FACTORS CONTRIBUTING TO EARLY SEASONAL SURGE OF INFLUENZA CASES AND PREVENTION STRATEGIES

NOTICE PAPER NO. 242

NOTICE OF QUESTION FOR WRITTEN ANSWER

FOR THE SITTING OF PARLIAMENT ON OR AFTER 5 NOVEMBER 2025

Name and Constituency of Member of Parliament

Mr Gabriel Lam

MP for Sembawang GRC

Question No. 601

To ask the Coordinating Minister for Social Policies and Minister for Health (a) what factors contributed to the early seasonal surge in influenza cases since August 2025; (b) how the Communicable Diseases Agency is strengthening surveillance and vaccination outreach ahead of future off-season spikes; and (c) whether climate trends or travel patterns are influencing Singapore’s influenza transmission cycles.

Answer

1         In Singapore, influenza viruses circulate throughout the year, with two periods of higher activity typically observed between May and August and between December and March. These broadly coincide with the Northern and Southern Hemisphere winter seasons, but their timing may vary from year to year due to factors such as international travel, weather conditions, immunity levels and population mixing patterns. The increase in influenza activity since August 2025 illustrates this variability. There is no evidence of any significant new trends that are fundamentally changing Singapore's influenza transmission cycles.

2         The Communicable Diseases Agency has surveillance programmes that monitor the incidence of influenza and other acute respiratory infections at selected primary care clinics as well as acute hospitals. These are continually enhanced to strengthen surveillance and response capabilities so that we can detect surges and respond to them as necessary.

3         Under the National Childhood Immunisation Schedule (NCIS) and National Adult Immunisation Schedule (NAIS), vulnerable groups are recommended to receive annual or per-season influenza vaccination. Vaccination is available at any time of the year, and medical practitioners receive bi-annual clinical guidance on administering the vaccine for each season. Individuals should receive the vaccine when they are due to do so, as influenza transmits year-round. They may consult their doctors to discuss their need and timing in receiving the vaccine, based on individual circumstances.