The Minister for Health urges people to come forward for a booster vaccine.
NIAC have recommended that the interval between the primary vaccine series and booster dose should be reduced to three months.
It has also recommended a booster (fourth dose) of an mRNA vaccine no sooner than three months after their third dose for those who are immunocompromised and for whom a third dose had been previously recommended as part of an extended vaccine schedule.
NIAC have also recommended that those individuals who have received one dose of a two-dose primary vaccine schedule and who subsequently have a confirmed SARS-CoV-2 infection, should complete their primary vaccination course four weeks after diagnosis or onset of symptoms.
It has reiterated that vaccine booster doses should continue to be offered in the priority order previously recommended.
The Minister for Health, Stephen Donnelly TD, has accepted the new recommendations in relation to the COVID-19 vaccination programme.
The recommendations were made by the National Immunisation Advisory Committee (NIAC) to the Chief Medical Officer (CMO), who has endorsed these recommendations.
Minister Donnelly said: “Decreasing the interval for booster doses is an important step given Ireland’s current epidemiological situation and the increasing concern we have about the spread of the Omicron variant.
"This step should serve to reduce serve disease, hospitalisation and deaths, as well as having an impact on infection rates.
“Vaccination, along with our continued adherence to the public health advice offer the best protection we have against the current wave of infection driven by the Delta variant, and as we wait further evidence relating to the impact the Omicron variant may have.
“Continue to avoid crowds and reduce your contacts, wear a mask, including in crowded outdoor environments, keep your distance - if you feel unsafe, feel empowered to leave, open windows and avoid poorly ventilated indoor spaces and clean your hands regularly.
“Do not wait until after Christmas to receive your booster vaccine or come forward for your first dose, the benefits of receiving your booster dose far outweigh any potential risks that may arise in the meantime," he insisted.
The Department of Health and the HSE has said it will now work to put these updates into operation.

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