Respiratory Viruses Surveillance Bulletin: Epidemiological Week 21, 2026

Overview

• Regional influenza positivity remained stable and is at 9% in week 21 of 2026.  SARS-CoV-2 positivity remained below 5% in the Region (Figure 1).
• An increasing trend in both influenza and SARS-CoV-2 positivity was observed in Singapore in the past few weeks, with positivity for both at 17% on week 21 (Figure 5). Singaporean authorities have also noted in their press release a recent increase in COVID-19 cases and called for public vigilance (Source).
• The predominant circulating influenza subtype is influenza B(Victoria), accounting for 90.4% of all detections (Figure 2).