Long queues have formed at major vaccine centres this morning, with some now at capacity for the day and turning people away.
Walk-in clinics were opened to people aged 40-49 this morning, as appointments continue for other groups.
Twenty-three clinics across Ireland are taking people in the 40-49 age group for booster jabs without an appointment this morning for the first time.
The HSE has redeployed staff from other areas of the health service to maximise capacity at clinics.
But the pressure of high demand for boosters is showing clearly already today.
In Dublin, the clinic at the National Show Centre in Swords closed its gates at 8.30am this morning, just 15 minutes after it opened.
While the queue at CityWest in Tallaght is estimated at three hours long. Local woman Olivia McMahon says it is still moving though.
She told Newstalk: "We've been queueing for nearly 50 minutes, but it is moving, there was very heavy traffic coming into CityWest earlier. We just parked our car up in the village because there was heavy traffic from all directions coming in."
There's a similar wait at the Shoreline clinic in Greystones, Co Wicklow.
In Co Meath, the clinic at Simonstown GAA grounds in Navan has a two-hour line, and people are being urged to come back after 1pm.
Officials are also telling people planning on visiting the Galway Racecourse clinic to come back later with a two-hour wait there.
The queue at City Hall, the main clinic in Cork City, is said to be lengthy, but moving well with just a 20-minute wait.
The full list of opening times for walk-in centres on Sunday is as follows:
Carlow:
- Woodford Dolmen Hotel: Boosters for 40 years and older: 2pm to 5pm, Healthcare workers: 2pm to 5pm
Cavan:
- Kilmore Hotel: Boosters for 50 to 69-year-olds: 10.00am to 12.30pm, Healthcare workers: 10am to 12.30pm (over 30), 1.30pm to 5pm (under 30 only), Dose 1 and 2: 1.30pm to 5pm.
Clare:
-West County Hotel: Boosters for 40 years +: 1.30pm to 7pm
Cork:
- City Hall: Boosters for 40 years +: 8am to 8pm, Healthcare workers over 30: 8am to 8pm
- Mallow: Boosters for 40 years +: 9.15am to 4.15pm
- Bantry: Boosters for 40 years +: 9.30am to 4pm, Dose 1 and 2: 9.15am to 4.15pm
Donegal:
- Letterkenny: Boosters for 40 years + and healthcare workers: 9am to 7pm
Dublin:
- CityWest: Boosters for 40 years +: 8.30am to 12.30pm
- National Show Centre: Boosters for 40 years and older, healthcare workers and dose 1 and two: 8.15am to 11.15am, 12.40pm to 4pm, 5.20pm to 7.10pm
Galway:
- Galway Racecourse: Boosters for 40 years and older: 8.30am to 2pm
Kildare:
- Punchestown Racecourse: Boosters for 40 years and older: 9am to 12pm: Healthcare workers: 9am to 12pm
- St. Fintan’s Campus: Boosters for 40 years and older: 9am to 6pm, Healthcare workers over 30: 9am to 6pm
Limerick:
- Scoil Carmel, Limerick: Boosters for 40 years and older and healthcare workers : 8.30am to 7pm
Mayo:
- Breaffy House: Boosters for 40 to 49-year-olds: 8.30am to 1pm, 2pm to 7.45pm, Boosters for 50 to 59-year-olds: 9.30am to 1pm, 2pm to 5.15pm
Meath:
- Simonstown GAA Club : Boosters for 40 to 49-year-olds: 8.30am to 6.30pm
Monaghan:
- Glencarn Hotel: Boosters for 40 years and older and healthcare workers over 30: 9.30am to 12.30pm, 1.30 to 5pm
Offaly:
Offaly Vaccination Centre: Boosters for 40 years and older and healthcare workers: 9am to 3pm
Roscommon:
Roscommon VC: Boosters for 40 to 49-year-olds: 8.30am to 1.30pm, 2.30 to 7.30pm, 50 to 59-year-olds: 2.30 to 7.30pm
Sligo:
- Sligo Racecourse: Boosters for 40 years and older and healthcare workers: 8.30am to 7.30pm
Tippeary:
- Abbeycourt Hotel: Boosters for 40 years and older: 8.30am to 7pm
Waterford:
- Waterford IT: Boosters for 40 years and older: 8.15am to 4pm, Healthcare workers: 8.15am to 5.15pm
Westmeath:
Westmeath Community Vaccination Centre: Boosters for 40 years and older: 2pm to 6pm, Healthcare workers over 30: 2pm to 6pm
Wexford:
-Astro Active Centre: Boosters for 40 years and older: 3pm to 7pm, Healthcare workers: 3pm to 7pm, Dose 1 and 2: 3pm to 7pm
Wicklow:
- Shoreline Leisure Centre
Boosters for 40 years and older: 8.30am to 12.30pm, 2.30pm to 6.30pm
