The north's Covid-19 vaccination programme is set to be hit by delays after problems with a shipment of the AstraZeneca jab from India impacted the UK's supply.
British government Cabinet minister Robert Jenrick conceded that the rollout of vaccines would be slower than expected because of the shortage, while Professor Adam Finn, a member of the Joint Committee on Vaccination and Immunisation (JCVI), said vaccination of those aged under 50 "may kick off slightly later than we'd optimistically hoped".
Health Minster Robin Swann this morning said vaccinations in the north were ahead of schedule and "as ever we will be able to adapt to any changes in circumstance as they arise".
As has been the case since the programme began, the number of vaccinations carried out over time will vary due to supply however our programme is presently ahead of schedule and as ever we will be able to adapt to any changes in circumstances as they arise. 2/2
— Robin Swann MLA #StopCovidNI (@RobinSwannMoH) March 17, 2021
A delay in the delivery of five million doses of the AstraZeneca coronavirus vaccine from India is partly to blame for the forthcoming reduction in the UK's supply.
The delivery had been expected from the Serum Institute of India but has been held up by four weeks.
Patricia Donnelly, the head of the vaccine rollout in Northern Ireland, told the assembly's Health committee that plans had been flexed to make more use of Pfizer jabs pending the arrival of further AstraZeneca stock.
Ms Donnelly said plans had been flexed to make more use of Pfizer jabs pending the arrival of further AstraZeneca stock.
She confirmed said all first Covid-19 jab appointments already booked will be honoured and those expecting a second jab will also receive it.
The senior official said more people would continue to get first jabs in April but at a slightly reduced rate and that delivery issues could knock back the rollout plan by four weeks in a "worst case scenario" but the delay was more likely to be around two weeks.
"I think, worst case scenario, it probably puts us back by four weeks," she told the committee.
"The mitigation measures that we put in place we hope will only delay us by two weeks, so it won't have a huge impact."
A mass vaccination centre at Belfast's SSE Arena is due to open on March 29.
Ms Donnelly said the initial hope was that by the time the centre began operating the vaccine would be on offer to the over-40 age cohort.
She said the over-40s were now likely to have to wait for a further fortnight.
Ms Donnelly said at the latest the over 40s would be delayed until the end of April.
"We have scaled down slightly the opening weeks in the SSE Arena," she said.
"It has the capacity for 40,000 (a week) but in the first weeks we're looking at 11,000, building up to 20,000 and then up to 30,000 in subsequent weeks."
Ms Donnelly added: "We had hoped by the time we would launch the SSE Arena that we would be opening to the over-40s.
"I think that will be maybe delayed by two weeks but we'll keep that under review and it will very much depend on the remaining deliveries that we get from AstraZeneca."
Ms Donnelly continued: "We have tried to find some mitigation through further use of the Pfizer vaccine.
"So, it will slightly delay it, but it won't, I think, reduce our plans overall."
She said the supply of Pfizer jabs had remained steady throughout and she expected that to continue going forward.
Explaining the adjusted rollout plan, Ms Donnelly said three of Northern Ireland's five health trusts would now rely mainly on Pfizer in the coming weeks pending the arrival of more AstraZeneca jabs.
A delay in the delivery of five million doses of the AstraZeneca coronavirus vaccine from India is partly to blame for a forthcoming reduction in the UK's supply.
Ms Donnelly characterised that vaccine delivery as a bonus that the authorities in Northern Ireland had not initially been expecting.
"This vaccine that is delayed was a bumper delivery schedule that we hadn't expected," she said.
"This came very late, this announcement that we would be getting this.
"So, in some ways, we hadn't counted on it.
"We very much welcomed it.
"So while it's disappointing, our plans are not offset too badly by it.
"We have got increased amounts of Pfizer and I think that's been always very steady for us.
"So that's enabled us to have offset it in some way.
"So we're in constant communication around that and hopefully our steady supply that we've had up to date will continue through the month of March, we've no reason to believe it won't."
Robert Jennnick told BBC Breakfast the final goal of vaccinating all adults in the UK with one dose by the end of July was still on track.
However, vaccination and rollout figures suggest the NHS had been set to easily beat that target.
Mr Jenrick said: "We are experiencing some supply issues so it does mean the vaccine rollout will be slightly slower than we may have hoped, but not slower than the target we set ourselves.
"We're going to move forward as quickly as we possibly can but it won't be as fast as we might have hoped for a few weeks, but then we have every reason to believe that supply will increase in the months of May, June and July."
He said the British government had learned of coronavirus vaccine supply issues "in the last few days", and suggested the problem is not due to reductions from a single nation.
"We have learned from some of our manufacturers that there are going to be some supply issues in the last few days," he told BBC Radio 4's Today programme.
"A number of global manufacturers are experiencing issues."
Pressed if the issue was vaccine coming from India, he said: "It's not that there's any one factory responsible for this or any one country."
Dr Alan Stout, chair of BMA’s Northern Ireland general practitioners committee, said: “It is frustrating but perhaps unsurprising that there are potential issues with the supply of covid vaccines across the UK.
“From the outset the pace of the vaccination programme has depended on the supply. It is crucial that the Department of Health provide timely updates on vaccine supply, especially to primary care who are a central cog in the delivery of the vaccine programme to patients across Northern Ireland.
“It is also important to remember that the vast majority of those most at risk have already been given their first dose and the vaccination programme is ahead of schedule in Northern Ireland.
"This is a UK-wide problem, however I am hopeful that Department of Health will address this issue as a matter of urgency.
"Practices remain fully committed to vaccinating their patients as quickly as they possibly can.”
Prof Finn, from the University of Bristol and a member of the JCVI, told Today that "vaccines are definitely tricky when it comes to supply".
He added: "Historically we've always tried in the UK to have more than one supplier of more than one vaccine, whenever possible, because this does come up from time to time.
"And I think even more so then at the present time, because these vaccines are new technology, and manufacturing them at scale is quite tricky."
Prof Finn said the current aim was to complete priority groups 1-9 (aged 50 and above plus health conditions) but also "to deliver on those second doses because JCVI has been very clear from the outset that those second doses must be given in order to provide the long-term protection that people need".
He said the 12 weeks between first and second doses must "not be allowed to slip significantly and I think it may mean that the next phase, phase two (under-50s), may kick off slightly later than we'd optimistically hoped".
A letter to health leaders in England, published on Wednesday, warned of a "significant reduction in weekly supply" of the vaccine from March 29, "meaning volumes for first doses will be significantly constrained".
The letter from Emily Lawson, NHS chief commercial officer, and Dr Nikita Kanani, medical director for primary care, said people "aged 49 years or younger should not be offered vaccination" unless they are in a higher priority group, such as being clinically vulnerable.
It added that the UK's vaccines taskforce predicts the shortfall will last four weeks "as a result of reductions in national inbound vaccines supply".
A spokesperson for the Serum Institute of India told the BBC: "Five million doses had been delivered a few weeks ago to the UK and we will try to supply more later, based on the current situation and the requirement for the government immunisation programme in India."
AstraZeneca has partnered with the institute, which is the world's largest vaccine manufacturer, for supplies to the Indian government but also to other countries, including low and middle-income ones.
It comes as the European Medicines Agency (EMA) is to deliver its verdict on the safety of the AstraZeneca vaccine after more than a dozen European countries halted its rollout over fears regarding blood clots.
