A FLAVOBACTERIUM-MENINGOSEPTICUM OUTBREAK AMONG INTENSIVE-CARE PATIENTS

A Flavobacterium meningosepticum outbreak, involving 12 infected and 4 7 colonized intensive care patients during the months of February thro ugh July 1990, was investigated. F. meningosepticum was isolated from tap water and ice, but these environmental strains eventually proved t o be distinct from those colonizing patients. A review of newly coloni zed patients' charts revealed that a common factor among the patients was daily changes of ventilator tubing pasteurized in the hospital's c entral sterile department. More than 90% of patients in the outbreak h ad been on ventilators that used the pasteurized tubing. An investigat ion of the pasteurization process found that two pasteurizer tanks had been operating at suboptimal temperatures (< 62-degrees-C). Cultures of water from the tanks and droplets of water found in the pasteurized tubing grew species of Acinetobacter, Moraxella, and Pseudomonas but did not grow F. meningosepticum. After deficiencies in the pasteurizat ion process were corrected, the outbreak terminated. Despite the failu re to culture F. meningosepticum, an analysis of gram-negative bacilla ry isolates showed that the deficiency in the pasteurization process w as a major contributor to colonization of ventilated patients by bacte ria ubiquitous in tap water.