In the forty-eighth week of 2025 the incidence of acute respiratory infections in Italy it continues to grow. The bulletin RespiVirNetpublished by the Istituto Superiore di Sanità, records a increment compared to the previous week, confirming the expansionary phase typical of the winter period. The monitoring is based on the new operational protocol, which broadens the definition of cases and allows a more complete reading of the viral circulation in the area.
Incidence and national trend
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The overall incidence rises to 9.34 cases per thousand assisteda growing value compared to the 8.96 cases of the previous week. This is one of the highest levels of the 2025-2026 season and reflects the intensification of the circulation of respiratory viruses, favored by the arrival of cold weather and the increase in opportunities for contact indoors.
The increase is determined by a co-circulation of different pathogens. Influenza viruses show a growing role, joined by Rhinovirus, Adenovirus and other seasonal respiratory viruses. As indicated by the ISS, this plurality of infections contributes to a heterogeneous epidemiological picture, without a single predominant culprit.
The new surveillance system also takes into account a wider range of diagnoses, which is why the data is more sensitive to weekly variations. However, the upward trend remains evident, consistent with the trend observed in recent years.
The age groups most affected
The bulletin confirms that the little ones they are still the most affected age group. The incidence among children aged 0 to 4 years reaches 30.12 cases per thousand assisted, a value that remains significantly higher than the rest of the population. Distribution by age (per 1,000 assisted):
- 0-4 years: 30.12
- 5-14 years: 10.28
- 15-24 years: 8.92
- 25-44 years: 10,11
- 45-64 years: 7.54
- 65+ years: 5.32
The central segments of the adult population show a slight but constant increase, while the over 65s record a lower incidence than children but still growing, signaling the importance of vaccination against influenza and Covid-19 for the most fragile categories.
The situation in the regions
The territorial differences continue to be marked. Also in week 48, Sardinia is the region with the highest incidence, equal to 14.55 cases per thousand assisted, followed by Lombardy (9.78‰) and Sicily (9.66‰). The central regions record more moderate but still increasing values.
| Region / Autonomous Province | Incidence (per 1,000 patients) |
|---|---|
| Abruzzo | 10,82 |
| Basilicata | 6,61 |
| Campania | 10,21 |
| Emilia-Romagna | 9,05 |
| Friuli Venezia Giulia | 8,47 |
| Lazio | 8,95 |
| Liguria | 7,12 |
| Lombardy | 9,78 |
| Marche | 9,15 |
| Molise | 4,59 |
| Piedmont | 9,87 |
| Autonomous Province of Bolzano | 6,14 |
| Autonomous Province of Trento | 4,98 |
| Puglia | 9,41 |
| Sardinia | 14,55 |
| Sicily | 9,66 |
| Tuscany | 7,92 |
| Umbria | 5,03 |
| Aosta Valley | 6,26 |
| Veneto | 8,71 |
| Calabria | data not available |
The virological landscape
In the hospital flow we observe a increase in positivity rates for influenza viruses, while Rhinoviruses still remain among the most detected. Prevalence varies from week to week, but influenza and Rhinovirus continue to be major players both in the community and in hospitals.
For SARS-CoV-2, the highest rates remain concentrated in the over 65 age group, consistently with the historical data of the last winter seasons and with the recommendation of the health authorities to vaccinate against Covid-19 and influenza.
When the peak comes
According to international epidemiological assessments, the peak of respiratory infections could be between the end of December and the beginning of January. The current trend is similar to that observed in some recent seasons, characterized by an advance in cases and sustained circulation of the A/H3N2 influenza strain. The ISS bulletin also reminds us that surveillance on emerging variants remains active, which could influence the evolution of the epidemic.
