Outbreak Of Carbapenem-resistant Acinetobacter Baumannii Research Articles

Evolution, control and success of combination therapy with Ampicilin-sulbactam/Ceftazidime-Avibactam during a Carbapenem-Resistant Acinetobacter baumannii outbreak in burn Intensive Care Unit.

We present our findings on interpatient transmission, epidemic control measures, and the outcomes of a series of ten critically ill burn patients who were either colonized or infected with carbapenem-resistant Acinetobacter baumannii (CRAB). None of the five infected patients achieved clinical cure, and all experienced relapses. Microbiological failure was observed in 40% of the infected patients. The isolated CRAB strains were found to carry blaOXA-23 and armA resistance genes. Despite the lack of clinical cure, all five infected patients survived and were discharged from the Burn Intensive Care Unit.

Hospital outbreak of Carbapenem-resistant acinetobacter baumannii in the context of local facility transmission

Carbapenem-resistant Acinetobacter baumannii are of increasing concern in the health care setting. We describe a cluster of 9 cases in hospitalized patients over a 3-month period that reflected ongoing community transmission from high-risk facilities. Robust surveillance and knowledge of local epidemiology are critical to mitigating onward transmission in the health care setting.

Carbapenem-resistant Acinetobacter baumannii Outbreak in a COVID-19 Isolation Ward and Successful Outbreak Control with Infection Control Measures.

Even amid the coronavirus disease-19 (COVID-19) pandemic, the spread of multidrug-resistant bacteria and infection control are still important tasks. After recognizing the carbapenem-resistant Acinetobacter baumannii (CRAB) outbreak that occurred in the isolation room for COVID-19, we would like to introduce what infection control measures were implemented to eradicate it. All COVID-19 patients with CRAB in any specimen admitted to the COVID-19 isolation ward of the tertiary hospital in South Korea from October to November 2021 were analyzed. During the outbreak, 23 patients with COVID-19 and CRAB infections were identified. The index case was an 85-year-old female referred from a long-term care facility. CRAB was identified in sputum culture in most patients (91.3%). The CRAB outbreak occurred mainly in the rooms around the index case. Environmental cultures on the floor, air inlet, air outlet, and window frame of the rooms were performed. The antimicrobial resistance patterns of CRAB from patients and the environment were identical; whole-genome sequencing analyses revealed isolated clonality. Infection control measures with enhanced environmental cleaning using 1,000 ppm sodium hypochlorite and phenolic compounds, enhanced hand hygiene, additional education, and mandatory additional gowning and gloving of COVID-19 personal protective equipment (PPE) were applied on 29 October. No CRAB infection cases occurred from 2 November for two weeks. In addition to applying PPE and COVID-19 precautions in COVID-19 isolation wards, adhering to strict contact precautions along with environmental control can help prevent the spread of multidrug-resistant bacteria.

Fanny pack transmission of carbapenem-resistant Acinetobacter baumannii

Background: Carbapenem-resistant Acinetobacter baumannii (CRAB) is a gram-negative coccobacillus that has garnered notoriety as a formidable cause of nosocomial infection with significant mortality. This organism poses a significant threat due to its multitude of resistance mechanisms and ability to endure within the environment. In the summer of 2022, a 350-bed acute-care hospital identified an outbreak of CRAB among critically ill patients in the intensive care unit (ICU) and intensive nursing care unit (INCU). Here, we report actions taken to contain the outbreak and to identify a common environmental source. Methods: In total, 7 nosocomial CRAB infection cases were identified by the infection prevention team between July and September 2022. A multidisciplinary team reviewed the cases using relevant medical history and available microbial susceptibilities. Clinical culture sites include 1 PICC tip, 1 urine sample, 1 peritoneal fluid samples, 5 wounds, and 1 sputum sample. Of 7 infections, 6 met the criteria for hospital onset, with an average time to infection from admission of 61 days. We quickly initiated universal contact precautions in the ICU and INCU for 6 weeks, enhanced daily cleaning of high-touch surfaces, provided staff and visitor education, conducted adenosine triphosphate (ATP) testing, collected observations, and performed selective environmental culturing based on observations. Results: In total, 71 environmental specimens were collected for culture. All were negative with the exception of 1 isolate obtained from the fanny pack of a wound-care nurse that was positive for CRAB. Also, 4 available patient isolates and the environmental isolate were sent to New York State Department of Health Wadsworth Center (NYSDOH Wadsworth) for genome sequencing, and relation to the same cluster was confirmed. Of 7 isolates, 6 were confirmed to express the blaOXA-23 resistance mechanism (1 was not available for testing). Subsequently, chart review identified that a wound-care nurse had had contact with all 7 patients within 30 days of their infections. Conclusions: After initiation of the described action plan, no further transmission was identified in the ICU or INCU. Real-time observation and environmental culturing was critical in identifying the epidemiological link, and this finding speaks to the ability of this organism to persist on a surface for a substantial length of time. Fanny pack use for transport of patient-care supplies was identified as a high-risk practice due to the inability to be properly disinfected between rooms and limited laundering. Fanny packs are no longer permitted in clinical spaces at this facility.Disclosures: None

