How does the author characterize the states of order and disorder in life and death terms? Why are viruses an exception to this rule?

From the text:

Once the cells in a biological machine stop working, it can never be started
again. It goes into a cascade of decay, falling toward disorder and
randomness. Except in the case of viruses. They can turn off and go dead.
Then, if they come in contact with a living system, they switch on and
multiply. The only thing that "lived" inside this monkey was the unknown
agent, and it was dead, for the time being. It was not multiplying or doing
anything, since the monkey's cells were dead. But if the agent touched living
cells, Nancy's cells, it would come alive and begin to amplify itself. In
theory, it could amplify itself around the world in the human species.