Abstract
We evaluated the discriminative power and usefulness of the DNA array technology as compared to DNA macrorestriction pattern analysis for monitoring epidemiologically related clusters of
Listeria monocytogenes strains that differ slightly in DNA macrorestriction patterns. We show that this approach allows clarifying the genetic basis of the pattern variations. In the reported outbreak, the differences were due to phage excision, showing the power of this technique in epidemiological studies.