NHS Wales is giving more than 35,000 booster jabs a day after ramping up the vaccination programme in response to the spread of the Omicron variant.
Each of the four UK nations has seen a massive surge in the number of third jabs being administered as the PM announced an ambitious target for every adult to be boostered by the end of the year.
UK health chiefs aimed to deliver a record number of booster jabs over the weekend with appointments made available at mass vaccination centres in football stadiums as well as hospitals, community facilities and pharmacies.
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In Wales, just over half (53.5%) of all people aged 18 and over have now received their third jab- slightly behind England (54.8%) and some way off Scotland (57.7%).
Welsh minister Eluned Morgan said booster vaccinations would be offered to all eligible adults by the end of January and people would still be called in priority order of age and vulnerability. The delay between the second and third jabs has also been cut from six months to just three.
The rush to get jabbed has seen some enormous queues right across the UK, with some people waiting up to five hours in Scotland last week. There were similar scenes in south Wales although few people seemed bothered by the wait with one man saying: "I didn't mind - the fact so many people were there shows that people are turning up to get their boosters and that's really encouraging."
The round the clock "jabathon" has seen some confusing messages about whether health boards in Wales were accepting walk-ins as well as booked appointments. Last week, Mark Drakeford told ministers that "the major thrust" in Wales had been to offer boosters in line with the JCVII advice, which is to invite people in order of clinical priority.
However, in order to prevent slots going unfilled, some people are being called in out of order to make sure vaccinators aren't standing empty handed and vaccines don't go unused, an approach that's been used throughout the vaccination roll out.
Mr Drakeford said it was impossible to "turn the tap on overnight" in response to a question about the length of time it's taken some people to arrange their booster jab. He appealed to people for patience- the system is "working as fast as it can and as flat out as it can", he said, but the sheer numbers of people calling the system means there have been delays.
Read more: On the frontline of the Covid vaccine booster roll-out in Cardiff and the Vale of Glamorgan
Five out of seven health boards are not yet offering booster drops-ins, unlike in Scotland and England where walk-in centres are supposed to play a major part in the rollout. There are fears however that large swathes of England, including several major cities, have no walk-in facilities and the UK government is is danger of missing its target of offering all adults a booster jab by the end of this month.
The Guardian reported on Sunday how thousands seeking a third vaccination without having to wait days or weeks for an appointment are driving miles to neighbouring counties. And several cities, including Norwich, Peterborough and York, have no walk-in centres advertised on NHS websites while there are no walk-in boosters available in entire counties, including Oxfordshire and Buckinghamshire
The third jab offers people increased protection from the rapidly spreading Omicron variant, which has now recorded 435 confirmed cases in Wales.
The absolute number of people getting their booster jab or third injection every day is show in the below chart.
All four nations have seen a marked jump in the daily number of people getting their jabs in the last few days, although this trend is least clear in Northern Ireland.
Even so, more than a third of people in one part of Wales failed to show up for their booster jab appointments over the weekend.
The Welsh Government said it was aiming in the coming weeks to almost double the rate vaccinations are being administered to more than 200,000 a week. In the last week, it managed 240,000 booster jabs alone. It means that at least three-quarters of the more vulnerable groups have now been given their boosters and benefit from the added protection that it provides.
It's also been confirmed that 98 armed forces personnel have been made available to support the Covid-19 vaccine booster programme in Wales.
Welsh Conservative and Shadow Minister Russell George MS said: "Whilst it is encouraging that all indications show Omicron is a milder form of the virus, it is more transmissible and it’s clear booster jabs are a vital defence against the variant. Therefore, it is essential that government infrastructure is geared up to deliver boosters on a war-like scale."
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