British scientists have now found laboratory evidence of the most likely cause: a cross-immunity of the persistently “pumpers healthy” to the Covid-19 pathogen through a previously experienced infection with “normal” coronaviruses, which have long been causing coughs, runny nose and hoarseness . The research results might also have implications for future vaccine development. Apparently T cells, which have formed in response to an infection with human corona cold viruses (huCoVs), seem to play an important role in this cross-immunity. The hypothesis is not new, but so far there has been a lack of convincing evidence that has now been provided by scientists.
