The HSE has moved to upgrade its vaccination portal and booking system in a move to resolve the issue of multiple appointments and no-shows.
The issue emerged in recent days and was even the subject of a testy discussion in the Dáil where the Taoiseach said large numbers of appointments were not being taken up.
It comes as the HSE has this morning had to warn people not to attend the walk-in booster clinic at UCD due to "very large queuing times."
Some 600 people have turned up to the walk-in clinic for the over 50s, but the centre only has the capacity to deal with 100 people per hour.
The HSE’s national lead for the vaccination programme has acknowledged the “vagaries” of the system and problems with databases, following confusion around the number of people who have got their booster shot.
Damien McCallion said that the priority was to ensure maximum choice and maximum capacity.
Earlier this week, the Taoiseach told the Dáil that between November 22nd and 28th, a total of 208,000 appointments were issued but only 80,000 people turned up.
Micheál Martin said between November 29nd and December 5th, another 180,000 appointments were issued but only 93,000 showed up.
Time lag
Mr McCallion said the time lag between the HSE’s vaccination database and the IT systems used by pharmacies and GPs was being addressed, and he accepted that the system had not worked as smoothly as it should.
There had been a further upgrade to the HSE’s system last night, he told RTÉ radio’s Morning Ireland.
If people were vaccinated in a pharmacy or at their GP then it would be recorded in the system and the issue of multiple appointments would cease.
Pharmacies and GPs, both of whom offer the booster, have reported delays in people being marked as having had the jab in the main HSE database.
Darragh O’Loughlin, general secretary of the Irish Pharmacy Union (IPU) told RTÉ that if somebody got their booster vaccine in a pharmacy their details were entered into the Pharmavax system, which is a HSE developed and owned system that feeds the national CoVax database.
“The details are going in from the pharmacy as we are doing the vaccine, but when they transfer over to that central CoVax database, it doesn't automatically trigger a cancellation of a booster appointment.
“What that means is that people are having a vaccine in a pharmacy — they are getting a booster, they are going home — and then a day or two later they might be issued an appointment in a vaccination centre by text and they are then struggling to cancel that appointment."