Or just do some good old inferring: if there was a lab accident with 3 workers showing symptoms of a common cold seeking medical assistance (and them spreading

Or just do some good old inferring: if there was a lab accident with 3 workers showing symptoms of a common cold seeking medical assistance (and them spreading infections along the metro line of their commute to the hospital), this must have been the superspreader event of the century. How comes, the general rate of cold symptoms within lab workers conforms to what is statistically expected? Why is there no spreading in their social vicinity? How and why were they apparently infectious only on their individual rides to the hospital? You really have to come up with a theory that may explain this very selective and peculiar pattern of spreading. Otherwise you may turn your interest towards an entirely different theory of origin.