Key Points

Acute Respiratory Infections

• In week 52 of 2025, indicators for acute respiratory infections (ARI) continued to rise in outpatient settings and hospitals, particularly among those aged 15 and older (stable among those under 15).

• This ARI activity was primarily driven by the use of healthcare services for influenza (in primary care and emergency departments) and for pneumonia (in hospitalizations).

Bronchiolitis (children under 1 year of age)

• 5th epidemic week.

• Syndromic indicators in community settings and hospitals, as well as virological indicators (with the exception of the positivity rate in hospital laboratories, which remained stable), continued to rise compared to week 51 of 2025, with a trend and magnitude similar to that of the 2024–2025 season.

Influenza and influenza-like illness

• 4th week of the epidemic and continuation of its upward phase in week 52-2025.

• In week 52-2025, syndromic and virological indicators for influenza continued to rise, with the exception of the incidence rate from the sentinel network, which decreased. The increase in syndromic indicators affects those aged 15–64 and is particularly pronounced among those over 65 (stable among those under 15).

COVID-19

• In week 52 of 2025, indicators are stable and at low levels.