According to data from the study promoted by the Doctor Ricardo Jorge National Health Institute (INSA), the Algarve and Azores regions were those with the lowest total seroprevalence (80.2% and 84.0%, respectively).

"In relation to the characteristics of the population, the highest total seroprevalence is found in the population between 50 and 59 years of age (96.5%), in individuals with higher education (96.0%) and in individuals with two or more chronic diseases (90.8%)”, states the INSA in a statement.

The data shows that the age groups below 20 years were those with the lowest total seroprevalence (17.9% between 1-9 years and 76.8% between 10-19 years).

With regard to post-infection seroprevalence, the results indicate “overall lower values” than those obtained in the 2nd phase of the survey (7.5% versus 13.5%), which is probably related to the decay of specific antibodies of SARS-CoV-2 over time, said the INSA.