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* Britain has offered shots to high-priority groups
* Johnson: lockdown largely behind lower cases
* PM cautions there will be more hospitalisations, deaths
* Moderna rollout begins in England
* Surge testing in London to track South Africa variant
(Recasts with Johnson, adds detail from health service)
By Alistair Smout and Sarah Young
LONDON, April 13 (Reuters) - British Prime Minister Boris
Johnson warned on Tuesday that the rapid drop in COVID-19 deaths
was largely down to a three-month lockdown, not the vaccination
programme, and that cases would rise once again as restrictions
ease.
The United Kingdom launched its inoculation drive in
December and has already offered a first shot to all over-50s,
the clinically vulnerable and health workers. The country is
behind only Israel in the proportion of its population to have
received at least one dose.
That rollout was however followed a month later by a third
lockdown in early January to tackle surging infections driven by
the "Kent" variant of the virus. Since February, daily infection
numbers, hospitalisations and deaths have all dropped sharply.
"The bulk of the work in reducing the disease has been done
by the lockdown," Johnson said on Tuesday, adding there was no
reason to change the roadmap for reopening the economy.
"As we unlock the result will inevitably be that we will see
more infections and sadly we will see more hospitalizations and
deaths."
With conditions improving, England reopened all retail,
hairdressers, gyms and pub gardens on Monday and Scotland,
Northern Ireland and Wales are due to reopen different elements
of their societies in the coming weeks.
The vaccine rollout also got a boost on Tuesday when Moderna
became the third vaccine to be offered in England after
AstraZeneca and one from Pfizer-BioNTech .
That will help keep Britain on track to hit its target of
offering all adults a vaccine by the end of July.
Moderna, already offered in the United States and Europe,
uses the same mRNA technology as Pfizer's shots but can be
stored at normal fridge temperatures unlike its rival U.S.
vaccine, which must be kept and shipped at ultra-low
temperatures.
On Tuesday, NHS England said that people aged 45 or over
could now book appointments to receive a COVID-19 vaccine.
For those categories already offered a vaccine, it said that 95%
of people who were eligible had taken up the offer.
However, in another note of caution to the optimism, the
government announced an expansion of so-called surge testing in
the south London boroughs of Lambeth and Wandsworth to detect
cases of the variant first found in South Africa.
There have been 74 confirmed and probable cases of the
coronavirus variant, known as B.1.351, in the boroughs, and
there is concern that vaccines are less effective against it.
"The important thing will be to watch: If the South African
variant has really taken off, and we'll probably know in about
two to three weeks, then we may need to pause re-opening a
little bit," James Naismith, professor of structural biology at
the University of Oxford and director of Rosalind Franklin
Institute, told BBC Radio.
With more than 127,000 fatalities, the United Kingdom has
the fifth-highest death toll in the world from COVID-19.
(additional reporting by Paul Sandle; Writing by Kate Holton;
Editing by Nick Macfie, Jon Boyle and Chizu Nomiyama)
