Candida colonization in the nursery.

There is a wide range of variability in the reported frequencies of fungal colonization in NICUs due to several factors. Inconsistencies in surveillance culture policies make it difficult to compare the incidence rates of different settings and institutions: as a result, NICUs performing weekly (or semiweekly) cultures for each patient will claim higher incidence rates of colonization than those that do not have such a policy. Moreover, it is known that in preterm neonates colonization originates from both acquired (horizontal transmission) and endogenous source, and also from colonized mothers (vertical transmission). These two different modalities show some overlap over time, making it difficult to ascertain both the origin and frequency of colonization in neonatal settings.