Written by Dr Zamiel Hussain, Lead GP and Founder of AccessGP
Flu is circulating at higher than expected levels this winter, with national surveillance showing a sharp rise in cases earlier than usual. This appears linked to changes in dominant flu strains, reduced population immunity and the natural seasonal peak arriving slightly ahead of schedule.
Many people are experiencing more severe symptoms than in previous years, along with faster household transmission. This guide explains what flu looks like this season, why this year is different, when antiviral treatment is useful and when to seek GP support.
Why flu is worse this year
Every winter brings some level of flu, but this season is notable for three reasons:
1. A shift in the dominant circulating strain
National data shows increased activity of a subtype of influenza A (commonly H3N2), which tends to cause more severe illness in older adults and people with chronic conditions. Mutations in the circulating strain can reduce background immunity, leading to higher symptom burden.
2. Lower immunity following milder recent seasons
The last two flu seasons were relatively quiet due to widespread COVID measures. Reduced exposure means population immunity is lower this year, making infections more likely and symptoms more noticeable.
3. High levels of other winter viruses at the same time
RSV, adenovirus and COVID are also circulating. Co-infection can worsen symptoms and prolong recovery, especially in vulnerable groups.
Flu symptoms this season
Symptoms are developing quickly in many patients this year. Typical signs include:
- Sudden high fever
- Muscle and body aches
- Headache
- Sore throat
- Dry cough
- Feeling exhausted or unable to get out of bed
- Loss of appetite
- Chills and sweats
Children may also develop tummy pain, vomiting or earache.
Flu symptoms usually peak between day two and day four, with gradual improvement over a week.
When flu becomes more serious
You should seek medical advice promptly if you or your child has:
- Shortness of breath or rapid breathing
- Chest pain
- Fever lasting more than three days
- Severe dehydration or reduced urine output
- Confusion, drowsiness or new disorientation
- Symptoms improving but then worsening again
- Very high fever not responding to simple medication
- A long term condition such as asthma, COPD, heart disease, diabetes or a weakened immune system
Small children, pregnant women and adults over 65 are at higher risk of complications and should seek advice early.
Are antiviral medications useful?
Yes, in certain situations, but they must be prescribed safely and at the correct time.
The two main licensed antivirals in the UK are:
1. Oseltamivir (Tamiflu)
- Taken as a capsule or liquid
- Most effective when started within 48 hours of symptom onset
- Can be prescribed to:
- High risk patients with confirmed or suspected flu
- People who are severely unwell
- Certain exposed individuals in care home outbreaks or vulnerable settings
- Helps shorten illness and reduce complications
2. Zanamivir (Relenza)
- Inhaled antiviral
- Used when oseltamivir is not suitable, especially in some resistant strains
- Often used in hospital or specialist settings
- Not commonly prescribed in primary care unless clinically indicated
Who is NOT usually given antivirals?
- Healthy adults with mild to moderate flu
- Those presenting after 48 hours, unless severely unwell or high risk
- People outside the NICE-defined risk groups
Antivirals are not cure-alls and do not eliminate symptoms instantly. They reduce the severity and duration of illness, and are most beneficial in high risk groups.
Should you still get a flu vaccine now?
Yes. Even during a peak season, the vaccine:
- Reduces the severity of illness
- Lowers the risk of hospitalisation
- Protects vulnerable family members
- Helps prevent co-infection with other winter viruses
The strain change this year makes vaccination even more relevant, especially if you have not yet had your flu jab.
How AccessGP can help this winter
At AccessGP we can:
- Assess your symptoms via same day online GP appointments
- Identify whether flu, COVID or another infection is likely
- Advise when antivirals are appropriate and prescribe them when clinically indicated
- Provide safety netting advice tailored to your risk level
- Recommend practical home management steps
- Direct you to urgent care if symptoms warrant escalation
We also link directly to our Knowledge Base, where you can learn more about winter infections, fever management and blood tests that may be relevant during prolonged illness.
When to seek urgent help
Call 999 or attend emergency care if there is:
- Severe breathlessness
- Blue lips, cold hands or feet
- Severe chest pain
- Seizures
- Unresponsiveness
- A child who is floppy, non-responsive or not drinking
Key sources: AccessGP Clinical Knowledge Base; UKHSA Weekly Influenza Surveillance; NICE TA168, Oseltamivir and Zanamivir; NHS UK, Flu Overview; Patient.info, Seasonal Flu.