In the week of December 20th to 26th, “it was estimated an incidence rate of flu syndrome of 19.9 per 100,000 inhabitants”, refers the bulletin of epidemiological surveillance of influenza and other respiratory viruses of the INSA.
In the case of covid-19, the incidence of infections was, on Wednesday, at 923.4 cases per 100,000 inhabitants nationwide.
The values of clinical influenza surveillance, which must be interpreted taking into account that the population under observation was smaller than in homologous periods of previous years, were calculated through the medical-sentinel network, an information system made up of general practitioners and familiar from the mainland and the autonomous regions.
As for laboratory surveillance, which allows the identification of various respiratory viruses, the INSA report indicates that the Portuguese network of hospital laboratories detected, in the same week, 22 positive cases for the flu virus, all type A.
“The virus for which the subtype has been determined is A(H1)pdm09. Other respiratory viruses were detected, mostly respiratory syncytial virus”, indicated the INSA.
Regarding the severity indicator, one case of flu (influenza A) was reported by the 17 intensive care units that sent information, with no flu situations having been reported by the wards.
Vaccination against flu started in Portugal at the end of September, earlier than usual due to the covid-19 pandemic, with more than 2.4 million people already being immunized, according to data from the Directorate-General for Health.
In Portugal, the surveillance system for influenza and other respiratory infections comprises the network of sentinel doctors, the emergency services, the service areas dedicated to respiratory patients, the Portuguese network of laboratories for the diagnosis of the flu virus and the intensive care units.
This annual program starts in early October and ends in May of the following year, and integrates clinical and laboratory components.