Explainer: What vaccine options are open to the under-35s?

J&J and AstraZeneca vaccines at a pharmacy or longer wait for mRNA jab among options

People aged 18-35 can seek an mRNA vaccine when registration opens or go to a pharmacy for a Janssen or AstraZeneca jab. Photograph: iStock

Young people aged between 18 and 34 have a number of options for vaccination against Covid-19 over the coming weeks.

Probably the fastest route to full vaccine protection is by immunisation with the one-shot Janssen (Johnson & Johnson) vaccine. More than 750 pharmacies around the country began administering this vaccine to this age group on Monday.

However, with initial capacity constrained by limited stocks, many individual pharmacies have closed their registration lists for now due to high demand.

Young people are being vaccinated in pharmacies from a supply of 60,000 doses that was originally provided to the sector for use in over-50s. Only 8,000 of this supply was used for the older age-group, leaving significant quantities available now for the 18-34 year-olds.


The HSE has another 70,000-80,000 doses of Janssen vaccine in stock, which will be distributed shortly. A further 80,000 doses are due to arrive in Ireland this month.

Those eligible are being encouraged to register with just one pharmacy, but it is thought likely that multiple registrations will occur, leading to duplication of effort.

A “push” model is being used to supply pharmacists, so that supplies will be replenished once the initial delivery has been administered.

mRNA vaccines

Under the twin-track approach of the HSE, from next week, a second vaccination option opens up for the 18-34 year-olds. From then, they will be able to register to receive the Janssen or AstraZeneca through the HSE portal, with most doses subsequently delivered at one of the mass vaccination centres across the country.

The second dose of AstraZeneca is now being administered at a four-week interval from the first.

People who register in this way will be called in reverse age order, ie, the oldest among the 18-34 -year-olds first.

If a person in this age group wishes to be immunised with an mRNA vaccine (Pfizer or Moderna) instead, they can indicate their preference during the registration process.

A HSE spokesman was unable to say how quickly young people would be able to access mRNA vaccines, as this depended on uptake in other categories.

The HSE is currently vaccinated people aged 35 years and up, and expects to complete this age cohort “next week or the week after,” the spokesman said.

From Friday, people aged 30-34 years will be invited to register through the HSE portal for an mRNA vaccine, with the shot being administered within the following three-week period. Registration for 25-29 year-olds is likely to follow shortly after.

Last week, the State received delivery of 318,000 doses of Pfizer vaccine, and 300,000 of AstraZeneca. The latter is required for second doses for over-60s, as well as use among younger age groups.

Some 343,000 doses of the four authorised vaccines were administered last week. By Tuesday, over half of the adult population will have been fully vaccinated.

Paul Cullen

Paul Cullen

Paul Cullen is a former heath editor of The Irish Times.