A partnership approach to rapidly establishing COVID-19 surveillance during the pandemic

A collaboration between Welsh Blood Service, Public Health Wales, Swansea Bay UHB and Cwm Taf Morgannwg UHB

At the start of the pandemic, surveillance of COVID-19 focused on counting cases, hospitalisations, and deaths. This did not provide a true measure of the number of people infected, since a proportion of the population with mild and asymptomatic infection were missed. A knowledge gap on immunity levels to the COVID-19 virus in the Welsh population was hampering policy decisions on public health interventions.

A collaboration project between Welsh Blood Service (WBS), Public Health Wales (PHW), Swansea Bay UHB and Cwm Taf Morgannwg UHB aimed to fill this gap by establishing a scientifically robust surveillance system to measure two distinct antibodies against the COVID-19 virus within a Welsh population. Antibody status monitoring allowed estimation of natural infection and vaccination rates.

Each day, an average of 100 donor samples from WBS donors are sent for testing. University Health Board laboratories test to measure the natural and vaccine-mediated COVID-19 antibody levels. These results are sent to PHW, along with demographic data from WBS, for epidemiological analysis. From this, a report is produced showing a month-on-month picture of COVID-19 immunity levels in the Welsh population. This includes a breakdown of immunity levels in different age groups and regions within Wales.

The project uses a combination of specialist and scientific expertise from many disciplines: epidemiology, biochemistry, virology, serology, and blood transfusion sciences. The different skill sets and facilities each organisation has to offer are recognised and utilised, and has helped to build new bridges across organisations.

The reports produced from the project have contributed to the health and wellbeing of the Welsh population by providing invaluable information for action on a national and local level, informing decisions regarding COVID-19 vaccination programmes. Data on waning immunity will assist in policy decisions on the timing of future booster vaccinations.

Courtney Morris

wbs.research@wales.nhs.uk