Molecular Epidemiological Investigation and Management of Outbreak Caused by Carbapenem-Resistant Acinetobacter baumannii in a Neonatal Intensive Care Unit.

The present study describes an epidemiological investigation into a carbapenem-resistant Acinetobacter baumannii (CRAB) outbreak, which had occurred in a neonatal intensive care unit (NICU), and the subsequent strengthening of infection control interventions. Upon the onset of the outbreak, existing infection control interventions were reviewed, and a set of containment measures were instituted. All CRAB isolates were characterized in terms of antimicrobial susceptibility testing and their genetic relatedness. The investigation process identified gaps within the NICU's existing infection control measures, which had likely resulted in the outbreak. CRAB was isolated from nine preterm infants: five colonized and four infected. All five colonized patients were discharged well. However, three out of four of the infected infants died. Outbreak investigation and genomic subtyping of environmental swabs revealed that mini syringe drivers shared between patients and a sink in the milk preparation room had served as CRAB reservoirs with possible transmission via the hands of healthcare workers. Implementation of immediate actions such as reinforcement of hand hygiene practices, intensified environmental cleaning, geographical cohorting, reviewing of milk handling practices and sink management protocol had resulted in no further CRAB isolation. The CRAB outbreak in the NICU underlines the importance of consistent compliance with infection-control interventions. Integration of epidemiological and microbiological data, together with comprehensive preventive measures, successfully brought the outbreak to a halt.

Genomic Characterization of Carbapenem-Resistant Acinetobacter baumannii (CRAB) in Mechanically Ventilated COVID-19 Patients and Impact of Infection Control Measures on Reducing CRAB Circulation during the Second Wave of the SARS-CoV-2 Pandemic in Milan, Italy.

COVID-19 has significantly affected hospital infection prevention and control (IPC) practices, especially in intensive care units (ICUs). This frequently caused dissemination of multidrug-resistant organisms (MDROs), including carbapenem-resistant Acinetobacter baumannii (CRAB). Here, we report the management of a CRAB outbreak in a large ICU COVID-19 hub Hospital in Italy, together with retrospective genotypic analysis by whole-genome sequencing (WGS). Bacterial strains obtained from severe COVID-19 mechanically ventilated patients diagnosed with CRAB infection or colonization between October 2020 and May 2021 were analyzed by WGS to assess antimicrobial resistance and virulence genes, along with mobile genetic elements. Phylogenetic analysis in combination with epidemiological data was used to identify putative transmission chains. CRAB infections and colonization were diagnosed in 14/40 (35%) and 26/40 (65%) cases, respectively, with isolation within 48 h from admission in 7 cases (17.5%). All CRAB strains belonged to Pasteur sequence type 2 (ST2) and 5 different Oxford STs and presented blaOXA-23 gene-carrying Tn2006 transposons. Phylogenetic analysis revealed the existence of four transmission chains inside and among ICUs, circulating mainly between November and January 2021. A tailored IPC strategy was composed of a 5-point bundle, including ICU modules' temporary conversion to CRAB-ICUs and dynamic reopening, with limited impact on ICU admission rate. After its implementation, no CRAB transmission chains were detected. Our study underlies the potentiality of integrating classical epidemiological studies with genomic investigation to identify transmission routes during outbreaks, which could represent a valuable tool to ensure IPC strategies and prevent the spread of MDROs. IMPORTANCE Infection prevention and control (IPC) practices are of paramount importance for preventing the spread of multidrug-resistant organisms (MDROs) in hospitals, especially in the intensive care unit (ICU). Whole-genome sequencing (WGS) is seen as a promising tool for IPC, but its employment is currently still limited. COVID-19 pandemics have posed dramatic challenges in IPC practices, causing worldwide several outbreaks of MDROs, including carbapenem-resistant Acinetobacter baumannii (CRAB). We present the management of a CRAB outbreak in a large ICU COVID-19 hub hospital in Italy using a tailored IPC strategy that allowed us to contain CRAB transmission while preventing ICU closure during a critical pandemic period. The analysis of clinical and epidemiological data coupled with retrospective genotypic analysis by WGS identified different putative transmission chains and confirmed the effectiveness of the IPC strategy implemented. This could be a promising approach for future IPC strategies.

