Ireland is party to six bulk- buying contracts negotiated by the European Union, which, if all the vaccines are approved, could see upwards of 10 million doses for the State. They include:
Pfizer/BioNTech vaccine (2.3 million doses)
This is being administered from today.
The first shipment of 10,000 doses of the Pfizer vaccine arrived in Ireland on Saturday.
An additional 30,000 doses of the Pfizer vaccine are due for delivery next week, with 40,000 doses due each week through January and into February.
Moderna vaccine (875,000 doses)
The EU has ordered a further 80 million doses of the Moderna vaccine and brought forward plans to assess the shot for approval in Europe.
The European Medicines Agency (EMA) is to issue its verdict on conditional marketing authorisation on January 6.
HSE boss Paul Reid said the State was "in dialogue" with Moderna regarding its delivery schedule and roll-out.
Oxford-AstraZeneca vaccine (3.3 million doses)
The UK plans to roll this out from January 4.
However, Ireland may have to wait a while longer.
An EMA official said yesterday it was unlikely that the vaccine would be recommended for approval by the EMA next month.
The agency's deputy executive director, Noel Wathion, said the EMA does not have enough information about the vaccine.
"At the moment, AstraZeneca has only provided data on their clinical trials to the European Medicines Agency," he said.
More like a standard vaccine, it will be considerably easier to administer as it does not require very cold storage as is the case with the Pfizer-BioNTech and Moderna jabs, which are new mRNA vaccines.
Janssen vaccine (2.2 million doses)
It is expected that approval for the single-dose Johnson & Johnson vaccine, which is currently in phase three clinical trials involving 45,000 people, will be sought in the first half of 2021.
Sanofi vaccine (3.3 million doses)
Two weeks ago, Sanofi announced that its Covid-19 vaccines will not be ready until the end of 2021, after interim results showed a low immune response in older adults.
CureVac vaccine (no details on order yet)
German biotech group CureVac launched its final-stage trial earlier this month.
The company, which uses a similar mRNA platform to vaccines developed by BioNTech/Pfizer and US rival Moderna, is unlikely to apply for regulatory approval until the middle of next year.