Ireland will receive 300,000 fewer doses of Covid-19 vaccines in the first three months of this year due to supply issues with the AstraZeneca jab, the head of the national vaccination taskforce has confirmed.
Professor Brian MacCraith told an Oireachtas committee that Ireland now expects 1.1 million doses of vaccines to be delivered by the end of March, rather than the original 1.4 million.
It means that 550,000 people can be vaccinated in that period - about 150,000 fewer than the Government's 700,000 target.
Prof MacCraith added that there is no certainty over the supply of vaccines from April onwards.
"We have a level of confidence for this quarter," he said, adding that that confidence has been dented due to the AstraZeneca production issues.
"The assurances we had received indicated 1.4 million doses across AstraZeneca, Pfizer and Moderna. The simple calculation, given they're all dual doses, leads to 700,000 people being vaccinated.
"However, as we learned in recent days, AZ has indicated a significant drop. So that 1.4 million doses has dropped to just above 1.1 million doses."
Prof MacCraith said he expects the drop in the delivery of the AstraZeneca vaccine to be a 50% reduction in the next two months.
"The totality for quarter one now is 286,000, when we have been planning on expecting 600,000 doses of AstraZeneca," he said.
"So that gives you that approximate 50% reduction."
But he added that those figure may change again depending on the outcome of the negotiations between AstraZeneca and the European Commission, and depending on deliveries of other vaccines.
As of January 27, a total of 161,500 vaccines have been administered to long-term care home residents and staff and frontline healthcare workers.
TDs and senators were told that an average of 48,000 doses of vaccine have been administered per week over the past three weeks.
"We're sticking to the principle of administering vaccines as soon as they arrive," Prof MacCraith said.
"We're right to the edge of the supply that's available. There are no vaccines resting in the fridges or freezers in any given week."
Prof MacCraith and representatives from the HSE appeared before the Health Committee on Friday to provide an update on the rollout of Covid-19 vaccines.
TDs and senators were told that the HSE is working towards providing daily updates on the vaccination rollout, but no fixed date for these was given.
The HSE's lead for the vaccination plan and workforce, David Walsh, said he does not know how many care residents and staff of care homes have yet to be vaccinated.
He told the committee there are 117 nursing homes where "substantial numbers" could not be vaccinated because they were either ill or had been ill within four weeks of the doses being administered.
He also said there are 400 residents and staff of four nursing homes who have not been vaccinated on public health advice due to the severity of Covid-19 outbreaks.
Under the Government's plan, all residents and staff at nursing homes were due to be vaccinated by last Sunday.