В последние несколько дней несколько школ в Великобритании были вынуждены временно закрыть из-за аномального роста сезонного гриппа, вызванного мутацией подварианта H3N2, известного как «субклад K». Самый значительный вспышка произошла в Каэрфилли (Уэльс), где более 250 учеников и сотрудников одновременно заболели. В связи с этим образовательные власти opted for a thorough disinfection and a temporary suspension of classes to reduce the number of infections. Symptoms among affected students (vomiting, fever, diarrhea, headache, and fatigue), similar to those of COVID-19, forced several centers to suspend their activities. In addition, chills often appear very abruptly with this strain. According to Noticias Argentinas, the decision comes at a time of increasing pressure on the National Health Service (NHS), which recorded 1,717 hospitalizations for flu at the end of November — the highest figure for this period in recent years. Meanwhile, the UK Health Security Agency (UKHSA) has warned that the mutation has increased the virus's transmissibility, although the vaccine's efficacy remains stable compared to previous seasons. As this new H3N2 flu subclade K variant is highly transmissible, experts predict a sharp increase in cases and have warned of the risk of co-infections (flu and avian flu) and advised urgent vaccination. The high transmissibility of this variant is attributed to significant genetic changes within the subclade K, according to experts.