Flu Season Peaks Early in December 2025 Amid NHS Crisis and Vaccine Challenges
In December 2025, the UK experienced a surge in flu cases, with around 2,660 hospital admissions per day for influenza, marking a record for this time of year and a 55% weekly increase. Emergency department attendances for flu and respiratory illnesses also reached record levels. The circulating flu strains included H1N1, H3N2, and influenza B. Notably, a new H3N2 subvariant called K emerged late in the season and was poorly matched by the current vaccine.
Despite this mismatch, real-world vaccine effectiveness remained significant, estimated at approximately 72–75% against emergency department attendance and hospital admission in children and adolescents, and 32–39% in adults. Vaccine uptake revealed suboptimal coverage, with about 40% uptake among at-risk groups under 65 years old, 42.6% for 2–3-year-olds, and around 74.9% for those aged 65 and above.
The private market faced vaccine shortages, with many pharmacies reporting low or no stock, while vaccination costs of approximately £18–£20 per dose posed barriers for some individuals. Concurrently, the NHS was under severe pressure due to limited surge capacity and hospitals nearing full occupancy, sparking concerns over the demand expected in January and February.
The term 'super flu' appeared in communications from NHS England officials and politicians but is not a scientific term recognized by academics or clinicians. Despite the challenges, health experts emphasize that vaccination remains beneficial even with imperfect protection. It is encouraged that individuals seek vaccination through local pharmacies or vaccination sites to reduce the risk of severe outcomes as the flu season progresses.
