Before revision:  Combining both pathways, the basic reproduction number \mathcal{R Viral load, minimum infectious dose, sensitivity of the virus half-life to the phase of its vector , extent of dilution of the respiratory jet/puff by the entraining air are the important factors that determine specific physical modes of transmission and the pandemic evolution .
After revision:  Combining both pathways, the basic reproduction number \mathcal{R Viral load, minimum infectious dose, sensitivity of the virus half-life to the phase of its vector , extent of dilution of the respiratory jet/puff by the entraining air are shown to mechanistically determine specific physical modes of transmission and the pandemic evolution .