As flu season gets under way, doctors are urging people to learn how to distinguish between a common cold and influenza -- two illnesses that are often confused but carry very different risks, according to a report by The Independent.
Early data from the UK Health Security Agency shows hospital admissions in September have already outpaced the same period over the last four years, with 18- to 24-year-olds driving the spike.
While both illnesses spread through respiratory droplets and contact with contaminated surfaces, their symptoms set them apart.
A cold typically brings a runny nose, sore throat and mild fatigue, developing gradually over a day or two. Flu, by contrast, strikes suddenly -- with high fever, severe exhaustion, muscle aches and chills.
“The key difference is that flu tends to come on suddenly and much more severely, whereas cold symptoms are milder and develop more gradually,” Dr Claire Agathou, GP and co-founder of the A–Z General Practice at The Wellington Hospital, part of HCA Healthcare UK, told The Independent.
Flu also carries greater risks. While colds are generally mild and self-limiting, influenza can lead to pneumonia, hospitalisation, and serious complications -- even in otherwise healthy people, Dr Agathou warned.
“Even those who are normally well can become very unwell, so it’s important to contact your GP promptly if you feel unwell or are concerned about your symptoms,” she said.
Both illnesses are caused by different viruses -- colds most commonly by rhinovirus, flu by influenza types A and B -- meaning it is possible to be infected with both simultaneously, said Dr Naveed Asif, GP at The London General Practice, also speaking to The Independent.
Treatment for both centres on rest, fluids and paracetamol.
Antiviral medication may be prescribed for flu in high-risk patients if caught early, but antibiotics are ineffective unless a secondary bacterial infection develops, Dr Agathou said.
Recovery from a cold usually takes up to 10 days; flu can sideline a person for two weeks or longer.
The most effective protection against flu remains the annual vaccine, available free on the NHS to eligible groups including adults over 65, pregnant women, children aged two to three, school-aged children up to Year 11, and those with certain long-term conditions. Others can access it privately, Dr Agathou added.