Data sources on COVID-19 infection and vaccination in pregnancy on the island of Ireland: strengths, weaknesses, and recommendations for future pandemic preparedness

Background: Monitoring coronavirus disease (COVID-19) infection and vaccination during pregnancy is vital because of the increased susceptibility to severe disease. This article outlines the available data sources on COVID-19 infection and vaccination rates during pregnancy in Northern Ireland (NI) and the Republic of Ireland (ROI) and describes the processes, strengths, and weaknesses of available data. Methods: Three data sources on COVID-19 vaccination and infection were identified in the ROI: the national computerized infectious disease reporting (CIDR) system used for reporting notifiable infectious diseases, the national dataset of all COVID-19 vaccinations for all residents (COVAX), and a regional Maternal and Newborn Clinical Management System (MN-CMS), which includes data on COVID-19 vaccination and infection. Four data sources were identified in NI: the NI maternity system (NIMATS) records maternity data, including COVID-19 infection and vaccination during pregnancy; datasets of COVID-19 antigen testing performed in hospitals (Pillar 1) and in the community (Pillar 2); and the NI Vaccine Management System dataset of COVID-19 Vaccinations. Results: In the ROI, the CIDR database allows for the calculation of COVID-19 infection rates in women of reproductive age; however, pregnancy status remains largely unreported. The COVAX dataset includes pregnancy status, although the accuracy depends on whether the pregnancy is known at the time of vaccination. The MN-CMS tracks COVID-19 infection and vaccination during pregnancy. However, there are uncertainties regarding its reliability. In NI, COVID-19 data are available for all pregnant women using Health and Care numbers to link the NIMATS data to testing and vaccination databases. Conclusions: Both countries track COVID-19 infection and vaccination rates, but the strength of the NI system is the use of unique identification numbers that allow linkage of maternal records to infection and vaccination databases. Both countries face delays in data access, underscoring the need for real-time systems to support future pandemic preparedness.