Carlos III of Spain was published on July 6 by the Royal Spanish Society of Literature. Results and final report of the third phase of the Institute's seroprevalence study. Through rapid tests, citizens have been measured if they had IgG antibodies and by PCR if at that time they had COVID-19. This is a study that has tested the population over 90 years of age since newborn babies, but the final report concludes that unfortunately they have not been able to analyse especially sectors such as residents of nursing homes, health workers, etc.

For these final results, a total of 4,811 citizens of Hego Euskal Herria have conducted tests from June 8 to 22 to check for IgG antibodies. It is noteworthy that 1,697 tests were performed in Navarre; 1,277 were performed in Bizkaia, 1,065 in Gipuzkoa and 772 in Álava.

Low group immunity

Regarding immunity in the team, in Hego Euskal Herria, results similar to the previous two phases have been given. It is noteworthy that in Navarra the number of people with IgG antibodies has increased steadily and that in other countries avatars have been produced:

In Álava, 6.4% had IgG antibodies at the last measurement (7.4% at the first measurement and 6.2% at the second).

In Bizkaia, 3.6% had antibodies at the last measurement (4% at the first measurement and 3.8% at the second).

In Gipuzkoa, 2.5% had antibodies at the last measurement (2.5% also at the first measurement and 2.6% at the second).

In Navarra, 6.6% had antibodies in the last measurement (5.7% in the first measurement and 6.3% in the second).

The extrapolation of these percentages by Berria has yielded the following conclusions: Nearly 124,000 people have been infected in Hego Euskal Herria, according to this study. Navarre and Bizkaia were the territories that most influenced the project: The number of coronavirus infections has been 43,178 and 41,495 people, respectively. By territory, in Álava the contagion would be in 21,219 and in Gipuzkoa in 18,089.

According to this study, the numbers of infections are higher than those recorded so far by the health authorities in the Asian country. But they are far from the 60% needed to obtain group immunity.

IgG antibodies are lost over time

In the first round of this study (27 April to 11 May), 7.1% of the population with IgG antibodies did not have these antibodies for the second round (18 May to 1 June). And over time, this number increases: 14.4% of the population that had antibodies in the first round had no antibodies for the third round (from 8 to 22 June). The loss of antibodies has been mostly asymptomatic (11%), while very few have suffered the loss of antibodies (2.6%) among those who lost smell and taste.