The COVID-19 Pandemic Sparked Off a Large-Scale Outbreak of Carbapenem-Resistant Acinetobacter baumannii from the Endemic Strains at an Italian Hospital.

Acinetobacter baumannii is a nosocomial pathogen that poses a serious threat due to the rise of incidence of multidrug-resistant (MDR) strains. During the COVID-19 pandemic, MDR A. baumannii clones have caused several outbreaks worldwide. Here, we describe a detailed investigation of an MDR A. baumannii outbreak that occurred at Policlinico San Matteo (Pavia, Italy). A total of 96 A. baumannii strains, isolated between January and July 2020 from 41 inpatients (both SARS-CoV-2 positive and negative) in different wards, were characterized by phenotypic and genomic analyses combining Illumina and Nanopore sequencing. Antibiotic susceptibility testing revealed that all isolates were resistant to carbapenems, and the sequence analysis attributed this to the carbapenemase gene blaOXA-23. Virulence factor screening unveiled that all strains carried determinants for biofilm formation, while plasmid analysis revealed the presence of two plasmids, one of which was ~100 kbp long and encoded a phage sequence. A core genome-based phylogeny was inferred to integrate outbreak strain genomes with background genomes from public databases and the local surveillance program. All strains belonged to the globally disseminated sequence type 2 (ST2) clone and were mainly divided into two clades. Isolates from the outbreak clustered with surveillance isolates from 2019, suggesting that the outbreak was caused by two strains that were already circulating in the hospital before the start of the pandemic. The intensive spread of A. baumannii in the hospital was enhanced by the extreme emergency situation of the first COVID-19 pandemic wave that resulted in reduced attention to infection prevention and control practices. IMPORTANCE The COVID-19 pandemic, especially during the first wave, posed a great challenge to the hospital management and generally promoted nosocomial pathogen dissemination. MDR A. baumannii can easily spread and persist for a long time on surfaces, causing outbreaks in health care settings. Infection prevention and control practices, epidemiological surveillance, and microbiological screening are fundamental in order to control such outbreaks. Here, we sequenced the genomes of 96 isolates from an outbreak of MDR A. baumannii strains using both short- and long-read technology in order to reconstruct the outbreak events in fine detail. The sequence data demonstrated that two endemic clones of MDR A. baumannii were the source of this large hospital outbreak during the first COVID-19 pandemic wave, confirming the effect of COVID-19 emergency disrupting the protection provided by the use of the standard prevention procedures.

1217. An outbreak of carbapenem-resistant Acinetobacter baumannii in an isolation ward for COVID-19 and successful outbreak control with infection control measures

