Interfacility Spread of OXA-23–Producing Carbapenem-Resistant Acinetobacter—Connecticut, 2018–2019

Abstract

Background: Carbapenem-resistant Acinetobacter baumannii (CRAB), a multidrug-resistant gram-negative bacterium, can cause difficult-to-treat infections with mortality in approximately half of CRAB cases. CRAB can spread among healthcare facilities after transfer of an infected or colonized patient. Strategies to limit CRAB spread include adherence to contact precautions, environmental cleaning with bleach, and screening to identify colonized patients. During July–September 2018, the Connecticut Department of Public Health (DPH) worked with an acute-care hospital (hospital A) to contain an outbreak of OXA-23–producing CRAB (OXA-23 is an enzyme that confers resistance to carbapenems). During November 2018–March 2019, statewide CRAB surveillance identified additional cases of related OXA-23–producing CRAB at other healthcare facilities. DPH, Connecticut State Public Health Laboratory (SPHL), and the Antibiotic Resistance Laboratory Network (ARLN) investigated to prevent additional cases. Methods: Since January 2017, CRAB isolates have been routinely sent to SPHL and ARLN for carbapenemase gene detection and whole-genome sequencing (WGS) to determine isolate relatedness. During November 2018–March 2019, DPH collected patient healthcare history for patients with CRAB isolates to identify outbreaks and provide assistance in infection control and prevention to healthcare facilities reporting CRAB cases. Beginning May 2019, DPH and ARLN offered facilities screening to identify patients colonized with OXA-23–producing CRAB. Results: Of 10 OXA-23–producing CRAB isolates reported to DPH during November 2018–March 2019, 3 were closely related to the 9 isolates from hospital A’s outbreak by WGS (single-nucleotide polymorphism difference range, 1–16). One isolate was from a patient who had been admitted to hospital A during July 2018. All 3 patients with CRAB isolates shared a history of residence at long-term–care facility A (LTCF A). Two patients received a CRAB infection diagnosis upon admission to hospital B after transfer from LTCF A. Both LTCF A and hospital B performed environmental cleaning with bleach and placed CRAB-identified patients on contact precautions. LTCF A declined screening patients for CRAB, whereas hospitals B and C, which receive frequent transfers from LTCF A, screened all patients on admission from LTCF A. During May–September 2019, among 6 patients screened, 1 was colonized with OXA-23–producing CRAB and was placed on contact precautions. Conclusions: Transfer of patients who are infected or colonized with CRAB among hospitals and LTCFs can facilitate the regional spread of CRAB. Strategies for containing the spread of carbapenemase-producing organisms include adherence to contact precautions, colonization screening, interfacility communication, and collaboration with public health.Funding: NoneDisclosures: None