In civilian life, natural selection favours a mild strain.

Generally, an infected plant does not produce fruit, although mild strains exist which allow some production.

Only amphibians with a mild strain of the parasite would return to the pond to mate.

However, inoculation of the mild strain also caused pathogenesis on the papaya plants.

The 'King of the World' was placing only a mild strain on hyperbole by proclaiming his global reach.

If so, can scientists determine what components of the virus account for the difference between mild and lethal strains?

I think it's probably more of a mild strain.

Or maybe some restraint, anyway, for there is throughout a mild strain of Captain Underpants-style humor.

Pakistan announced Monday that chickens there had been infected with a mild strain of bird flu.

Somehow, a tear became a mild strain.