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Background Notes

The average monthly increase in COVID-19 additional dose 2 vaccines was 4.5% in May 2022.

CSO statistical release, , 11am
A CSO Frontier Series Output

This publication is categorised as a CSO Frontier Series Output. Particular care must be taken when interpreting the statistics in this release as it may use new methods which are under development and/or data sources which may be incomplete, for example new administrative data sources. 

This publication is based on vaccinations administered up to 31 May 2022. It is the fifth publication by the Central Statistics Office (CSO) providing insights into Ireland's COVID-19 vaccination programme (COVID-19 Insight Bulletins: ICU and Hospital Admissions Series 1COVID-19 Vaccination Statistics Series 1COVID-19 Vaccination Statistics Series 2, COVID-19 Deaths and Cases, Series 32). This report is produced in collaboration with the Health Protection Surveillance Centre and Department of Health under the Statistics Act, 1993. The vaccination dataset used is provided to the CSO by the Health Service Executive (HSE).

Data Sources

For vaccination rates, the CSO uses data provided by COVAX (the HSE national immunisation registry for COVID-19 vaccination). Data were extracted from COVAX on 09/06/2022 and were correct at the time.

Additional demographic and employment information was derived by linking to Revenue PAYE Modernisation system (PMOD) and the Department of Social Protection (DSP) Central Records system (CRS) using pseudonymised identifiers.

Please see Vaccination Data FAQ for further information.

Local Electoral Areas (LEA) assignment

LEAs are assigned through geocoding of addresses undertaken within the CSO (including using Eircodes provided in the COVAX dataset).

Vaccination Rates 

Fully vaccinated populations were defined as those who had a single valid dosage date record for a single-dose vaccine or two valid dosage dates for double dose vaccines recorded on Covax.

Additional dose vaccinations were defined as those individuals who had valid third / fourth / fifth dosage date entries for either the immuno-compromised or additional doses.

In this release, the following definitions apply: 

  • Fully Vaccinated - Those who had a single-dose vaccine or double dose vaccines. 
  • Additional Dose 1 - Those who are fully vaccinated and have received their first booster vaccine (including immunocomprimised dose).
  • Additional Dose 2 - Those who are fully vaccinated and have received a first additional dose and their second booster vaccine (including immunocomprimised dose). 

The vaccination rates should be interpreted as estimates. For example, the number of persons who have received a vaccine only includes those who have been vaccinated in the State and would not include those who may have been vaccinated outside of the State. Further, the denominators are based on population estimates. As rates are estimates, this may lead to an underrepresentation or overrepresentation of the vaccination rates for a given grouping or LEA.

Data included in the corresponding PxStat tables to this bulletin (CDC45) is rounded in line with Statistical Disclosure Control (SDC) procedures.

Why you can Trust the CSO

Learn about our data and confidentiality safeguards, and the steps we take to produce statistics that can be trusted by all.