Genomic Analysis of Mycobacterium abscessus Complex Isolates Collected in Ireland between 2006 and 2017.

Members of the Mycobacterium abscessus complex (MABC) are multidrug-resistant nontuberculous mycobacteria and cause opportunistic pulmonary infections in individuals with cystic fibrosis (CF). In this study, genomic analysis of MABC isolates was performed to gain greater insights into the epidemiology of circulating strains in Ireland. Whole-genome sequencing (WGS) was performed on 70 MABC isolates that had been referred to the Irish Mycobacteria Reference Laboratory between 2006 and 2017 across nine Irish health care centers. The MABC isolates studied comprised 52 isolates from 27 CF patients and 18 isolates from 10 non-CF patients. WGS identified 57 (81.4%) as M. abscessus subsp. abscessus, 10 (14.3%) as M. abscessus subsp. massiliense, and 3 (4.3%) as M. abscessus subsp. bolletii Forty-nine (94%) isolates from 25 CF patients were identified as M. abscessus subsp. abscessus, whereas 3 (6%) isolates from 2 CF patients were identified as M. abscessus subsp. massiliense Among the isolates from non-CF patients, 44% (8/18) were identified as M. abscessus subsp. abscessus, 39% (7/18) were identified as M. abscessus subsp. massiliense, and 17% (3/18) were identified as M. abscessus subsp. bolletii WGS detected two clusters of closely related M. abscessus subsp. abscessus isolates that included isolates from different CF centers. There was a greater genomic diversity of MABC isolates among the isolates from non-CF patients than among the isolates from CF patients. Although WGS failed to show direct evidence of patient-to-patient transmission among CF patients, there was a predominance of two different strains of M. abscessus subsp. abscessus Furthermore, some MABC isolates were closely related to global strains, suggesting their international spread. Future prospective real-time epidemiological and clinical data along with contemporary MABC sequence analysis may elucidate the sources and routes of transmission among patients infected with MABC.

Evaluation of screening risk and nonrisk patients for methicillin-resistant Staphylococcus aureus on admission in an acute care hospital.

BACKGROUND: Screening for methicillin-resistant Staphylocccus aureus (MRSA) is advocated as part of control measures, but screening all patients on admission to hospital may not be cost-effective. OBJECTIVE: Our objective was to evaluate the additional yield of screening all patients on admission compared with only patients with risk factors and to assess cost aspects. METHODS: A prospective, nonrandomized observational study of screening nonrisk patients ≤72 hours of admission compared with only screening patients with risk factors over 3 years in a tertiary referral hospital was conducted. We also assessed the costs of screening both groups. RESULTS: A total of 48 of 892 (5%) patients was MRSA positive; 28 of 314 (9%) during year 1, 12 of 257 (5%) during year 2, and 8 of 321 (2%) during year 3. There were significantly fewer MRSA-positive patients among nonrisk compared with MRSA-risk patients: 4 of 340 (1%) versus 44 of 552 (8%), P ≤ .0001, respectively. However, screening nonrisk patients increased the number of screening samples by 62% with a proportionate increase in the costs of screening. A backward stepwise logistic regression model identified age > 70 years, diagnosis of chronic pulmonary disease, previous MRSA infection, and admission to hospital during the previous 18 months as the most important independent predictors to discriminate between MRSA-positive and MRSA-negative patients on admission (94.3% accuracy, P < .001). CONCLUSION: Screening patients without risk factors increased the number of screenings and costs but resulted in few additional cases being detected. In a hospital where MRSA is endemic, targeted screening of at-risk patients on admission remains the most efficient strategy for the early identification of MRSA-positive patients.

Sixteen years' surveillance of surgical sites in an Irish acute-care hospital.

OBJECTIVE: To report a program of continuous surveillance of surgical-site infections (SSIs) using basic surveillance methods. DESIGN: Analysis of routine prospective surveillance data. SETTING: Two hospitals in Ireland (300 and 350 beds) that merged and moved to a new 650-bed hospital in 1987. PATIENTS: 59,335 surgical sites of postoperative patients. INTERVENTIONS: Surgical sites were surveyed by one infection control nurse and SSI rates were produced for selected operations and surgical services. The program was conducted in general accordance with the 1999 HICPAC guidelines, but differed in surveillance strategy. Operations were limited to two to three risk classifications, assigned by the infection control nurse. RESULTS: The overall SSI rate was 4.5%, with 2.4% in clean surgery. Apart from increases in the 3rd, 4th, 13th, and 14th years, rates remained relatively stable during the 16 years. Few significant decreases in SSI rates in surgical services or specific operations were shown, apart from the following: vascular surgery, 8.1% to 5% between the first 8 years and the last 8 years; general surgery services, 9% to 5%, and gynecology, 15.8% to 1.7%, both in the first year compared with in subsequent years; and gastric operations, 21% to 4.3% between the first year and the second year. Organ/space infection was identified in 0.5% of 17,804 operations, including 0.4% meningitis after neurosurgical procedures, 3% graft infections after vascular bypass operations, and 0.2% intra-abdominal infections after abdominal surgery. CONCLUSIONS: With the use of basic principles of surveillance and modest resources, procedure-specific SSI rates were produced, with little significant change during the 16 years. Despite limitations in case-finding, risk stratification, feedback, and surveillance methods, the overall SSI rates were comparable with other published data.