramsay, head of immunisations at Public Health England,
said this would only happen on extremely rare occasions, and
that the government was not recommending the mixing of vaccines,
which require at least two doses given several weeks apart.
"Every effort should be made to give them the same vaccine,
but where this is not possible it is better to give a second
dose of another vaccine than not at all," she said.
COVID-19 has killed more 74,000 people in Britain - the
second-highest death toll in Europe, and health officials are
racing to deliver doses to help end the pandemic as fears grow
that the health service could be overwhelmed.
Earlier this week, the government reactivated emergency
hospitals built at the start of the outbreak as wards fill up
with COVID-19 patients.
Britain has been at the forefront of approving the new
coronavirus vaccines, becoming the first country to give
emergency authorisation to the Pfizer/BioNTech and the
AstraZeneca/University of Oxford vaccines last month.
Both vaccines are meant to be administered as two shots,
given several weeks apart, but they were not designed to be
mixed together.
The government's new guidelines said there "is no evidence
on the interchangeability of the COVID-19 vaccines although
studies are underway".
However, the advice said that while every effort should be
made to complete the dosing regimen with the same vaccine, if
the patient is at "immediate high risk" or is considered
"unlikely to attend again" they can be given different vaccines.
Britain sparked controversy earlier this week by announcing
plans to delay giving the coronavirus vaccine booster shot in an
attempt to ensure more people could be given the more limited
protection conferred by a single dose.
The top U.S. infectious diseases expert, Anthony Fauci, said
on Friday he did not agree with the British approach of delaying
the second dose up to 12 weeks.
"I would not be in favour of that," he told CNN. "We're
going to keep doing what we're doing."
(Reporting by Andrew MacAskill
Editing by Helen Popper)
