Berlin | The dawn peak its nose at Berlin, and Lothar Kopp, 65, is already on the queue in front of a clinic in the borough of Reinickendorf in the German capital.
With a handful of others, he waits in the observance of safety distances of two metres and with a mask on the face to be tested for coronavirus is not like the others: without being sick, he wants to know if he caught the virus in the past and has therefore developed immunity.
“If I have already had the coronavirus, I can’t infect other people,” he says, in the hope that a serological test for antibody positive would allow him to visit his old mother without risk of contagion.
While the déconfinement starts in several countries, experts have raised the possibility of “passports immune” to allow those who have developed protection against the virus to return to work before the other.
Extensive studies are underway in Germany, where tens of thousands of these tests have been carried out. Moreover, the level of immunity of the population is also of interest to researchers and policy makers.
To find out how many people have already been infected, the State of New York is going to start tests in “aggressive”, announced governor Andrew Cuomo last week.
The regulator of the us, has even allowed manufacturers to sell their tests without formal permission.
The world health Organization and other doctors have cautioned, however, against the doubts regarding the accuracy and reliability of these tests, one unknown regarding the new coronavirus being, in particular, the duration of a possible immunity.
A positive serological test does not mean, therefore, not the end of the danger.
“Once we have the valid tests, we will not always not if a positive result really means a protection against disease, or how long this protection will last,” explains a spokesperson from the WHO to the AFP.
For Matthias Orth, a member of the executive board of the Federation of German biologists and physicians, (BDL), another big problem is the quality of the results: “false-negative”, for example, are possible.
“There are also coronaviruses fairly mundane and do not cause serious diseases” and that can bias the outcome,” he explains.
In any event, tests of serology rapid promising a result in 15 minutes with a few drops of blood collected at home on the finger are “an absurdity”, tranche M. Orth.
Better tests will be developed in the next few weeks, but “we’re not there yet”, he insisted.
70 000 tests
Moreover, if large studies such as the ones in Germany can be used to determine the proportion of the population having been infected, the limits of the tests that are currently available make it impossible to determine with certainty the proportion of people really immune.
So far, the studies, such as that launched last weekend in Munich about 3 000 households, chosen at random, are monitored with great interest.
Separately, Gangelt, in the region of Heinsberg, where was developed the first great centre of Covid-19 in Germany, researchers have determined that 14% of the population had been infected.
Beyond the studies, pharmaceutical companies in germany have also launched their range of serological tests.
Some 70 000 of these tests have already been completed in 54 German laboratories, according to the federation of laboratories aggregated ALM.
For dr. Ulrike Leimer-Lipke, who offers tests of immune status since mid-march to Reinickendorf, these tests have a meaning, because that is how we will know who is immune.”
According to her, “it is very important to know that for those who have parents or grand-parents that they love.”