Health experts are raising the alarm as the UK potentially faces its most severe flu season in decades, driven by the early and aggressive spread of the H3N2 strain.
Why This Flu Season is Different
The H3N2 flu strain is currently the most dominant circulating in England. Cases have surged much earlier this winter than is typical, with hospitalisation rates already reaching levels normally not seen until December. This pattern mirrors the recent experience in Australia, which endured its largest flu season on record.
Data from the UK Health Security Agency (UKHSA) shows the rate of hospital admissions for flu in England has risen to 3.8 per 100,000 people. This early spike is a significant cause for concern among public health officials.
A Mutated Virus and Its Impact
A key reason for the heightened concern is the virus's ability to change. Over the summer, the H3N2 strain developed seven new mutations. This means the current dominant version is substantially different from both previous circulating strains and even the strain included in this year's flu vaccine.
This regular mutation can mean people have less built-up immunity, potentially leading to more widespread illness. The H3N2 strain can sometimes cause a more severe illness, particularly in older adults and individuals with underlying health conditions.
Recognising Symptoms and Protecting Yourself
Symptoms for the H3N2 flu are similar to other flu strains and come on abruptly, unlike a cold which develops gradually. According to the NHS, key symptoms include:
- A sudden high temperature
- An aching body
- Feeling tired or exhausted
- A dry cough
- A sore throat and headache
Children may exhibit similar signs but could also be less active and complain of ear pain.
The most effective defence remains getting the flu jab, especially for those in high-risk groups. While the vaccine may not ward off every strain due to the mutations, it is proven to significantly reduce the severity of the illness and the risk of hospitalisation.
High-risk groups urged to get vaccinated include:
- People aged 65 and over
- Pregnant women
- Those with long-term heart, lung, kidney, brain or nerve conditions
- Individuals with weakened immune systems
Anyone in these categories who develops flu symptoms is strongly advised to contact their GP or seek help via NHS 111. This also applies to anyone whose symptoms do not improve after seven days.
