An outbreak of Halomonas phocaeensis sp. nov. bacteraemia in a neonatal intensive care unit.

Unidentified Gram-negative aerobic rods were recovered from the blood cultures of six neonates in a neonatal intensive care facility in Tunis, Tunisia. 16S rRNA gene sequencing showed that these were members of the Halomonas genus, with <97% sequence similarity to their closest relative. The observation of unique phenotypic characteristics of these organisms supported a novel species and the name Halomonas phocaeensis sp. nov. was proposed. A case-control study and conditional logistic regression analysis suggested that the administration of fresh frozen plasma was the only independent risk factor for developing H. phocaeensis bacteraemia. Observational studies indicated that fresh frozen plasma was warmed up using a water-bath. This first description of a nosocomial outbreak of H. phocaeensis bacteraemia illustrates the infection risks associated with poorly controlled water hygiene in healthcare settings.