The Moving Epidemic Method (MEM) is the ECDC/WHO-Europe-endorsed approach for establishing influenza epidemic thresholds and intensity levels, yet no positivity-based MEM analysis exists for Türkiye or any country in the WHO Western Asia transmission zone. Weekly influenza positivity rates from FluNet sentinel surveillance were analysed for ten of twelve seasons (2013/2014–2024/2025, excluding two COVID-19 pandemic seasons) using the mem R package with cross-validated optimized slope parameter, and Türkiye’s average epidemic curve and thresholds were compared with the Western Asia (excluding Türkiye) and South West Europe zones using Lin’s concordance correlation coefficient (CCC), root mean square deviation (RMSD) and complementary correlation metrics. The epidemic threshold was 10.59% positivity, with intensity thresholds at 42.56% (medium), 60.92% (high), and 71.38% (very high); cross-validated sensitivity was 0.77, specificity 0.88, and Matthews correlation coefficient 0.65. Türkiye’s average curve showed higher concordance with Western Asia (CCC=0.890; RMSD=4.22 percentage points) than South West Europe (CCC=0.672; RMSD=12.48) despite similar Pearson correlations (0.922 vs. 0.939), and the Western Asia epidemic threshold (11.50%) closely matched Türkiye’s. These first operational MEM thresholds for Türkiye and the first positivity-based thresholds for the Western Asia zone confirm alignment with the current WHO transmission zone classification and support integration into routine surveillance.

Influenza and respiratory syncytial virus (RSV) are common causes of respiratory tract infections and place a burden on health services each winter. Systems to describe the timing and intensity of such activity will improve the public health response and deployment of interventions to these pressures. Here we develop early warning and activity intensity thresholds for monitoring influenza and RSV using two novel data sources: general practitioner out-of-hours consultations (GP OOH) and telehealth calls (NHS 111). Moving Epidemic Method (MEM) thresholds were developed for winter 2017–2018. The NHS 111 cold/flu threshold was breached several weeks in advance of other systems. The NHS 111 RSV epidemic threshold was breached in week 41, in advance of RSV laboratory reporting. Combining the use of MEM thresholds with daily monitoring of NHS 111 and GP OOH syndromic surveillance systems provides the potential to alert to threshold breaches in real-time. An advantage of using thresholds across different health systems is the ability to capture a range of healthcare-seeking behaviour, which may reflect differences in disease severity. This study also provides a quantifiable measure of seasonal RSV activity, which contributes to our understanding of RSV activity in advance of the potential introduction of new RSV vaccines.