The flu is back with a vengeance, and Portugal is officially in the midst of an epidemic. But here's where it gets concerning: this year's outbreak is showing a worrying upward trend, with more people ending up in the hospital.
Just like the UK and other countries, Portugal is urging its citizens to take precautions to prevent the spread. This means covering coughs, washing hands frequently, and for those most at risk, getting vaccinated. Dr. Ricardo Jorge, from the National Health Institute, confirmed that the country has entered an 'epidemic phase of influenza' with a rising number of confirmed cases, including some requiring intensive care.
And this is the part most people miss: The data, as explained by Raquel Guiomar, head of the National Reference Laboratory for Influenza, shows a significant increase in flu activity during week 48 of 2025, starting November 24th. This isn't just a minor uptick; it's a clear sign of an epidemic.
The Sentinel Physicians Network has reported a surge in lab-confirmed flu cases over the past few weeks. The INSA Epidemiological Surveillance Bulletin highlights a concerning rise in severe acute respiratory infections, reaching 10.5 cases per 100,000 people during the week of November 24-30. While this might seem like a small number, it's a notable increase compared to previous weeks.
Here's the controversial bit: The elderly and young children are bearing the brunt of this outbreak. The age groups from 0-4 and 65+ have seen the most significant rise in cases, with the elderly being particularly vulnerable. This week alone, 82 severe cases were admitted to Local Health Units, with 10 requiring intensive care. Interestingly, only three of these patients had received the seasonal flu vaccination, despite all of them having underlying health conditions that made vaccination crucial.
Raquel Guiomar points out that the severity of the flu often depends on the circulating virus strain and the individual health of each patient. Currently, two types of influenza viruses are circulating: A and B. Influenza A, particularly the AH1N1 subtype, is dominant, though the AH3N2 subtype is also present.
But here's the twist: The AH3N2 virus has evolved. A new subgroup, designated K, has emerged and already accounts for about 45% of AH3N2 viruses in Portugal. This subgroup has mutations that may enhance its transmission and infection rates, making it different from the viruses covered by the 2025-2026 vaccine. This raises questions about the vaccine's effectiveness against this new strain.
The epidemic arrived earlier than usual in Portugal, mirroring the pattern seen in 2023-24. However, we haven't reached the peak yet, and the trend is still upward. While SARS-CoV-2 circulation is low, and respiratory syncytial virus (RSV) activity remains minimal, the flu is the primary concern.
Health Minister Ana Paula Martins warned of a challenging winter last month, but the reality is that Portugal's health service faces staffing and management issues year-round. The flu only exacerbates these existing problems. The real question is: Are we prepared for this evolving virus, especially when the vaccine might not fully cover the circulating strains?
What do you think? Is Portugal doing enough to combat this flu epidemic? Share your thoughts in the comments below!
