The super flu, fueled by the K variant, seems to have slowed down in Italy: there were around 820,000 new cases in the week of Christmas, from 22 to 28 December, a slowdown compared to the 980,000 infections of the previous week. While the total number of Italians who have ended up in bed since the start of surveillance rises to 6.7 million cases. The new RespiVirNet report just published by the Higher Institute of Health (ISS) may seem surprising, but for experts it is too early to claim victory. Also because the decrease in the total incidence of acute respiratory infections in Italy has a “physiological” reason, namely the fact that in this period there are fewer reports from family doctors as a result of the reduction in the number of visits during the holidays and also the closure of schools. However, the season promises to be intense and could surpass the record of over 14 million total cases recorded in Italy in the 2024-2024 season. That it is a super flu is also confirmed by the data arriving from abroad with many cases, many hospitalizations and several deaths: from the USA to England.
The numbers recorded by the ISS in the last week
The ISS report indicates that in the week from 22 to 28 December the incidence was 14.5 cases per 1,000 patients compared to 17.1 cases in the previous 7 days. The highest incidence is observed, as usual, in the 0-4 age group, with approximately 39 cases per 1,000 patients. Experts from the Institute’s Infectious Diseases department point out that the decline is “more evident in the data coming from the communities compared to the hospital flow. The incidence could therefore start to rise again, or in any case remain high in the coming weeks”. The intensity is very high in Sicily, high in Campania, medium in Piedmont, Emilia Romagna, Tuscany, Marche, Lazio, Abruzzo, Umbria and Puglia, while it is low in all the others. In the same week, both in the community and in the hospital flow, a high positivity rate for influenza was recorded in people with respiratory infections, especially in hospital settings (22.2% and 50.3% respectively). Surveillance of severe and complicated forms of influenza highlights an increase in the number of cases in week 51 (corresponding to the period 16-22 December) compared to the same week of the previous season. The most prevalent subtype among the severe forms is A(H3N2), i.e. the so-called K variant. It should be noted that the majority of cases of severe influenza with complications concern unvaccinated people. As regards the characterization of influenza viruses, in the community the percentage of A (H3N2) viruses is significantly higher than A (H1N1) pdm09 viruses. Even in the hospital flow, a higher percentage of A (H3N2) viruses is observed compared to that of A (H1N1) pdm09 viruses.
According to experts, infections will grow again
“This is a classic decline of any holiday season,” he warns Fabrizio Pregliascodirector of the School of Specialization in Hygiene and Preventive Medicine at the University of Milan. “We are awaiting the results of the next few weeks. It is possible that we are really on a plateau, at the top of the incidence value, but then the critical moment will be the return from holidays. I am thinking in particular – specifies the virologist – of the reopening of schools”. On the other hand, ISS experts also point this out: “The decline recorded this week could be attributable to the fewer reports made by family doctors in the week of Christmas, as also demonstrated by the fact that it is more evident in the data coming from the communities compared to the hospital flow”. For specialists in the Infectious Diseases department “the incidence could rise again, or in any case remain high in the coming weeks”. Even for the Roman epidemiologist Massimo Ciccozzi “there has been a small physiological slowdown in the flu, also due to the counts of the surveillance systems which slow down during the Christmas holidays. I expect an increase in infections as early as the next bulletin but the important thing is that the vaccinated have much milder symptoms compared to the non-immunised ones who however clog up the emergency rooms. I too, having been vaccinated, have caught the flu in recent days, but the maximum temperature I have had is 37.2 and this is thanks to the vaccine which keeps the symptoms of the disease low.”
The impact in England and the United States
In England too, flu cases are starting to stabilize, but hospitals remain full and health authorities are worried about the effects that the coming cold wave may have. In the country, among the first to experience the impact of super flu“hospital admissions still exceeded 3 thousand in the week before Christmas”, we read in the update released by the National Health Service. Although “slightly decreasing compared to the previous one”, hospitals “remain extremely crowded, with approximately 95% of adult beds occupied” and a total of “94,118 patients hospitalized every day”. In addition to influenza, the NHS specifies, “other winter viruses also continue to circulate, with an average of 707 patients hospitalized with Covid, while last week there were 285 patients hospitalized with norovirus per day”. If “flu cases have not increased further” it is also “thanks to the intensification of vaccination efforts by NHS staff”. At the moment “almost 18.5 million people have been vaccinated against the flu: half a million more than in the same week last year”. Meanwhile in the USA there is a surge in flu cases in the USA. The CDC, US Centers for Disease Control and Prevention, estimates that in the current season – up to December 20 – there have been at least 7.5 million cases, 81 thousand hospital admissions and 3,100 deaths from influenza; at least 8 children died. Among the hardest-hit states, the agency cites Colorado, Louisiana, New Jersey, New York and South Carolina. The flow of data from laboratory tests, outpatient visits, hospital admissions and mortality are all increasing. Hospitalizations have more than doubled in 7 days: over 19,000 people were hospitalized for flu during the last monitored week, compared to around 9,900 in the previous one. “Severity indicators remain low at the moment, but flu activity is expected to continue for several weeks,” the CDC predicts.