Abstract Background The superinfection of multidrug-resistant bacteria is an important complication in critically ill COVID-19 patients. An outbreak of carbapenem-resistant Acinetobacter baumannii (CRAB) occurred in an isolation ward for COVID-19. We performed an outbreak investigation, and successfully controlled the outbreak with the enhanced environmental cleaning and additional gowning and gloving. Methods This study analyzed all COVID-19 patients with CRAB in any specimen, who admitted to an isolation ward for COVID-19 of a tertiary hospital in South Korea from October to November 2021. Results During the outbreak period, a total of 23 patients with COVID-19 and CRAB were identified (Figure 1). Index case was 85-year old female patient who was referred from a long-term care facility. The mean age of cases was 72.9 and 14 (60.9%) patients were male. In most patients (91.3%), CRAB were identified in sputum culture, two were identified in blood culture at initial, and four patients were identified in sputum and blood culture at the same time. Most of the patients were applying high flow nasal cannula (26.1%) or mechanical ventilation (60.9%)(Table1). As shown in figure2, CRAB outbreak occurred mainly in the wards around the index case, and in particular, environmental culture was carried out in the area marked with a rectangle. CRAB was cultured on the floor, air inlet, air outlet, and window frame of the ward except for wards 3305 and 3319. Phenotypic antimicrobial resistance patterns of CRAB isolates from patients and environment were identical, and additional whole genome sequencing analyses are ongoing to find the clonality of isolates. We applied the infection control measures with the enhanced environmental cleaning using sodium hypochlorite(NaClO) 1000ppm and phenolic compounds more than twice a day, enhanced hand hygiene, and additional gowning and gloving over personal protective equipment (PPE) mandatory for COVID-19 on 29th October. No additional CRAB cases occurred since 2nd November 2021 for two weeks. Figure 1.Daily number of cases with carbapenem-resistant Acinetobacter baumannii during outbreak periodFigure 2.Floor plan of isolation ward with Acinetobacter baumannii outbreak Conclusion Even when PPEs and precautions for COVID-19 are applied to isolation wards for COVID-19, it is helpful for preventing transmission of multidrug-resistant bacteria to apply additional contact precautions and environmental cleaning. Disclosures All Authors: No reported disclosures.

Clean clothes or dirty clothes? Outbreak investigation of carbapenem-resistant Acinetobacter baumannii related to laundry contamination through multilocus sequence typing (MLST).

To investigate the source in an outbreak of carbapenem-resistant Acinetobacter baumannii (CRA) in a general hospital due to contamination of a laundry evaporative cooler and the laundry environment using multilocus sequence typing (MLST). For CRA culture, clinical samples were collected from infected patients and close contacts, and environmental sampling was performed in patient surroundings and laundry facilities. MLST was used for the molecular typing of representative CRA isolates. Bacterial isolates with identical sequence types were considered epidemiologically linked and attributable to the same source. OXA genes in Acinetobacter baumannii were detected using polymerase chain reaction (PCR). In total, 58 patients were affected in this outbreak. The mean patient age was 75.3, and 50% were female. The most common diagnoses at admission were skin and soft-tissue infection (n = 12, 20.7%) and pneumonia (n = 12, 20.7%). OXA-23 was positive in 64.7% of isolates. A CRA isolate from the evaporative cooler in the laundry was identical to that of 11 patients across 3 wards, belonging to ST345. Isolates from 3 laundry linen racks were identical to those of 7 patients from 3 wards, classified as ST1145. Isolates found on another linen rack and a pajama shelf were identical to isolates from 3 other patients from 2 wards, belonging to ST2207. There was no significant difference between sequence type distributions of clinical and environmental isolates (P = .12), indicating high likelihood of CRA originating from the same source. MLST confirmed that contamination of the laundry evaporative cooler and surrounding environment caused a polyclonal CRA hospital outbreak. Hospital laundry is an important area for infection control and outbreak investigations of CRA.

The impact of COVID-19 pandemic on nosocomial multidrug-resistant bacterial bloodstream infections and antibiotic consumption in a tertiary care hospital.

We investigated the change in the epidemiology of nosocomial bloodstream infections (BSIs) caused by multidrug-resistant bacteria during Coronavirus Disease (COVID-19) and antibiotic consumption rates at a pandemic hospital and at the Oncology Hospital which operated as COVID-19-free on the same university campus. Significant increases in the infection density rate (IDRs) of BSIs caused by carbapenem-resistant Acinetobacter baumannii (CRAB) and ampicillin-resistant Enterococcus faecium (ARE) were detected at the pandemic hospital, whereas carbapenem-resistant Klebsiella pneumoniae BSIs were increased at the non-pandemic Oncology Hospital. Pulsed field gel electrophoresis showed a polyclonal outbreak of CRAB in COVID-19 intensive care units. Antibiotic consumption rates were increased for almost all antibiotics, and was most significant for meropenem at both of the hospitals. Increased IDRs of CRAB and ARE BSIs as well as an increased consumption rate of broad-spectrum antibiotics emphasize the importance of a multimodal infection prevention strategy combined with an active antibiotic stewardship program.

