All the trials that have been done for coronavirus vaccines before 2019 have failed miserably and have caused very severe reactions in animals until death. In less than 1 year scientists have succeeded in making a miraculous vaccine? Which they did not manage to do during the last 20 years?
Here is the study with ferrets from 2012:
“These SARS-CoV vaccines all induced antibody and protection against infection with SARS-CoV. However, challenge of mice given any of the vaccines led to occurrence of Th2-type immunopathology suggesting hypersensitivity to SARS-CoV components was induced. Caution in proceeding to application of a SARS-CoV vaccine in humans is indicated.”
Here are the same results in cats:
And the same results in mice:
journals.plos.org ( https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0035421 )