Healthcare systems in Europe, the US and Asia are again on alert after an unusual flu outbreak, specifically a K variant of the H3N2 virus, foreign media write.
According to reports, the start of winter in the northern hemisphere is marked by an increase in flu cases 3 to 6 weeks earlier than expected.
Countries such as Germany, France, Italy, the United Kingdom, Spain, the United States, Canada and Japan have seen an unprecedented demand for healthcare, especially among young children, the elderly and people with chronic illnesses.
In Spain, data from the Carlos III Health Institute (ISCIII) shows a flu rate of 112.2 cases per 100,000 inhabitants, almost ten times higher than the same period last year. Germany and the United Kingdom are also reporting figures that far exceed previous data and have already reinforced their hospital infrastructure. In the United States, the Centers for Disease Control and Prevention (CDC) confirm that the K variant is becoming dominant and warn that the epidemic could extend into the spring.
The flu arrived accompanied by the circulation of respiratory syncytial virus (RSV) and SARS-CoV-2, which worsens the condition and complicates diagnosis.
The K variant of H3N2 includes several mutations, allowing the organism to partially evade both natural immunity and that generated by current vaccines. Andrew Pekosz of Johns Hopkins University argues that these genetic changes increase the transmissibility of the virus, especially in closed, poorly ventilated environments during the winter.
Symptoms usually include high fever, muscle aches, dry cough, and fatigue.
Doctors warn that this condition can be confused with COVID-19 and other respiratory viruses, so they recommend performing combined tests for an accurate diagnosis.