Endemicity and inter-city spread of Burkholderia cepacia genomovar III in cystic fibrosis

Objectives: We sought to determine whether the same Burkholderia cepacia co mplex strain has persisted as the dominant clonal lineage among patients in a large cystic fibrosis (CF) treatment center during the past 2 decades. Study design: The inter-city spread of B cepacia through transfer of a colo nized patient and the impact of infection control measures in containing in terpatient transmission were investigated. We analyzed all available B cepa cia complex isolates recovered from 1981 to 1987 and from 1996 to 2000 at o ne large CF treatment center (Center A) and from 1997 to 2000 at another ce nter (Center B). Incidence of B cepacia complex infection and infection con trol measures in both centers were assessed. Results: Seventeen (81%) of 21 Center A patients from whom B cepacia. compl ex bacteria were recovered between 1981 and 1987 and 40 (97%) of 41 patient s culture-positive between 1996 and 2000 were infected with the same genomo var III strain. Transfer of a colonized patient from Center A to Center B w as associated with an increase in B cepacia complex infection in Center B, all of which was with the Center A dominant strain. This strain, designated PHDC, lacks both B cepacia epidemic strain and cblA markers. Conclusions: B cepacia complex strains may remain endemic in CF treatment c enters for many years. Responsible bacterial and host factors and optimal i nfection control measures to prevent inter-patient spread remain to be iden tified.