An evaluation of the severe acute respiratory infection (SARI) surveillance system in Ireland

BACKGROUND: Expansion of the current single hospital site Severe Acute Respiratory Infection (SARI) surveillance programme in Ireland, to create a sentinel network, will commence in 2023. This evaluation aimed to assess the performance of key surveillance system attributes to improve and guide expansion. METHODS: A mixed quantitative and qualitative evaluation was conducted from September 2021 to November 2022. SARI surveillance data were analysed to assess completeness, timeliness and positive predictive value (PPV). An online stakeholder questionnaire, semi-structured focus group discussions and key informant interviews evaluated usefulness, simplicity, flexibility and acceptability. Qualitative data were analysed using thematic analysis. RESULTS: Among SARI cases (n = 747), completeness of key variables including age, sex and outcome was 100%. Symptom data were completed in > 90%, COVID-19 vaccination status was completed in 89% and completeness of ethnicity data was 0.6%. Median times from hospitalisation to data entry commencement and completion were one day (IQR 1-3) and 48 days (IQR 21-81) respectively. Time to receipt of whole genome sequencing (WGS) results was 40 days (IQR 30-61). PPV was 95% (95% CI 93%-97%). The questionnaire response rate was 21% (75/362) and 96% (72/75) agreed that SARI surveillance is important. Key themes identified in the qualitative study (n = 11) were the complexity and importance of SARI surveillance. Suggested areas for improvement included process automation and additional designated resources to improve timeliness, flexibility and acceptability; particularly during epidemic or pandemic surge periods. CONCLUSIONS: The SARI surveillance system reports high-quality data. Timeliness of WGS data and recording of vaccination status and equity stratifiers e.g., ethnicity should be improved. Priorities for expansion should be automation and adequate resource allocation to enable reliable SARI surveillance at all times. KEY MESSAGES: • The SARI surveillance system is a resource intensive, complex system that is an important component of national surveillance in Ireland and reports high-quality and timely surveillance data. • The priorities for expansion are process automation where possible and ensuring adequate resources, specifically skilled staff. These evaluation findings should inform SARI expansion in Ireland.