What if the different symptoms where due to different types of coronavirus and because of cross reactivity they tested positive for COVID19 even though it was one of the other common coronaviruses.
They know this so they can pump up cases, attribute all to COVID 19 when its only the severe cases that are actually covid19.
An Outbreak of Human Coronavirus OC43 Infection and Serological Cross-reactivity with SARS Coronavirus
Conclusions
These findings underscore the virulence of human CoV-OC43 in elderly populations and confirm that cross-reactivity to antibody against nucleocapsid proteins from these viruses must be considered when interpreting serological tests for SARS-CoV.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2095096/ha