Just copying this here ,from WHO today
First, COVID-19 does not transmit as efficiently as influenza, from the data we have so far.
With influenza, people who are infected but not yet sick are major drivers of transmission, which does not appear to be the case for COVID-19.
Evidence from China is that only 1% of reported cases do not have symptoms, and most of those cases develop symptoms within 2 days
Perhaps someone with a more analytical mind can look at this .To me it seems to say .that the data ie in China's reported cases only 1% were without symptoms .Therefore it's not like flu where a higher percentage of people pass on the illness before they are aware that they are ill .
But is that all they are basing the " COVID-19 does not transmit as efficiently as influenza" on ? Are there are other considerations /data not mentioned ?
Could there have been a large number of unreported cases in China of which a high percentage had Covid 19 but didn't realise it ?