It is unlikely that all scientists in Paris, Milan, Turin, Bologna, Barcelona and Florianópolis were just wrong, independently of one another. If there were any errors, they must be in the PCR tests and something was measured that was not Covid-19. Then, however, the entire tests on the saliva samples must also be faulty and display something that was not a corona infection. Either the scientists are right and we have been living with the virus for a long time, it has only just been discovered, or the tests are useless and we can throw all the statistics into the garbage can. The political decisions then lack any data base.