FOI/2021/2734
You asked
Please supply the following information:
How you assess the percentage of people with antibodies?
What test is used to test for antibodies?
What sources are used specifically to to assess the percentage of people with antibodies?
Are there links to the raw data?
Do you produce the data about side effects of the vaccines? If so where, and if not what are the reasons?
We said
Thank you for your request.
The COVID-19 Infection Survey is a household survey that estimates the number of people testing positive for infection and for antibodies in the UK. Our statistics refer to individuals in the community, by which we mean private households. These figures exclude infections reported in hospitals, care homes or other institutional settings.
To capture data about people with antibodies, we ask adults aged 16 years or older from 20% of enrolled households to give a sample of blood, whereby 0.5 millilitres venous blood will be drawn using a capillary finger prick method undertaken by the participant and demonstrated by a specially trained fieldworker. The blood samples are taken at enrolment and then every month.
Blood samples are tested for antibodies using an assay for IgG immunoglobins against the spike (S) protein, which are produced to fight the virus, irrespective of symptoms. From March 2021, we also test samples for IgG immunoglobulins against the nucleocapsid (N) protein as well. More information on the methods around this antibody assay can be found in a study comparing its performance with four other assays.
Further information on our sample and method for antibody analysis can be found in our methods article and study protocol.
We do not publish raw data, however you can find our antibody estimates in the dataset accompanying our antibody and vaccination article.
We do not collect data on vaccine side effects. Public Health England or NHS Digital may be better placed to assist with this query. They can be contacted via email at wn_coronavirus@phe.gov.uk and enquiries@nhsdigital.nhs.uk respectively.
For further information and an overview of all the data published across the ONS, please check our ONS COVID Insights Tool.