Vaccines versus Delta: How much protection does each vaccine give? 

There are now four vaccines in Ireland for over-18s, and one for medically vulnerable teens aged 16 and 17.

There are now four vaccines in Ireland for over 18s, and one for medically vulnerable teenagers aged 16 and 17.

They all give strong protection against Covid-19 but they are not 100% effective. 

Mild illness is likely the worst outcome for vaccinated people. 

Johnson & Johnson:

This vaccine is now available for over 18s at pharmacies or mass vaccination centres.

A study this week in the New England Journal of Medicine on protection levels, including against the Delta variant, said: “Johnson & Johnson’s single-dose Covid-19 vaccine was 85% effective against severe/critical disease.” 

The vaccine offered “prevention against Covid-19-related hospitalisation and death across all participants”.

This data also shows immunity lasts at least eight months. Further studies are ongoing.

The vaccine kicked in after seven days for “severe/critical disease” and after 14 days for “moderate to severe/critical disease”.

AstraZeneca:

Can now be given to over 18s at mass vaccination centres and hospitals.

New real-world data published two weeks ago by Public Health England (PHE) shows this vaccine is 92% effective against hospitalisation with severe illness from the Delta variant after two doses. 

The study showed no deaths among those vaccinated. The analysis included 14,019 cases of the Delta variant.

A PHE study in May found 67% efficacy against the symptomatic disease of the Delta variant.

Pfizer:

This vaccine can be given to over 18s at GPs, mass vaccination centres, for vulnerable teens high on the priority list, aged 16 and 17, and pregnant women. 

New real-world data published by Public Health England (PHE) shows this vaccine is 96% effective against hospitalisation with severe illness due to the Delta variant after two doses.

PHE said: “These findings indicate very high levels of protection against hospitalisation with the Delta variant with one or two doses of either vaccine (Pfizer or AstraZeneca).

Moderna:

Can be given to over 18s at GPs and mass vaccination centres. It can also be given to pregnant women. 

Real-world data published in June by the Centres for Disease Control in America shows that after two doses of this vaccine, the recipient is 91% effective at preventing severe infection. 

On Thursday, the company published results confirming a "neutralising" effect against Delta.