Stephen Donnelly (Wicklow, Fianna Fail) | Oireachtas source

It is a really good question. The scientific and medical community cannot answer it yet because the vaccines are being administered for the very first time. There are several unknowns at the moment including the impact on transmissibility, more detail on the effectiveness and the duration of protection, as referred to by Deputy O'Donnell. Those things are not known right now. It could be an annual situation like the flu vaccine, or maybe people will get protection for several years as with other vaccines. We do not know yet.

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