In the forty-sixth week of 2025, the incidence of influenza-like syndromes (ILI) in Italy stands at 7.91 cases per thousand assisted, a value placed in the low intensity range. According to estimates, there are around 14 thousand new cases of flu in Italy. Monitoring is carried out by the Istituto Superiore di Sanità through the Influnet network, which every week publishes an update on the trend of influenza and respiratory viruses. The data allows us to observe the evolution of the epidemic season in relation to previous years. The WHO for Europe is also analyzing the evolution of the flu across the continent by evaluating the trends and identifying the period most feared by everyone, the one relating to the peak of flu.
When is the flu peak expected?
The value of 7.91 cases per thousand assisted represents the highest peak recorded so far in the 2025-2026 season. In the previous weeks, the incidence had remained below this threshold, signaling a progressive increase typical of the beginning of the flu season. In comparison with the historical series, the figure remains far from the highest peak of recent years: in the fifty-second week of the 2023-2024 season the incidence had reached 18.45 cases per thousand assisted.
The current trend therefore appears more limited, although showing signs of growth to be monitored in the coming weeks. According to theWorld Health Organization for Europe “The flu season started about 4 weeks earlier than usual and based on previous trends, this season is expected to peak at about 50% positivity in late December and early January.”
Regional differences: where the incidence is highest
The geographical framework ofHigher Institute of Health shows a variable intensity across the territory. The region with the highest incidence is Piedmont, which reaches 8.83 cases per thousand assisted. This is the highest value at a national level in the week analyzed. Several regions fall into the low intensity range: Friuli-Venezia Giulia, Emilia-Romagna, Sicily, Abruzzo, Lombardy, Puglia, Lazio, Sardinia, Tuscany and Marche. At the basal level are Umbria, Molise, Campania, the autonomous province of Trento, Liguria, Basilicata, Veneto, the autonomous province of Bolzano and Valle d’Aosta.
As regards weekly variations, Puglia recorded the most limited decline, with a drop of 0.15 points (from 8.3 to 8.15). The most significant increase concerns the Autonomous Province of Bolzano, which goes from 2.87 to 6.59, with a growth of 3.72 points.
The age groups most affected
As happens every year, the data confirms the greatest impact among the smallest. Pediatric children record the highest incidence, equal to 25.68 cases per thousand assisted, a value significantly higher than that observed in the other categories.
The children and pre-adolescents range follows, with 7.99, while adolescents and adults stand at 7.59. The lowest incidence concerns the elderly, equal to 4.76 cases per thousand assisted. These differences obviously reflect the greater exposure of children and adolescents, especially considering school and social contexts. In these situations the transmission of respiratory infections occurs more easily.
