At present real-time reverse transcription polymerase chain reaction (RT-PCR) is the gold standard for diagnosing suspected cases of COVID-19. There is no role for using this test as an indication of past infection. It can only detect whether there is active virus present at the time of the test.
However serological testing can be used to estimate the level of past exposure and immunity in the general population. Estimation of population age-specific immunity or past exposure to SARS-CoV-2 is one of the actions in Ireland’s National Action Plan in response to COVID-19.
Following a request from the National Public Health Emergency Team (NPHET) the HSE and Health Protection Surveillance Centre (HPSC) are proceeding with plans to undertake a population sero-prevalence study. This work is being carried out jointly by HPSC and NVRL, in collaboration with the Central Statistics Office and Department of Health.
I understand that it is intended that an application to the National COVID-19 Research Ethics Committee will be submitted shortly and that subject to ethics approval and completion of clinical validation of a suitable assay (i.e. antibody test) the aim is to start the seroprevalence study in the next 4 weeks.