The data released on Thursday from the first wave of the "Vaccinometer" report, which monitors vaccination against influenza in priority groups of the 2019/2020 influenza season, reveal that since 15 October, 573,195 Portuguese aged 65 or older have been vaccinated and 133,299 aged between 60 and 64.

The report highlights "the positive evolution, in terms of increased vaccination coverage", compared to the same period last year, of the group of people with chronic disease, which recorded the highest increase (5.4%), followed by the group of Portuguese aged between 60 and 64 years (3.8%) and health professionals (3.1%).

According to the data, 28.8% of individuals with chronic disease, 24% of health professionals in direct contact with patients and 20.6% of Portuguese aged between 60 and 64 have already been vaccinated.

They also say that 28.2% of people aged 65 and over have already been vaccinated, an increase of 0.7% compared to the same period last year.

The flu vaccination season started on 15 October in Portugal, which has two million vaccines available, 1.4 million to be given free of charge to risk groups in the NHS and about 600,000 for sale in pharmacies.

This year, for the first time, vaccines are tetravalent, protecting against four types of viruses, whereas so far they have protected against a maximum of three. The tetravalent vaccine increases the likelihood that the content of the vaccine will match the viruses that will circulate and the vaccine is expected to be more effective.