An experiment showed that, on average, cell phones have 18 times the number of infectious agents as a toilet handle. In the chain of infection, the cell phone would represent a

A reservoir is where infectious agents can survive and be carried. A cell phone’s contaminated surface can harbor infectious agents, so it acts as a reservoir in the chain of infection. It is not a host, which is a living organism, or a portal of exit or entry, which are routes into or out of a host.

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