Designed for a pandemic: Mitigating the risk of SARS-CoV-2 transmission through hospital design and infrastructure.

BACKGROUND: To describe the new Royal Adelaide Hospital (RAH) design and infrastructure features that helped mitigate the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission within the hospital during the pre-vaccination and pre-antiviral period. METHOD: The RAH infrastructure, design and initial pandemic response was assessed. A retrospective review of all confirmed or suspected coronavirus disease 2019 (COVID-19) patients admitted from 1 February 2020 to 30 May 2020 was also performed to assess risk of transmission. Outbreak response reports were reviewed to identify episodes of nosocomial COVID-19. RESULTS: Key infrastructure features include single-bed overnight rooms with dedicated bathrooms, creation of pandemic areas accessible only to pandemic staff, and sophisticated air-handling units with improved ventilation. A total of 264 COVID-19 related admission occurred, with 113 confirmed cases and 1579 total cumulative bed days. Despite a limited understanding of SARS-CoV-2 transmission, no vaccination or anti-viral therapy, global shortages of particulate filter respirators and restricted testing during this period, only one probable nosocomial COVID-19 case occurred in a healthcare worker, with no nosocomial cases involving patients. CONCLUSIONS: The RAH design and pandemic features complimented existing infection control interventions and was important in limiting nosocomial spread of SARS-CoV-2.

Environmental dynamics of hospital microbiome upon transfer from a major hospital to a new facility.

BACKGROUND: Infection control is critical to safe hospital care. However, how bacteria within nosocomial environments relate to space utilisation and occupancy remains poorly understood. Our aim was to characterise the hospital microbiome in the context of the closure of a tertiary hospital and the opening of a new facility. METHODS: Environmental swabs were collected from common and inpatient areas in the old and new hospitals during a 12-month transition period. Microbiota characteristics were determined by 16S rRNA gene sequencing and quantitative (q)PCR. Targeted assays were used to detect Methicillin-resistant Staphylococcus aureus (MRSA) and vanB-positive Vancomycin-Resistant Enterococci (VRE). RESULTS: The transition to full occupancy in the new facility was associated with an increase in bacterial load (inpatient areas, 3 months p = 0.001; common areas, 6 months p = 0.039) and a change in microbiota composition (baseline-12 months, PERMANOVA p = 0.002). These changes were characterised by an increase in human microbiota-associated taxa, including Acinetobacter and Veillonella. Closure of the existing facility was associated with a decrease in bacterial load (p = 0.040). Detection of MRSA did not differ significantly between sites. CONCLUSIONS: Occupancy is a major determinant of bacterial dispersion within hospital environments. Steady-state bacterial levels and microbiota composition provide a basis for assessment of infection control measures.

Bloodstream infections in neutropenic patients with haematological malignancies.

BACKGROUND: Patients with haematological malignancies have higher risk of acquiring bloodstream infection (BSI). Neutropenia resulting from cytotoxic chemotherapy is the most common risk factor. Infections can progress rapidly with poor outcomes. Understanding the epidemiology may enable prevention and effective management. We investigated and compared the incidence of BSI amongst patients with haematological malignancies and neutropenia and examined the changing spectrum of organisms, and their antimicrobial profiles. METHODS: BSI data between July 1st 2009 and June 30th 2015 was reviewed. RESULTS: Three hundred and fifty five BSI were identified in 255 neutropenic patients. Acute myeloid leukaemia (AML) accounted for 40%, Non-Hodgkin's lymphoma for 22% and Acute lymphocytic leukaemia (ALL) for 11.8%. A neutrophil count of <500 cells/µL was present in 93.2%. The overall incidence was 5.40 BSI per 1000 Haematology Occupied Bed days (OBD). Viridans streptococci and Enterococcus species were the most predominant Gram-positives. Vancomycin resistant Enterococcus faecium (VRE) emerged as the predominant Enterococcus species during the study period. Escherichia coli was the most predominant Gram-negative and Extended-spectrum beta-lactamases (ESBL) were detected in 7.1% of isolates. Amongst the Enterobacteriaceae and Pseudomonas aeruginosa dual resistance to Piperacillin-tazobactam and Gentamicin was detected in 5.4%. CONCLUSION: Our incidence of BSI was 5.40 per 1000 OBD, however variability in reporting of rates in neutropenic patients with haematological malignancies makes comparison between studies difficult, highlighting the need for rate reporting standardization. The epidemiology of organisms causing BSI has changed over time. There is a trend towards an increasing incidence of VRE and multidrug resistant Gram-negatives.

Burkholderia lata Infections from Intrinsically Contaminated Chlorhexidine Mouthwash, Australia, 2016.

Burkholderia lata was isolated from 8 intensive care patients at 2 tertiary hospitals in Australia. Whole-genome sequencing demonstrated that clinical and environmental isolates originated from a batch of contaminated commercial chlorhexidine mouthwash. Genomic analysis identified efflux pump-encoding genes as potential facilitators of bacterial persistence within this biocide.

Draft Genome Sequences of Two Enterobacter cloacae subsp. cloacae Strains Isolated from Australian Hematology Patients with Bacteremia.

Enterobacter cloacae is a common member of the gut microbiota in healthy individuals. However, it is also an opportunistic pathogen, capable of causing bacteremia. We report the draft genomes of two Enterobacter cloacae subspecies cloacae strains isolated from hematology patients with bacteremia. Both isolates carry genes encoding extended-spectrum ß-lactamases.