In your own words, explain why a virus such as the rhinovirus, which relies on close contact to spread, might evolve to favor less virulent forms

Viruses tend to become less virulent over time because those viruses capable of killing their hosts too fast don't have enough time to reproduce.

In conclusion, it has been proposed that viruses tend to become less virulent over time because those viruses capable of killing their hosts too fast don't have enough time to reproduce.

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Rhinoviruses are transmitted through the air or via contact. We might expect this sort of transmission to require a fairly healthy host (one who gets out and comes into contact with others) and, hence, to select against virulent strains. If we take precautions and try to stay away from people or avoid any contact with people, more hand-washing stations, increased attention to sanitization, and isolation of patients will help to reduce the transmission of the disease and, in the process, may favor the evolution of less virulent strains of the virus.

characterization of nanoparticles is a critical step in nanomaterial production as it provides information of dimension, morphology, surface charge, distribution and degree of surface functionalization.