title: Changes in colonization of residents and staff of a long-term care facility and an adjacent acute-care hospital geriatric unit by multidrug-resistant bacteria over a four-year period.
abstract: BACKGROUND
  In 2012 we undertook a screening study for Enterobacteriaceae with extended-spectrum β-lactamases (ESBLs), derepressed or acquired high-level AmpC cephalosporinases, and metallo-β-lactamases (MBLs), and also methicillin-resistant Staphylococcus aureus (MRSA), in a long-term care facility (LTCF1) and the associated acute care hospital geriatric ward in Bolzano, northern Italy. The study followed up an initial survey carried out in LTCF1 in 2008. For comparison, screening in 2012 was extended to a second LTCF.
  
  
  METHODS
  Urine samples and rectal, inguinal, oropharyngeal, and nasal swabs were plated on selective agars. Isolates were typed by pulsed-field gel electrophoresis. Resistance genes and Escherichia coli belonging to ST131 were sought by PCR. Demographic data were collected.
  
  
  RESULTS
  Fewer residents of LTCF1 were colonized with multidrug-resistant (MDR) bacteria in 2012: all MDR organisms, 53.8% vs 74.8% in 2008; ESBL producers, 49.0% vs 64.0% in 2008; MRSA, 13.2% vs 38.7% in 2008; only 2 MBL-producers were isolated in 2012 vs 8 in 2008. Colonization of staff in LTCF1 by MDR bacteria had also decreased (overall 10.5% in 2012 vs 27.5% in 2008). Changed case mixes and risk factors, together with strengthened hygiene measures probably underlie the changes. Colonization proportions in 2012 in LTCF2 were similar to those in LTCF1. By contrast there was no significant change in the proportion of patients colonized by MDR bacteria in the geriatric ward (22.2% in 2008 vs 22.7% in 2012).
  
  
  CONCLUSIONS
  A significant decrease in the proportions of staff and residents of an LTCF colonized by MDR bacteria was observed over a 4-y interval.
authors.affiliation: From the Reparto di Geriatria , Comprensorio Sanitario di Bolzano , Italy.
authors.forename: Albert
authors.initials: A
authors.lastname: March
authors.forename: Richard
authors.initials: R
authors.lastname: Aschbacher
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Pagani
authors.forename: Ferisa
authors.initials: F
authors.lastname: Sleghel
authors.forename: Gertrud
authors.initials: G
authors.lastname: Soelva
authors.forename: Katie L
authors.initials: KL
authors.lastname: Hopkins
authors.forename: Michel
authors.initials: M
authors.lastname: Doumith
authors.forename: Patrizia
authors.initials: P
authors.lastname: Innocenti
authors.forename: Johanna
authors.initials: J
authors.lastname: Burth
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Piazzani
authors.forename: Neil
authors.initials: N
authors.lastname: Woodford
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D004755:Enterobacteriaceae / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D006268:Health Facilities; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008134:Long-Term Care; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D008875:Middle Aged; D058889:Molecular Typing; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D055815:Young Adult