According to Instituto Nacional de Saúde Doutor Ricardo Jorge (INSA) data on the epidemic curve of infection by SARS-CoV-2 released on 26 March, for the five-day period between 17 and 21 March, saw the Algarve register an Rt of 1.19, the Alentejo of 1.02, the Azores 1.04 and Madeira 1.05.

The remaining regions of the country have a virus transmissibility index below 1: North 0.95, Centro 0.85 and Lisbon and Vale do Tejo 0.89.

In the previous report, released on 19 March, all regions of mainland Portugal had a virus Rt of less than 1, with the exception of the Azores, which registered 1.20.

On Tuesday, INSA investigator Baltazar Nunes, who is part of the group of experts that supports the Government in decision-making in the context of the covid-19 pandemic, had warned that Rt 1 is the limit set in the analysis of the evolution of the easing of lockdown plan.

"It is natural for the rate of decrease to slow down, although it also has its risks", stressed Baltazar Nunes at the time, while noting that the cumulative incidence of cases per 100,000 inhabitants within 14 days is below 120.

According to INSA data released today, the average value of Rt - the number of secondary cases of covid-19 resulting from an infected person - is 0.93 at the national level, when in the previous report it was estimated at 0.86.

All regions have an incidence rate of less than 120 cases, ranging from 55 to 82, with the exception of Madeira, which has a value of 305.2.

These indicators - the rate of transmissibility of the virus and the incidence rate of new cases of covid-19 - are the two criteria defined by the Government for the continuous assessment that is being made of the process of easing lockdown that started on 15 March.