Outbreak investigation of CRAB at an acute-care hospital ICU during the COVID-19 pandemic–Chicago, Illinois, March 2020–September 2021

Background: Carbapenem-resistant Acinetobacter baumannii (CRAB) is primarily associated with hospital-acquired infections and is an urgent public health threat due to its ability to contaminate the environment and cause severe disease. In 2019, Illinois began pilot surveillance for CRAB requiring select laboratories to submit specimens for molecular characterization. On July 17, 2020, the Chicago Department of Public Health (CDPH) was notified of an increase in CRAB infections in a 20-bed ICU at an acute-care hospital in Chicago (hospital A) during the initial COVID-19 surge. We summarize the outbreak investigation findings and infection control recommendations. Methods: Clinical cultures were collected from patients in hospital A, and CRAB-positive isolates were sent to the Wisconsin State Laboratory of Hygiene for mechanism of resistance and antibiotic susceptibility testing. On-site assessments and remote follow-ups were conducted by CDPH infection preventionists to evaluate infection control practices including environmental cleaning, hand hygiene compliance, and use of personal protective equipment (PPE). The Illinois Department of Public Health and CDPH summarized the testing results, facilitated a containment response, and provided recommendations for infection control. Results: From March 18, 2020, to September 30, 2021, 56 patients with CRAB infections were identified from hospital A, and 33 (59%) of these cases were pan-nonsusceptible. Most specimen sources were sputum (n = 30, 54%), followed by blood (n = 13, 23%), urine (n = 6, 11%) and other (n = 7, 13%). Among isolates with mechanism testing (n = 54), 45 (83%) were positive for OXA-24/40 and 9 (17%) were positive for OXA-23. Of the CRAB-positive patients, 28 (50%) were previously positive for SARS-CoV-2. To date, 25 of these patients (45%) have been discharged and 31 (55%) have died. Two onsite visits and 7 remote-assistance sessions were conducted as part of the investigation. In response to increased COVID-19 hospitalizations, hospital A moved to crisis-capacity PPE use and encountered staffing shortages, which led to compromised infection control measures. Cleaning agents (Quat disinfectant cleaner) were also found to be ineffective against CRAB and required long contact times. Conclusions: In response to the CRAB outbreak at hospital A, CDPH recommended that the hospital stop crisis-capacity protocols for PPE, conduct admission screening and point-prevalence testing for CRAB, implement a hand hygiene campaign, and use an EPA-registered List K product for environmental cleaning. These recommendations were implemented in May 2021, and no CRAB cases have been reported since July 2021. To reduce CRAB transmission during the pandemic, facility leadership must commit resources to educate staff on effective infection control practices including conventional use of PPE, appropriate cleaning agents, and improved hand hygiene.Funding: NoneDisclosures: None

Clonal spread of ArmA- and OXA-23-coproducing Acinetobacter baumannii International Clone 2 in Brazil during the first wave of the COVID-19 pandemic.

Introduction. Carbapenem-resistant Acinetobacter baumannii (CRAB) is the primary pathogen causing hospital-acquired infections. The spread of CRAB is mainly driven by the dissemination of resistant clones, and in Latin America, International Clones IC-1 (also known as clonal complex CC1), IC-4 (CC15) and IC-5 (CC79) are the most prevalent.Gap Statement. There are no documented outbreaks of CRAB International Clone 2 (IC-2) reported in Brazil.Aim. To describe a large outbreak of CRAB caused by the uncommon IC-2 in a Brazilian COVID-19 hospital.Methodology. From May 2020 to May 2021, 224 patients infected or colonized with CRAB were identified in a single hospital; 92 % of them were also infected with SARS-CoV-2. From these patients, 137 isolates were recovered and subjected to antimicrobial susceptibility testing, PCR analysis and molecular typing. Whole-genome sequencing and downstream analysis were carried out on a representative isolate (the first available isolate).Results. In 76 % of the patients, a single OXA-23-producing CRAB IC-2 was identified. All the isolates were susceptible to polymyxin B, but highly resistant (>95 %) to aminoglycosides, fluoroquinolones and beta-lactams. Genomic analysis revealed that the representative isolate also carried the 16S rRNA Methylase ArmA, which was detected for the first time in this species in Brazil.Conclusion. We report the rapid spread of an emerging CRAB clone responsible for causing a large outbreak in a hospital in Brazil, a country with predominance of other CRAB clones. Continuous and prospective surveillance is warranted to evaluate the impact of this clone in Brazilian hospital settings.

