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OBJECTIVETo determine the scope, source, and mode of transmission of a multifacility outbreak of extensively drug-resistant (XDR)Acinetobacter baumannii.DESIGNOutbreak investigation.SETTING AND PARTICIPANTSResidents and patients in skilled nursing facilities, long-term acute-care hospital, and acute-care hospitals.METHODSA case was defined as the incident isolate from clinical or surveillance cultures of XDRAcinetobacter baumanniiresistant to imipenem or meropenem and nonsusceptible to all but 1 or 2 antibiotic classes in a patient in an Oregon healthcare facility during January 2012–December 2014. We queried clinical laboratories, reviewed medical records, oversaw patient and environmental surveillance surveys at 2 facilities, and recommended interventions. Pulsed-field gel electrophoresis (PFGE) and molecular analysis were performed.RESULTSWe identified 21 cases, highly related by PFGE or healthcare facility exposure. Overall, 17 patients (81%) were admitted to either long-term acute-care hospital A (n=8), or skilled nursing facility A (n=8), or both (n=1) prior to XDRA. baumanniiisolation. Interfacility communication of patient or resident XDR status was not performed during transfer between facilities. The rare plasmid-encoded carbapenemase geneblaOXA-237was present in 16 outbreak isolates. Contact precautions, chlorhexidine baths, enhanced environmental cleaning, and interfacility communication were implemented for cases to halt transmission.CONCLUSIONSInterfacility transmission of XDRA. baumanniicarrying the rare blaOXA-237was facilitated by transfer of affected patients without communication to receiving facilities.Infect Control Hosp Epidemiol2017;38:1335–1341

Carbapenem antibiotics are among the mainstays for treating infections caused by Acinetobacter baumannii , especially in the Northwest United States, where carbapenem-resistant A. baumannii remains relatively rare. However, between June 2012 and October 2014, an outbreak of carbapenem-resistant A. baumannii occurred in 16 patients from five health care facilities in the state of Oregon. All isolates were defined as extensively drug resistant. Multilocus sequence typing revealed that the isolates belonged to sequence type 2 (international clone 2 [IC2]) and were >95% similar as determined by repetitive-sequence-based PCR analysis. Multiplex PCR revealed the presence of a bla OXA carbapenemase gene, later identified as bla OXA-237 . Whole-genome sequencing of all isolates revealed a well-supported separate branch within a global A. baumannii phylogeny. Pacific Biosciences (PacBio) SMRT sequencing was also performed on one isolate to gain insight into the genetic location of the carbapenem resistance gene. We discovered that bla OXA-237 , flanked on either side by IS Aba1 elements in opposite orientations, was carried on a 15,198-bp plasmid designated pORAB01-3 and was present in all 16 isolates. The plasmid also contained genes encoding a TonB-dependent receptor, septicolysin, a type IV secretory pathway (VirD4 component, TraG/TraD family) ATPase, an integrase, a RepB family plasmid DNA replication initiator protein, an alpha/beta hydrolase, and a BrnT/BrnA type II toxin-antitoxin system. This is the first reported outbreak in the northwestern United States associated with this carbapenemase. Particularly worrisome is that bla OXA-237 was carried on a plasmid and found in the most prominent worldwide clonal group IC2, potentially giving pORAB01-3 great capacity for future widespread dissemination.

To evaluate trends in and risk factors for acquisition of antimicrobial-drug resistant nontyphoidal Salmonella infections, we searched Oregon surveillance data for 2004-2009 for all culture-confirmed cases of salmonellosis. We defined clinically important resistance (CIR) as decreased susceptibility to ampicillin, ceftriaxone, ciprofloxacin, gentamicin, or trimethoprim/sulfamethoxazole. Of 2,153 cases, 2,127 (99%) nontyphoidal Salmonella isolates were obtained from a specific source (e.g., feces, urine, blood, or other normally sterile tissue) and had been tested for drug susceptibility. Among these, 347 (16%) isolates had CIR. The odds of acquiring CIR infection significantly increased each year. Hospitalization was more likely for patients with than without CIR infections. Among patients with isolates that had been tested, we analyzed data from 1,813 (84%) who were interviewed. Travel to eastern or Southeast Asia was associated with increased CIR. Isolates associated with outbreaks were less likely to have CIR. Future surveillance activities should evaluate resistance with respect to international travel.

Carbapenem-resistant Enterobacteriaceae (CRE) are an urgent public health threat. We evaluated the capacity of the Carba NP test to detect carbapenemase production in 206 isolates: 143 Enterobacteriaceae identified by Oregon's CRE surveillance program in 2013 and 63 known carbapenemase-positive organisms. Overall, test sensitivity and specificity were 89% (59/66 isolates; 95% confidence interval [CI], 81 to 97%) and 100% (140/140 isolates; 95% CI, 98 to 100%), respectively. All KPC, NDM-1, VIM, and IMP producers but no (0/7 isolates) OXA-48-like strains were Carba NP positive prior to a post hoc protocol modification. We subsequently incorporated Carba NP into Oregon's CRE screening algorithm.

A multidrug-resistant NDM-1 carbapenamase-producing Escherichia coli sequence type 131 (ST131) organism was obtained from vacuum cleaner dust collected from the home of a case patient. Here, we report the assembly and annotation of its genome.

Objective. We investigated the relationship between Staphylococcus aureus colonization and the use of immunosuppressive therapies in patients with immune-mediated inflammatory diseases (IMIDs). Methods. We prospectively enrolled IMID patients from the rheumatology and dermatology departments of Oregon Health & Science University. At enrolment, we surveyed patients for S. aureus infection risk factors and those using immune-modulating therapies, and evaluated their colonization status with bilateral nares and inguinal fold cultures. Patients were asked to follow up 612 months later for reassessment of colonization status by repeat culture. S. aureus isolates were tested for the presence of methicillin resistance by PCR. Results. We enrolled a total of 548 IMID patients. At enrolment, 219 (40.0%) patients were colonized with S. aureus, of which 27 (12.3%) were methicillin-resistant S. aureus (MRSA). Baseline colonization rates were similar between TNF-a inhibitor users and non-users (40.5% and 39.4%, P = 0.79), but were significantly higher for psoriasis patients compared with those with RA (43.5% and 31.8%, P = 0.02). A total of 384 patients were available for follow-up. Patients who were colonized at enrolment were more likely to be colonized at follow-up if they were treated with TNF-a inhibitors during the study as compared to patients without TNF-a inhibitor exposure [odds ratio (OR) = 2.2 (95% CI 1.1, 4.2), P = 0.02]. Conclusion. Patients with psoriasis are more likely to be colonized with S. aureus than patients with RA. Patients who are colonized with S. aureus are more likely to remain colonized if exposed to TNF-a inhibitors.

We report the microbiological, biochemical, and molecular characterization of an unusual Brucella strain (BO1) isolated from a breast implant wound in a 71-year-old woman with clinical symptoms consistent with brucellosis. Initial phenotypic analysis, including biochemical and antimicrobial susceptibility testing, cellular fatty acid analysis, and molecular analysis based on DNA-DNA reassociation and the presence of multiple copies of IS 711 element suggested that the isolate was a Brucella -like organism, but species determination using microbiological algorithms was unsuccessful. Furthermore, molecular data based on 16S rRNA gene sequencing and multilocus sequence analysis demonstrated that BO1 was an unusual Brucella strain and not closely related to any currently described Brucella species. However, comparison with equivalent sequences in Ochrobactrum spp. confirms that the isolate is much more closely related to Brucella than to Ochrobactrum spp., and thus the isolate likely represents an atypical and novel strain within the genus Brucella .