"We predict that at the end of April or the first week of May, this first pilot survey will be launched in a population of about 1,700 people" who will be tested for serology to see if antibodies to covid-19 have been developed, said Fernando Almeida at the daily press conference to monitor the pandemic.

The head of the National Health Institute Dr. Ricardo Jorge (INSA) stressed that "it is debatable that it is now possible to carry out mass tests to detect antibodies" and that the countries that have already started them are at different stages of the pandemic in relation to Portugal.

"We know from the numbers we have and from the epidemic curve that we are, fortunately, controlling, that the number of immunized people, of people who developed these antibodies, is relatively small," he said.

“Later on, we will, of course, carry out a large survey of the population”, he assured, but this will only happen “when it is permissible for the population to have higher levels of immunity”.

For now, with the pilot tests, “the first proportions of immunization” will be measured, assessing whether people have had contact with the new coronavirus and have developed antibodies and whether they are “possibly immunized”.

Fernando Almeida stressed that it is still unclear whether “immunity is lasting or not”, indicating that scientists who are investigating the new coronavirus “will make a better statement on this issue”.

The experience at the Ricardo Jorge Institute, which will be done in partnership with the General Directorate of Health and with academics, will also allow us to better understand how the tests work, their effectiveness in detecting antibodies and “the logistics that will be necessary” to expand them to a wider population, he said.