4 ms·
> The more deadlier a virus, the rest likely it is to spread. Not really. The two primary factors controlling how fast a disease spreads is the infectiousness
by TomSwirly 4y ago
> The more deadlier a virus, the rest likely it is to spread.
Not really. The two primary factors controlling how fast a disease spreads is the infectiousness (R0 or other similar measures), and how long victims are infectious before they display symptoms.
The deadliness, the victim living or dying, happens significantly after they've finished their role as spreader of disease and thus does not significantly affect the spread.
Ebola fails to spread, not because it's deadly, but because the symptoms are almost immediate and dramatic.
(I took graduate level course in the mathematics of epidemiology and got an A, which makes me no expert at all, but this is fairly fundamental.)
- inglor_cz 4y agoI gave the OP another example of a deadly and yet widespread virus, HIV. He is not completely off the ball, though. Our immune systems are rather good, so (with significant exceptions like HIV) if some virus doesn't kill us quickly, we tend to clear it out of the organism or at least get it under control, so it won't kill us at all. Viruses that are very deadly but take a long time to kill you (thus enhancing the risk of transmission), like HIV, aren't very typical.