Journalist Garan BEÑAT Zaldua explains that if the laboratories that are prepared to do so in the CAV were set in motion, Osakidetza workers could have the PCR tests in just over three days. Why is this opportunity not being used?

Speaking to Radio Vitoria, Arantxa Mendizabal, head of the laboratory and clinical analysis of the Integrated Health Organization of Álava, said last Thursday that the laboratories are not working to the fullest, that they can do more tests than they are doing now. That is, despite the fact that health care has lived for weeks in which professionals have not been tested, laboratories have not been making use of their full capacity. Something does not match the situation, as Zaldua stressed in Gara.

In addition, the type of test to be performed is questioned. Most of the tests performed so far are PCR type, the most reliable for the time being, since they detect infection at an early stage. They don't detect any past contagion. A PCR test indicates whether the virus is in a person's body, not if it's been before. Antibody tests, on the other hand, are less reliable and often require a PCR to confirm the diagnosis. That is, it detects the antibodies that the body has created, and from there it deduces that someone has already passed the evil.

Do you prefer immunity tests to PCR?

Speaking of these two tests, Mendizabal noted that PCR is not a "response to everything", and that, for example, they are not the best starting point for population analysis, as "at this time they will only show us infected people". According to Mendizabal, the priority of Osakidetza is to perform a type of test that determines collective immunity, so tests that detect antibodies will be prioritized.

But to detect cases and control the pandemic, PCR has so far been the most reliable tool. This is demonstrated by the case of South Korea: this Friday Seoul has published an extensive report on the control of COVID-19 in the country. The abbreviations PCR appear several times, but antibody tests are not mentioned.

Why, then, gamble on tests that detect antibodies instead of that path? These tests have had to be ordered abroad and the Basque Government has not disseminated much information on this point. In addition, Mendizabal, in an interview with Radio Vitoria, noted that many of these tests do not serve, as their ability to detect true positives is less than 40%. But then he explained that “Donostia’s peers have tried Osakidetza’s requests and are “perfect”.

What the WHO says about immunity tests

In the World Health Organization, they are not so sure of this statement. In statements collected by the BBC, María van Kerkhove, head of the emerging disease unit, said that "many countries are suggesting, along the lines that Osakidetza is assuming, the use of rapid serological tests for diagnosis to achieve a level of immunity of the population". But for the WHO member, “at this time we have no evidence that the use of a serological test can demonstrate that an individual has immunity or is protected from the risk of re-infection.”

According to Van Kerkhove, “antibody tests can measure the degree of seroprevalence, but that doesn’t mean someone who has antibodies is immunized.” In this regard, in Gara they recalled that last week South Korea reported 91 cases in which patients who were discharged, supposedly immunized, have returned positive. It is being studied whether they have been reinfected, but, in any case, remember that we still know very little about this coronavirus that has brought the world to dance.