Before the full implementation of the National Serosurveillance Programme (NSP), a pilot phase was carried out to test the processes of the proposed surveillance system. A surveillance report, available below, was also produced using laboratory results from the pilot.
The purpose of the pilot was to test each step of the NSP process, from collection of the residual sample in the lab, to public reporting of the seroprevalence result. Results from an evaluation of the pilot were used to inform the decision to go ahead and start the NSP, and helped identify minor changes in processes.
This involved several months of groundwork with participating laboratories prior to the pilot. The pilot itself took place in October 2021 and eight hospital laboratories throughout Ireland participated. Over a one-week period, each laboratory was asked to collect 100 residual blood samples in the laboratory that had come from general practice. The samples were then anonymised within the laboratory prior to dispatch, given a unique ID and sent to the National Virus Reference Laboratory (NVRL). NVRL tested the samples for COVID-19 antibodies and sent the results to the Seroepidemiology Unit (SEU) in the HPSC to produce a surveillance report.
In all, 791 samples were submitted to NVRL for testing. The results of 787 were included for analysis. The adjusted seropositivity rate was 91.7%. The evaluation of the pilot identified some challenges for the laboratories, most notably the staffing resources required for the work due to the time-intensive nature of ensuring that the specimen were anonymised. Overall however the pilot successfully showed that surveillance using residual laboratory-based blood samples from general practice is a cost effective and viable alternative to population based seroprevalence studies.
Read the pilot study surveillance report in full below: