Is flu going around in Spain?

Flu in Spain typically begins rising in December, peaks between January and February, and eases through March. The Instituto de Salud Carlos III (ISCIII) runs the SiVIRA integrated surveillance system for respiratory viruses and publishes weekly bulletins. Timing and intensity vary season to season depending on the dominant influenza subtypes and residual immunity in the population.

Through SiVIRA, ISCIII publishes weekly reports covering primary-care incidence, hospital admissions for severe acute respiratory infection, ICU admissions, and virological positivity from sentinel networks. Activity is described in qualitative bands against historical thresholds. Spain also contributes to the ECDC European Respiratory Virus Surveillance Summary (ERVISS), so the Spanish curve can be compared directly with other EU countries.

SiVIRA integrates primary-care and hospital streams. Sentinel GPs and paediatricians record ILI consultations and submit swabs for virological testing at reference laboratories. Hospital surveillance captures severe acute respiratory infection admissions and ICU cases, coordinated between ISCIII and the autonomous communities. Results are published weekly and feed into both national bulletins and the ECDC ERVISS platform.

Spain offers free seasonal flu vaccination through the Sistema Nacional de Salud to groups at higher risk, including adults aged 60 or 65 and over depending on the autonomous community, pregnant women, people with certain long-term conditions, children in defined age ranges, healthcare workers, and carers. ISCIII and the Ministerio de Sanidad publish coverage data alongside weekly surveillance in SiVIRA.

Each season is shaped by the dominant influenza subtype and accumulated immunity. SiVIRA reports plot current indicators against recent seasons, and ECDC ERVISS places Spain in its European context. Some seasons in Spain peak sharply in January, others are drawn out into March. The weekly bulletins make clear whether current activity sits above or below the recent historical average.