Management of a Major Carbapenem-Resistant Acinetobacter baumannii Outbreak in a French Intensive Care Unit While Maintaining Its Capacity Unaltered.

We describe bundle measures implemented to overcome a protracted carbapenem-resistant Acinetobacter baumannii (CRAB) outbreak in an 18-bed trauma Intensive Care Unit (ICU) at Strasbourg University Hospital, a tertiary referral center in France. Outbreak cases were defined by a positive CRAB sample with OXA-23 profile during or after ICU say. To sustain the capacity of the busy trauma ICU, infection control bundles were purposely selected to control the outbreak without closing the ICU. During the outbreak, from May 2015 to January 2019, 141 patients were contaminated by CRAB, including 91 colonized and 50 infected patients. The conventional infection and prevention control (IPC) measures implemented included weekly active surveillance of patients’ samples, enhancement of environmental cleaning, interventions to improve hand hygiene compliance and antibiotic stewardship with audits. Supplemental measures were needed, including environmental samplings, health care workers’ (HCWs) hand sampling, chlorhexidine body-washing, relocation of the service to implement Airborne Disinfection System (ADS), replication of crisis cells, replacement of big environmental elements and improvement of HCW organization at the patient’s bedside. The final measure was the cohorting of both CRAB patients and HCW caring for them. Only the simultaneous implementation of aggressive and complementary measures made it possible to overcome this long-lasting CRAB epidemic. Facing many CRAB cases during a rapidly spreading outbreak, combining simultaneous aggressive and complementary measures (including strict patients and HCW cohorting), was the only way to curb the epidemic while maintaining ICU capacity.

Containment of a carbapenem-resistant Acinetobacter baumannii complex outbreak in a COVID-19 intensive care unit

BackgroundA carbapenem-resistant Acinetobacter baumannii outbreak in the COVID intensive care unit of a community hospital was contained using multidrug resistant organism guidelines. The purpose of this study is to report on an outbreak investigation and containment strategy that was used, and to discuss prevention strategy.MethodsA multidisciplinary approach contained the spread of infection. Strategies implemented included consultation with experts, screening, and reversal of personal protective equipment conservation. Ensuring infection control best practices are maintained remain important efforts to reduce the spread of multidrug resistant organisms.ResultsFive patients with carbapenem-resistant Acinetobacter baumannii were identified from routine clinical cultures within one week and one patient was identified from active surveillance cultures.DiscussionPersonal protective equipment conservation, strategies to prevent health care personnel exposure, and patient surge staffing protocols may have increased the likelihood of multidrug resistant organism transmission. Environmental and behavioral infection control regulations with effective administrative guidance, active surveillance cultures, and antimicrobial stewardship are critical to prevent future outbreaks.ConclusionsAfter outbreak containment strategies were implemented, no additional patients were identified with carbapenem-resistant Acinetobacter baumannii. Conventional infection prevention and control strategies were re-instituted. A multidisciplinary approach with continued focus on hand hygiene, environmental cleaning, and correct use of personal protective equipment needs to be put in place to successfully contain and prevent the spread of carbapenem resistant infections.

Antibacterial effect of acetic acid during an outbreak of carbapenem-resistant Acinetobacter baumannii in an ICU (II).

