UNSURE whether you’ve been affected by the flu or a cold? A doctor has identified an ‘overwhelming’ symptom that indicates the ‘superflu’ could be the cause.

This comes as the UK faces an earlier-than-usual spike in flu cases this season.

Illustration of Influenza virusesA mutated strain of flu is contributing to the increase in casesCredit: Getty Sick woman looking at thermometer while sitting on the sofa.A doctor has shared key distinctions between colds and fluCredit: Getty

Last week, an average of 2,660 patients were hospitalized daily due to the virus—the highest number recorded for this time of year, marking a 55 percent increase from the previous week.

Flu infections also rose in the week leading up to December 7, according to the latest data from the UK Health Security Agency (UKHSA).

Approximately 21 percent of those tested for flu received positive results, compared to 17 percent the week prior.

Experts believe that the increase in cases is attributed to a strain of flu known as ‘subclade K’ or H3N2.

This strain has mutated several times and differs from those typically encountered each flu season, resulting in lower immunity among the population.

Sun columnist and GP warned that this strain may be “more severe” than the usual flu and “more contagious.”

Flu and colds can share similar symptoms—such as coughing, sneezing, and a sore throat.

However, a significant indicator of a flu infection is “overwhelming exhaustion,” according to Dr. Suraj Kukadia, commonly known as Dr. Sooj.

“It’s the type of illness that will confine you to bed; it’s not something you can just push through while continuing your daily activities,” he explained in a recent video.

He elaborated on the differences between a cold and the flu, stating: “Flu is not merely a bad cold; it is caused by the influenza virus.

“It’s a viral infection that tends to strike hard and fast, especially in the winter when people are indoors with closed windows and doors, leading to increased coughing and sneezing, which aids the rapid spread of viruses.”

Another key indicator of flu is the rapid onset of symptoms.

Dr. Sooj noted: “Symptoms usually appear suddenly; one day you might feel fine, but the next day you could feel completely drained.

Symptoms of Subclade K

While different from strains circulating in previous years, H3N2 causes similar symptoms.

Dr. Zoe informed Sun Health that symptoms tend to appear “suddenly” and include:

  • Fever
  • General malaise
  • Body aches
  • Extreme fatigue
  • Coughing
  • Sneezing and a runny nose

Flu may also lead to a sore throat, loss of appetite, diarrhea, stomach pain, and nausea, as noted by the NHS.

Additionally, children may experience earaches and low energy, according to Dr. Zoe.

If you contract the flu, the best course of action is to remain at home, rest, and stay hydrated; you should begin to feel better after about a week.

However, be vigilant for six red flag symptoms in yourself or your child.

If you observe any of these, you should seek immediate medical assistance.

Call 999 or visit A&E if:

  1. You experience severe difficulty breathing—such as struggling to speak without pausing, gasping, or choking.
  2. You have severe chest pain in the center of your chest that doesn’t subside—it may feel like pressure, tightness, or squeezing.
  3. You have pain that radiates to your arms, back, neck, and jaw.
  4. You feel more drowsy than usual or have difficulty waking up.
  5. Your lips or skin appear very pale, blue, or gray—on brown or black skin, this is easier to observe on the palms of your hands.
  6. You begin coughing up blood.

You should schedule an urgent appointment or call NHS 111 if your baby or child has flu symptoms that concern you, or if you are pregnant, over 65, have a chronic medical condition, or a weakened immune system.

“People often describe symptoms like fever, muscle aches, headaches, chills, and an overwhelming sense of exhaustion.

“A dry cough is common, and even simple daily tasks may feel insurmountable.”

In contrast, colds typically have a slower

Eze Chidiebere Paul

Eze Chidiebere Paul

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