Written By: Satata Karmakar | Published : January 20, 2026 2:59 PM IST
New Flu Variant Triggers High Alert In UK, Canada: High Fever Above 104°F to Severe Breathing Trouble - Key Signs of Influenza H3N2
Flu Alert In UK, Canada LIVE Updates: In the year 2019, the world witnessed the emergence of one of the deadliest and most lethal viruses - SARS-CoV-2 causing COVID-19. The virus was capable to wrecking havoc inside the body - from causing severe pneumonia symptoms to sudden stroke, the outbreak was so deadly that the WHO (World Health Organisation) declared it as a pandemic. After battling the virulent virus for over 5 years, just when the world was breathing a sigh of relief, another deadly virus strain is triggering fresh cases in the United Kingdom and Canada.
According to the latest reports, a new flu variant - called Subclade K, or 'super flu' is spreading rapidly across the UK and Canada, prompting authorities to enforce pandemic control safety measures in place.
Speaking to the media about the sudden surge in flu cases, a doctor said, "As an emergency room paediatrician in central Massachusetts, I'm seeing a tremendous amount of flu over the past few weeks. I'm hearing from colleagues in emergency rooms across the country that they are experiencing a similar explosion of flu cases". She further added, "In my emergency department, we're also seeing particularly high spiking fevers of 104 or 105 degrees, compared with more usual lower grade fevers. That in itself is not dangerous, but for young children it does result in more instances of febrile seizures and dehydration".
What is this new virus? How dangerous is it? Can it trigger another pandemic? Let's learn the answers to these questions and get a hold of whether a pandemic is on its way or it's just the season.
As per the CDC, in early January, New York state recorded the highest number of flu cases in a single week. Several other states, such as Colorado, are also experiencing record flu levels, and 44 out of 55 states and other jurisdictions are reporting high or very high flu activity.
The currently dominant virus strain in UK and Canada is the deadly flu strain called 'Subclade K'. Although, in the books of virology, the strain is called influenza virus H3N2, the media has given it a new name - 'super flu'.
As of date, the CDC estimates that flu has caused 15 million illnesses, 180,000 hospitalizations and 7,400 deaths this season. One small saving grace is that the flu this season hasn't come on concurrently with either a respiratory syncytial virus RSV or COVID-19 surge, as it often does.
As per authorities, flu infection can lead to symptoms such as:
Traditionally, the flu is most dangerous for people over 65 or those with underlying health conditions, with young children experiencing more mild symptoms. But this year's strain is hitting kids harder. They are arriving in the emergency room after having had a high fever of more than 104 degrees for 5 7 days, or with flu complications including febrile seizures, croup or severe dehydration.
As per the CDC, the dominant flu strain of this year is the 'subclade K' - a subtype of influenza H3N2. As per experts, the Subclade K was first detected in Australia in July 2025. As the current trends show - this variant is driving 91.5% of infections in the US and is also responsible for the peak in Canada.
Subclade K has proved itself to be a particularly infectious variant, based on how quickly the volume of flu cases has surged. Its dominance may be driven by mutations that make it different from previous strains. Some scientists speculate that H3 influenza viruses have circulated at relatively low levels the past few years, which may have led to lower levels of immunity in the general population.
Since flu cases are on the rise in UK and Canada, experts have asked everyone to follow proper safety measures to protect themselves from catchin the infection, here is what everyone must do right now:
Stay aware, listen to your body and the moment you start noticing any of the symptoms mentioned-above, make sure to consult a doctor or an expert at the earliest.
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