This is a common theory in analytics of the epidemiology of various diseases. The reported data tends under report the real number of cases due to a lack of testing. You combine this with the fact that the majority of coronavirus victims will be asymptomatic for a certain period while the disease is transmissible, you're looking at large swaths of the population to contract coronavirus. Still though, suggesting that half have the disease already is a bit of a stretch this early. We're not going to know the true numbers of coronavirus until months after this is over once widespread testing is enacted in countries expanding South Korea.


China has widespread testing but I wouldn't trust a single number they put out.