“During the 2023/2024 flu season, the number of deaths from all causes in Portugal was higher than expected for a period. This period occurred between weeks 51/2023 and 03/2024, which coincided with the flu epidemic”, says the report from the National Flu and Other Respiratory Virus Surveillance Program (PNVG).

This program allows for monitoring the circulation of viruses, describing flu activity and detecting and identifying influenza viruses, SARS-CoV-2, and Respiratory Syncytial Virus (RSV), among others circulating in the country, and includes the areas of clinical and laboratory.

“In relation to the identified period, potentially associated with the influenza epidemic, as they are temporally coincident, we estimate a total of 3,624 deaths in excess of what was expected, which corresponds to an excess of 34 deaths per 100 thousand inhabitants”, says the document.

INSA also states that excess mortality in this period reached its maximum value in the first week of 2024.

Data analysis also concluded that excess deaths were significantly observed in all regions of the continent, as well as in both sexes, being higher in females (35/100,000 inhabitants).

The report also indicates that an increase in the proportion of Covid-19 cases with age was observed, with the highest number of cases occurring in the 30 to 64 age group.

The genetic characterisation of the SARS-CoV-2 viruses, detected in the PNVG sentinel networks, showed the diversity and circulation of strains of the virus that causes the Covid-19 disease, says the document.

The SARS-CoV-2 viruses identified mostly belonged to the BA.2.86 lineage, of the Ómicron variant, and viruses belonging to the XBB recombinant lineage were also identified.