Acetic acid (AA) has been commonly used in medicine as an antiseptic agent for the past 6000 years. This study evaluated the antibacterial effect of AA during an outbreak in an intensive care unit (ICU) facility in Baja California Sur, México. Thirty-five environmental samples were collected, subsequently, disinfection with AA (4%) was performed, and two days later the same areas were sampled inside the ICU facility. Carbapenem-resistant A. baumannii (CRAB) was detected with loop-mediated isothermal amplification assay (Garciglia-Mercado et al. companion paper), targeting blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, blaOXA-58-like, blaIMP and blaVIM genes. CRAB isolates before and after disinfection were compared by PFGE. Eighteen (54.5%) and five (14.3%) of thirty-five environmental samples were identified as Acinetobacter baumannii before and after disinfection, respectively, showing a significant decrease of 85.7% (p < 0.05) both by Loop-mediated isothermal amplification (LAMP) and polymerase chain reaction (PCR). Furthermore, the presence of blaOXA-23-like and blaOXA-58-like genes significantly decreased (p < 0.05) both by LAMP and PCR methods. PFGE genotype showed high similarity among CRAB isolates before and after disinfection, suggesting wide clonal dissemination in the ICU facility. This study demonstrated the novel application of AA with the LAMP assays developed for detecting CRAB. AA promises to be a cheap and efficacious disinfectant alternative to both developed and especially developing countries, preventing the spread of this organism in the environment and to other susceptible patients in health care settings.

Wall painting following terminal cleaning with a chlorine solution as part of an intervention to control an outbreak of carbapenem-resistant Acinetobacter baumannii in a neurosurgical intensive care unit in Israel

BackgroundTo describe the use of wall painting as part of an intervention to control an outbreak of carbapenem-resistant Acinetobacter baumannii (CRAB). MethodsAn interrupted time-series analysis was performed analyzing an intervention in a neurosurgical intensive care unit (NSICU) and an inpatient hematology department in a tertiary level medical center in Israel. The intervention involved wall painting using a water based acrylic paint following patient discharge and terminal cleaning with sodium troclosene as part of an infection control bundle for an outbreak of CRAB in a NSICU and concurrent outbreaks of carbapenem-resistant Enterobacteriaceae (CRE) colonization/infection in the same NSICU and the hematology department. ResultsBetween January 2013 and December 2018, 122 patients hospitalized in the NSICU were identified with new CRAB colonization/infection. The median incidence in the periods prior to/post intervention were 2.24/1000 HD (interquartile range [IQR] 0.84–2.90/1000) vs. 0/1000 HD (IQR 0–0.49/1000), respectively. Poisson regression indicated a decrease of 92% in the CRAB incidence following the intervention onset (relative risk [RR] 0.080, 95% confidence interval [CI] 0.037–0.174, p < 0.001). Forty-seven patients in the NSICU and 110 in the hematology department were colonized/infected with CRE in the same time period; a significant change was not observed following the start of the intervention in either department (for NSICU RR 1.236, 95% CI 0.370–4.125, p = 0.731; for hematology RR 0.658, 95% CI 0.314–1.378, p = 0.267). ConclusionsA. baumannii is able to survive on environmental surfaces despite decontamination efforts; wall-painting as part of a bundle may be a successful infection control measure.

Adaptations of carbapenem resistant Acinetobacter baumannii (CRAB) in the hospital environment causing sustained outbreak

Introduction. Carbapenem resistance in Acinetobacter baumannii (A. baumannii) is an emerging global threat.Gap statement. The adaptation strategies of A. baumannii for this emergence as a nosocomial pathogen has been less studied.Aim. This prospective study analysed a sustained outbreak of carbapenem resistant Acinetobacter baumannii (CRAB) in the intensive care unit (ICU) with reference to antimicrobial resistance and virulence in the colonizing and pathogenic isolates under carbapenem stress.Results. The CRAB isolates from initial and sustained outbreak were found harbouring multiple carbapenemase genes. These genes included bla OXA-23 ,bla IMP, bla VIM and bla NDM. From NICU environment three phenotypically carbapenem susceptible isolates were found carrying bla OXA-23, bla IMP, bla VIM genes. Prior imipenem therapy was one of the risk factors (P=0.0016). The outbreak was polyclonal. Under imipenem stress, outbreak isolates showed no loss of carbapenemase genes against stress free conditions (23.7±1.33 days). Biofilm formation increased with imipenem concentration, with outbreak isolates producing highest biomass. While the pathogens showed a slow growth rate on imipenem exposure, the colonisers grew rapidly (P <0.0001).Methods. Sustained outbreak of CRAB was identified in the ICU (July 2015 to December 2017). Risk factors for acquisition of CRAB was studied. A. baumannii isolates were also collected from the environments of ICU and neonatal ICU (NICU) and blood cultures of septic neonates. Isolates were characterized based on antimicrobial susceptibility, genetic profile, integrons carriage and clonality. Biofilm formation and growth kinetics were studied under varying carbapenem stress.Conclusion. Intense carbapenem exposure in the ICU facilitates persistence of CRAB by several adaptations causing sustained outbreaks.

