HOUSTON, Texas – A fast-moving flu strain that has already caused unusually heavy outbreaks in several countries is raising concerns as the United States heads into peak flu season.
The virus, a form of H3N2, has been spreading earlier and more aggressively than expected in places such as Canada, the United Kingdom, and Japan, a pattern that public health officials say could signal a tougher season ahead for Americans.
In recent months, doctors abroad have reported larger-than-normal clusters of flu cases, weeks before their typical peak.
Some hospitals have seen patient numbers multiply compared to last year, a sign that the virus is spreading.
The timing matters: when outbreaks begin earlier overseas, the U.S. often sees a similar shift.
Scientists are particularly worried about this year’s H3N2 because the strain has drifted genetically from the version included in the current flu vaccine.
That mutation doesn’t make the shot useless, but it may make it less effective at preventing infections.
Even so, health experts stress that vaccination remains the strongest protection against severe illness, hospitalisation and death, especially for older adults and people with underlying conditions, who tend to fare worse during H3N2-dominant seasons.
Another challenge is limited visibility into what’s happening in real time. U.S. flu surveillance has had data gaps this fall, making it more difficult to track which strains are circulating and how quickly.
That uncertainty leaves health officials preparing for several scenarios at once, including the possibility of a faster-moving season with higher hospitalisation rates.
If flu activity here follows trends overseas, Americans could see cases rise sooner than usual, potentially overlapping with other respiratory viruses and adding pressure to already-busy hospitals.
Doctors say now is the time for people to get vaccinated, practice good hygiene and pay attention to symptoms, especially if they’re in a higher-risk group.
While there’s no way to predict exactly how the season will unfold, the early signals from abroad have put the U.S. on alert.
Health officials say awareness, not panic, is key, and that taking preventive steps now could make a significant difference as the season intensifies.