Seroepidemiology of COVID-19 data hub launched


The HPSC Seroepidemiology Unit (SEU) is pleased to announce the launch of the HPSC Seroepidemiology of COVID-19 Data Hub.

The hub presents a summary of COVID-19 seroprevalence due to vaccination or infection in Ireland over time, by age and quantitative antibody levels. It is a collaborative project between HPSC SEU, Irish Blood Transfusion Service (IBTS) and staff seconded from National University of Ireland Maynooth.

To access the HPSC Seroepidemiology of COVID-19 Data Hub, please visit

The dashboard provides data on trends in overall seroprevalence (the proportion with antibodies to COVID-19) and seroprevalence due to infection or vaccination in blood donors aged 20-79 years, from Dublin and Cork, since 17 October, 2021. Trends in seroprevalence are available from October, 2021 to 24 June, 2022.

Here are some of the key points the data are currently showing:

  • Overall seroprevalence is currently 99% among blood donors
  • Seroprevalence indicating infection is relatively high at 69% for all ages
    • 87% in 20-29-year olds
    • 71% in 30-49-year olds
    • 60% in 50-79-year olds
  • This means that, for example, 87% of young blood donors (20-29 yrs.) have evidence of natural infection with COVID-19 at some time, indicating a high level of transmission in the population. It is hard to compare these findings with other surveillance data, as testing policy changed considerably in recent months. These data are not affected by testing policy or health seeking behaviour
  • It is not possible to identify re-infections in these data. The presence of antibodies in a participant’s blood is a sign that they were infected with the COVID-19 virus at some time in the past.
  • There is no threshold antibody level that offers complete protection against infection, but higher antibody levels are likely to be associated with a lower probability of infection
    • Median overall antibody levels in blood donors aged 20-59 years have plateaued or decreased since peaking in mid to late January, whereas antibody levels in individuals aged 60-79 started to increase again in late April, likely due to the second COVID-19 booster vaccination campaign for those aged over 65 years
    • For individuals (all age groups) with evidence of antibodies due to vaccination only, median antibody levels peaked in late January and have declined since.

This is the first iteration of the hub and the SEU Team plan to present data from its acute laboratory partners, the Laboratory Serosurveillance Network (LSN), in the near future.

Previous IBTS and LSN surveillance reports are available here.

To view the HPSC Seroepidemiology of COVID-19 Data Hub, please visit