Effective Antibody testing is now available and plans are being developed for its use in Northern Ireland. Our antibody testing programme will provide information on the prevalence of COVID-19 among different age groups and settings in Northern Ireland and will improve our understanding of how the disease spreads.
This will work alongside existing PCR (swab) testing which confirms whether or not someone currently has the SARS-CoV-2 virus.
It is important to acknowledge at the outset that there is considerable uncertainty about the significance of a positive test result for antibodies. While it means than an individual has had COVID-19 at some time in the past it does not indicate that the individual cannot be re-infected with the virus, or would not pass it on to others, or have protective immunity. All infection prevention and control measures including the use social distancing and PPE (as appropriate) must continue to be in place irrespective of the presence of antibodies.
The test is a venous blood test and analysis can be undertaken on existing analysers in all HSC Trust laboratories in Northern Ireland. In view of the uncertainty about the significance of antibody testing, the approach to antibody testing over the next few months will be to offer testing to health and care workers in hospital and the community (including independent contractors) as part of a seroprevalence study. This work may require investment in additional trained phlebotomy staff.
The Belfast Trust will pilot the approach to antibody testing including the development of information materials, obtaining consent, data collection, laboratory testing, communication of results, data analysis and inclusion of results in the Northern Ireland Electronic Care Record. After the logistics have been tested and revised following the pilot, other HSC Trusts will be expected to adopt similar approaches so that we can get a comprehensive picture of the impact of COVID 19 on health and care workers in Northern Ireland. No decision has been made regarding repeat testing at this stage
The approach to patient testing is still being developed. There is an expectation that this will also follow a seroprevalence approach, to allow us to assess the impact of COVID 19 in different patient groups. In the interim, if an antibody test is deemed essential to assist with individual patient care, that may be arranged on a case by case basis (e. g. clinical picture consistent with COVID but swab negative) providing an agreed clinical dataset is collected at that time the sample is obtained. The antibody test should not be used to guide patient flow decisions.
Research and the General Population
Antibody testing is also part of a UK-wide study in which the Office for National Statistics will undertake of a sample of c10% of households in Northern Ireland. Detailed planning is already underway for this study which we expect will be introduced in the coming months. We also hope to participate in four country research studies using antibody testing which are currently in planning. This is a rapidly changing area of clinical practice and it is important that we use antibody testing effectively to inform our pandemic response. I will write to you again when plans have been finalised for the introduction of patient testing.