A filter medium is provided with a first layer as a support layer and a second layer as a filtration layer arranged downstream of the first layer. The first layer and the second layer both are provided with at least one active agent that is at least antibacterial. The active agent can be applied as a coating or as an impregnation. Examples of active agents are pyrithione, a metal salt of pyrithione, a pyrithione derivative, a metal salt of a pyrithione derivative, and a quaternary ammonium salt. A filter element is provided with such a filter medium in the form of a filter media pack. The filter medium and filter element can be used in a water injection system for internal combustion engines.
