Data published in the Influenza Epidemiological Surveillance Bulletin reveal that in the week of December 16th to 22nd, 35 cases of severe acute respiratory infection (SARI) were admitted to ULS São José, in Lisbon.

According to INSA, the SARI incidence rate was 10.2 per 100 thousand inhabitants, showing an increasing trend compared to previous weeks.

The Portuguese Network of Laboratories for the Diagnosis of Influenza and Other Respiratory Viruses detected 377 positive cases for the influenza virus in that week, of which 333 were type B and 44 were type A. In 13 of the cases, subtype A(H1N1) was identified.

According to the bulletin, in the week of December 16th to 22nd “a greater number of flu cases were detected, compared to previous weeks”, with one case of flu being reported among the nine Intensive Care Units that sent information, and it was identified as Influenza B virus.

20 cases of acute respiratory infection/flu syndrome were analysed and seven positive cases for the influenza virus and two positive cases for the respiratory syncytial virus were detected. No positive cases have been detected for the SARS-CoV-2 virus.

According to INSA, other respiratory agents were also identified in 342 cases, with respiratory syncytial virus being the most frequently detected.

Within the scope of the National Flu Surveillance Program, in the 2024/2025 season, as of September 30, 354 cases of acute respiratory infection/flu syndrome were analysed and 48 (13.6%) cases of influenza were detected, of which 42 (87.5%) of type B and 6 (12.5%) of type A.

11 (3.1%) positive cases for SARS-CoV-2 and 7 (2%) positive cases for respiratory syncytial virus were identified.