Last update June 24th 2021
We have now concluded our Covid 19 vaccination service. If you have not yet received your vaccine please visit the HSE website or phone the HSE helpline on 1850 24 1850 for further information.
Information about Covid Vaccines
The Pfizer/Biontech vaccine (Comirnaty) was the first vaccine approve by the European Medicines Agency and is currently in use in Ireland. This vaccine does not contain any actual virus so it is not possible to get Covid-19 infection from it. Instead, it uses messenger RNA to “teach” our immune cells how to create anti-bodies against the spike proteins on the Covid-19 virus. The spikes on the coronavirus are what allow it to attach to healthy cells and cause disease so destroying these effectively kills the virus.
Side effects from this vaccine include soreness at the injection site, fatigue, headache and fever. These are usually mild and transient. Two vaccinations with 0.3mls of the vaccine at least 21 days apart are required.
The Moderna vaccine was the second vaccine to be used here in Ireland is similar to the Pzfizer one in that it also uses messenger RNA to stimulate the body to develop antibodies against the Covid-19 virus. It also has to be stored at very low temperatures and so it will be challenging to deliver this vaccine in General Practice. Two doses are required to develop adequate immunity.
Side effects include tenderness, swelling and redness around the injection site as well as aches and pains, fever and headache. These occur in about one in every ten doses given and are more likely on the second dose.
More detailed information on how both the Pfizer and Moderna vaccine work with detailed illustrations can be got from this article from the New York Times newspaper.
This vaccine has a different mode of action than the other two and is a lot more stable. This vaccine hides tiny strands of DNA inside another virus called an adenovirus. These are well known viruses and are generally associated with the common cold. The adenovirus contained in the vaccine gets into the body’s immune cells and prompts it to produce antibodies against the spike proteins on the covid-19 virus. Once these are formed the body kills off the Covid-19 virus once it enters the body.
Two vaccines are required and similar side effects to the vaccines above are associated with the AstraZeneca vaccine. The interval between the two vaccine administrations is now 12 weeks.
The AstraZeneca vaccine has been assosciated with a rare condition which causes low blood platalets and blood clotting. Although the incidence of this adverse reaction is only between 4 and 10 per million people who receive the vaccine, our vaccination governing body (NIAC) have decided that it should only be given to people over 60. This is an evolving story and this guidance may change as the weeks go by. For more information on the risks of clotting and advice on who should not receive this vaccine please click here.