Published on 

Deputy Chief Medical Officer at the Department of Health Dr Ronan Glynn

In recent weeks we have seen increased commentary, both nationally and internationally, relating to infections in people who have been fully vaccinated. It is important when analysing these data that they are placed in the context of the proportion of the whole population who have been vaccinated.  

Uptake of vaccination has been remarkably high in Ireland and continues to increase. As vaccination rates increase, there will be more vaccinated and fewer unvaccinated people in the population. As a result, the proportion of cases in vaccinated people will increase. For example, if all of the population were to get vaccinated then, clearly, 100% of COVID-19 cases would be in those who had been vaccinated. This does not mean that vaccines are not working.

A good way to think about this is in relation to road safety – the majority of people who die on our roads are wearing a safety belt. This does not mean that safety belts do not work. It simply reflects the fact that the vast majority of people wear safety belts when driving and, unfortunately, some will be involved in accidents. However, for each individual, the risk of a severe injury or dying in that accident is much lower if they are wearing a safety belt.  

While the proportion of cases in vaccinated people will increase, we can be very confident that the absolute number of cases in vaccinated people will decrease over time. We have already seen this in older age groups. For example, while 67% of cases in those who are 65 years and older in the last fortnight have been in people who reported having received two vaccines, the absolute number of cases in this age group (764) is much less than in previous ‘waves’. A similar disease profile last February, for example, resulted in 3,379 cases over a two-week period in the same age group. 

When we see cases in vaccinated people, we need to remember what we are not seeing. What we don’t see is the very many more infections, hospitalisations and deaths that have been prevented by vaccination.

Of course, no vaccine is 100% protective and some people who have been fully vaccinated will still get infected with, and get sick from, COVID-19. However, the individual risk of a severe illness or death is much lower than if they had not been vaccinated. This is reflected in our ICU and mortality data. Of 169 adults admitted to ICU with COVID-19 since 1st April just 6 had been fully vaccinated more than 14 days prior to their diagnosis. Of 155 adults who have died with COVID-19 since 1st April just 7 had been fully vaccinated more than 14 days prior to their diagnosis.  

Vaccines work. They are about 80% effective at preventing symptomatic COVID-19 disease and they provide approximately 95% protection against hospitalisation – and this protection against severe disease holds up even in the context of the Delta variant.

The COVID-19 vaccination programme has shown not only the best of scientific and medical endeavour, but also commendable solidarity by those who have come forward to receive a vaccine for the good of themselves and their wider community. Of course, while uptake has been fantastic, there are many who have not yet taken the opportunity to get protected through vaccination. For those who remain unsure, have questions or concerns, please access information through your GP or pharmacist, look at the information available on hse.ie or ask questions at HSELive.

ENDS