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  • Coronavirus (Covid-19) Infection Survey – Antibody and Vaccination Data for Northern Ireland

    Date published: 28 April 2021

    The Department of Health today published a report on antibody and vaccination data from the COVID-19 Infection Survey (CIS).

    covid latest stats

    The findings set out in this report relate to modelled antibody estimates for Northern Ireland for the week up to the 11 April 2021 and modelled vaccination estimates up to the 16 April 2021.

    This report is part of the series of Northern Ireland publications from the COVID-19 Infection Survey. Further information can be found on the Department of Health website.

    Key Findings

    Due to the relatively small number of people who tested positive for antibodies within our sample, credible intervals are wide and therefore results should be interpreted with caution.

    • In Northern Ireland, an estimated 6 in 10 adults, or 62.5% of the adult population (95% credible interval: 56.4% to 70.9%) would have tested positive for antibodies against SARS-CoV-2 on a blood test in the week ending 11 April 2021, suggesting they had the infection in the past or have been vaccinated.
    • The percentage of adults aged 70 years and over testing positive for antibodies was 82.0% (95% credible interval: 69.2% to 91.3%) in the week ending 11 April 2021. The percentage of adults testing positive for antibodies in the other age groups ranged from 36.0% to 79.5%.
    • The survey provides an estimate of the percentage of people that have been vaccinated however it should be noted that the figures are based on self-report and may differ from figures produced from administrative sources.
    • The survey estimates will allow for additional analysis of vaccination information with other characteristics, such as testing positive for antibodies.
    • The survey shows that in Northern Ireland, an estimated 69.9% (95% credible interval: 68.3% to 71.3%) of the adult population have been vaccinated (at least one dose) against SARS-CoV-2 in the week ending 16 April 2021.
    • In the week ending 16 April 2021, the survey shows the percentage of people who have been vaccinated against SARS-CoV-2 for those aged 70 years and over was 97.7% (95% credible interval: 96.1% to 98.6%). The percentage in the other age groups ranged from 15.4% to 94.2%.
    • The survey suggests an estimated 23.3% (95% credible interval: 21.6% to 25.1%) of adults have been fully vaccinated.

    Notes to editors:

    1. The Department of Health has been working along with the Public Health Agency, Northern Ireland Statistics and Research Agency and the Office for National Statistics (and its various survey partners) to extend the COVID-19 Infection Survey to Northern Ireland. Fieldwork in Northern Ireland began on 27 July 2020.
    2. All results are provisional and subject to revision. Due to the relatively small number of people who tested positive for antibodies within our sample, credible intervals are wide and therefore results should be interpreted with caution.
    3. These statistics refer to the presence of antibodies to the Coronavirus (COVID-19) and vaccinations within the community population, by which we mean private residential households. These figures exclude those in hospitals, care homes and/or other institutional settings.
    1. This report is part of the series of Northern Ireland publications from the COVID-19 Infection Survey. Positivity estimates are published on a weekly basis and antibody/vaccination data fortnightly. Further information can be found on the Department of Health website.
    1. Further information about quality and methodology associated with the survey can be found on the ONS website: www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/conditionsanddiseases/methodologies/covid19infectionsurveypilotmethodsandfurtherinformation#covid-19-infection-survey
    1. This publication is available on the Department's website.
    1. Additional information is available from:

    Information Analysis Directorate
    Department of Health
    Annex 2, Castle Buildings
    Stormont
    Belfast BT4 3SQ
    Telephone: 028 9052 2340
    E-mail: statistics@health-ni.gov.uk

    1. For media enquiries please contact DoH Press Office by email: pressoffice@health-ni.gov.uk. 
    2. Follow us on twitter @healthdpt.
    3. The Executive Information Service operates an out of hours service for media enquiries only between 1800hrs and 0800hrs Monday to Friday and at weekends and public holidays. The duty press officer can be contacted on 028 9037 8110.

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