Influenza A(H3N2) early season activity in England: implications for clinical practice and laboratory referral – Briefing Note 2025/042

Dear colleagues,

The latest UKHSA surveillance data shows influenza activity is now above baseline levels following an early start to influenza circulation in children and young adults. We anticipate that circulation will continue to increase and spread in these and in other age groups. All eligible groups should be encouraged to get vaccinated with the 2025 to 2026 seasonal influenza vaccine as soon as possible.

Antivirals guidance for treatment and prophylaxis of seasonal influenza has been updated – health professionals should familiarise themselves with the key updates, which simplify first line recommendations, strengthen advice to support empirical treatment with neuraminidase inhibitors and diagnostic testing, and advise on the use of baloxavir marboxil.

If you have any queries, please see: https://www.gov.uk/guidance/contacts-phe-health-protection-teams