Wikipedia defines a viral phenomenon as:
... objects or patterns that are able to replicate themselves or convert other objects into copies of themselves when these objects are exposed to them. They get their name from the way that viruses propagate.
We all might be familiar with viral videos, etc. For example:
I wonder if this is how viruses really behave. If we focus for instance in this key dimension - that of the spread of viral phenomena, we see substantial heterogeneity. For instance, the global number of individuals infected with HIV can be seen below:
Doesn't look so viral. The recent outbreak of Ebola in Africa seemed to be quite viral though, but not that of MERS:
The behaviour of SARS was also quite "viral" but reached a plateau very quick:
The Marburg virus, in contrast, does not look viral at all:
Meanwhile, other viruses seem to be seasonal, e.g. hendra virus, or the common cold.
Again, all these seems to me to indicate substantial heterogeneity in the propagation of viruses. Sure, the endogenous response of humans to viruses is an important element to take into account, but viral phenomena are not autonomous either; they respond to human agency.
Could we then conclude that the biological "virality" of viral phenomena is more of a misconception than a true description of viruses propagation? Perhaps another term could be more appropriate?