Genomic surveillance, characterization and intervention of a polymicrobial multidrug-resistant outbreak in critical care

Background. Infections caused by carbapenem-resistant Acinetobacter baumannii (CR-Ab) have become increasingly prevalent in clinical settings and often result in significant morbidity and mortality due to their multidrug resistance (MDR). Here we present an integrated whole-genome sequencing (WGS) response to a persistent CR-Ab outbreak in a Brisbane hospital between 2016–2018. Methods. A. baumannii, Klebsiella pneumoniae, Serratia marcescens and Pseudomonas aeruginosa isolates were sequenced using the Illumina platform primarily to establish isolate relationships based on core-genome SNPs, MLST and antimicrobial resistance gene profiles. Representative isolates were selected for PacBio sequencing. Environmental metagenomic sequencing with Illumina was used to detect persistence of the outbreak strain in the hospital. Results. In response to a suspected polymicrobial outbreak between May to August of 2016, 28 CR-Ab (and 21 other MDR Gram-negative bacilli) were collected from Intensive Care Unit and Burns Unit patients and sent for WGS with a 7 day turn-around time in clinical reporting. All CR-Ab were sequence type (ST)1050 (Pasteur ST2) and within 10 SNPs apart, indicative of an ongoing outbreak, and distinct from historical CR-Ab isolates from the same hospital. Possible transmission routes between patients were identified on the basis of CR-Ab and K. pneumoniae SNP profiles. Continued WGS surveillance between 2016 to 2018 enabled suspected outbreak cases to be refuted, but a resurgence of the outbreak CR-Ab mid-2018 in the Burns Unit prompted additional screening. Environmental metagenomic sequencing identified the hospital plumbing as a potential source. Replacement of the plumbing and routine drain maintenance resulted in rapid resolution of the secondary outbreak and significant risk reduction with no discernable transmission in the Burns Unit since. Conclusion. We implemented a comprehensive WGS and metagenomics investigation that resolved a persistent CR-Ab outbreak in a critical care setting.

Whole-Genome Sequencing for Investigating a Health Care-Associated Outbreak of Carbapenem-Resistant Acinetobacter baumannii.

Carbapenem-resistant Acinetobacter baumannii (CRAB) outbreaks in hospital settings challenge the treatment of patients and infection control. Understanding the relatedness of clinical isolates is important in distinguishing outbreak isolates from sporadic cases. This study investigated 11 CRAB isolates from a hospital outbreak by whole-genome sequencing (WGS), utilizing various bioinformatics tools for outbreak analysis. The results of multilocus sequence typing (MLST), single nucleotide polymorphism (SNP) analysis, and phylogenetic tree analysis by WGS through web-based tools were compared, and repetitive element polymerase chain reaction (rep-PCR) typing was performed. Through the WGS of 11 A. baumannii isolates, three clonal lineages were identified from the outbreak. The coexistence of blaOXA-23, blaOXA-66, blaADC-25, and armA with additional aminoglycoside-inactivating enzymes, predicted to confer multidrug resistance, was identified in all isolates. The MLST Oxford scheme identified three types (ST191, ST369, and ST451), and, through whole-genome MLST and whole-genome SNP analyses, different clones were found to exist within the MLST types. wgSNP showed the highest discriminatory power with the lowest similarities among the isolates. Using the various bioinformatics tools for WGS, CRAB outbreak analysis was applicable and identified three discrete clusters differentiating the separate epidemiologic relationships among the isolates.

An outbreak of carbapenem-resistant Acinetobacter baumannii in a COVID-19 dedicated hospital

SummaryWe describe an outbreak of carbapenem-resistant Acinetobacter baumannii (CRAB) in a COVID-19 dedicated hospital. The suspected mechanism of transfer was an environmental source that persisted despite evacuation and terminal cleaning of the entire hospital, and transmitted through healthcare workers' hands or equipment. This outbreak demonstrates that practices to prevent the spread of multidrug-resistant organisms must not be neglected during the COVID-19 pandemic.