Hospital-wide healthcare-associated carbapenemase-producing Enterobacterales outbreak: risks of electric floor scrubbers in catering facilities and kitchens

BACKGROUND

Carbapenemase-producing Enterobacterales (CPE) are associated with poor clinical outcomes and can spread rapidly in healthcare settings. Environmental reservoirs are increasingly recognized as playing an important part in some nosocomial outbreaks.

AIM

To describe the investigation and control of a CPE outbreak, lasting several years, across two separate hospital sites within one organization.

METHODS

Investigation of multiple ward-level CPE cross-transmissions with a number of sporadic cases. Environmental sampling of ward environments, catering facilities and electric floor scrubbers was undertaken.

FINDINGS

Eleven patients over a 19-month period were identified as carrying healthcare-associated New Delhi metallo-beta-lactamase (NDM)-producing Enterobacter cloacae, and a further patient carried NDM Escherichia coli. E. cloacae isolates were indistinguishable on pulsed-field gel electrophoresis typing, supporting acquisition with a single point source. Environmental sampling found contamination of the electric floor scrubbers used for cleaning the hospital catering facilities and in the associated toilets. Standard outbreak response measures achieved control of ward outbreaks. Sporadic cases and hospital-wide cross-transmission were controlled after interventions on the central food-handling unit and by decommissioning affected floor scrubbers. Electric floor scrubbers were found to have the potential to disperse Gram-negative bacteria into the surrounding environment under experimental conditions.

CONCLUSION

This outbreak report demonstrates that catering facilities and kitchens can be involved in widespread healthcare outbreaks of enteric organisms. This is also the first report of the potential role of electric floor scrubbers in causing significant environmental contamination with CPE which may indicate a role in nosocomial transmission.

Outbreak of invasive group A streptococcus: investigations using agar settle plates detect perineal shedding from a healthcare worker

BACKGROUND

Outbreaks of group A streptococcus (GAS) infections may occur in healthcare settings. Transmission to patients is sometimes linked to colonized healthcare workers (HCWs) and/or a contaminated environment.

AIM

To describe the investigation and control of an outbreak of healthcare-associated GAS on an elderly care medical ward, over six months.

METHODS

Four patients developed septicaemia due to GAS infection without a clinically obvious site of infection. The outbreak team undertook an investigation involving a retrospective review of GAS cases, prospective case finding, HCW screening and environmental sampling using both swabs and settle plates. Immediate control measures included source isolation and additional cleaning of the ward environment with a chlorine disinfectant and hydrogen peroxide.

FINDINGS

Prospective patient screening identified one additional patient with throat GAS carriage. Settle plate positivity for GAS was strongly associated with the presence of one individual HCW on the ward, who was subsequently found to have GAS perineal carriage. Contamination of a fabric-upholstered chair in an office adjacent to the ward, used by the HCW, was also detected. In total, three asymptomatic HCWs had throat GAS carriage and one HCW had both perineal and throat carriage. All isolates were typed as emm 28.

CONCLUSION

This is the first outbreak report demonstrating the use of settle plates in a GAS outbreak investigation on a medical ward, to identify the likely source of the outbreak. Based on this report we recommend that both throat and perineal sites should be sampled if HCW screening is undertaken during an outbreak of GAS. Fabric, soft furnishings should be excluded from clinical areas as well as any adjacent offices because pathogenic bacteria such as GAS may contaminate this environment.

Investigating the impact of clinical anaesthetic practice on bacterial contamination of intravenous fluids and drugs

Syringes (N = 426), ventilator machine swabs (N = 202) and intravenous (IV) fluid administration sets (N = 47) from 101 surgical cases were evaluated for bacterial contamination. Cultures from the external surface of syringe tips and syringe contents were positive in 46% and 15% of cases, respectively. The same bacterial species was cultured from both ventilator and syringe in 13% of cases, and was also detected in the IV fluid administration set in two cases. A significant association was found between emergency cases and contaminated syringes (odds ratio 4.5, 95% confidence interval 1.37-14.8; P = 0.01). Other risk factors included not using gloves and failure to cap syringes.

Outbreak of invasive group A streptococcus infection: contaminated patient curtains and cross-infection on an ear, nose and throat ward

BACKGROUND

Outbreaks of group A streptococcus (GAS) infections may occur in healthcare settings and have been documented in surgical, obstetrics and gynaecology, and burns units. The environment may serve as a reservoir and facilitate transmission via contaminated equipment.

AIM

To describe the investigation and control of an outbreak of healthcare-associated GAS infection on an ear, nose and throat (ENT) ward in a tertiary referral centre.

METHODS

Two patients with laryngeal cancer developed invasive GAS infection (bacteraemia) with associated tracheostomy wound cellulitis within a 48 h period. The outbreak team undertook an investigation involving a retrospective review of GAS cases, prospective case finding, healthcare worker screening and sampling of patient curtains. Immediate control measures included source isolation, a thorough rolling clean with a chlorine-based disinfectant and hydrogen peroxide decontamination of patient equipment.

FINDINGS

Prospective patient screening identified one additional patient with carriage of GAS from a tracheostomy wound swab. Staff screening identified one healthcare worker who acquired GAS during the outbreak and who subsequently developed pharyngitis. Environmental sampling demonstrated that 10 out of 34 patient curtains on the ward were contaminated with GAS and all isolates were typed as emm-1.

CONCLUSION

This is the first outbreak report to demonstrate patient curtains as potential source for GAS cross-transmission, with implications in relation to hand hygiene and frequency of laundering. Based on this report we recommend that during an outbreak of GAS infection all patient curtains should be changed as part of the enhanced decontamination procedures.

First UK evaluation of an automated ultraviolet-C room decontamination device (Tru-D™)

Tru-D™ is an automated room disinfection device that uses ultraviolet-C radiation to kill micro-organisms. The device was deployed in six side-rooms and an operating theatre. In a cleaned, unoccupied operating theatre, Tru-D eradicated all organisms from the environment. Using artificially seeded Petri dishes with meticillin-resistant Staphylococcus aureus, multi-resistant acinetobacter and vancomycin-resistant enterococci, the mean log10 reductions were between three and four when used at 22,000μWs/cm(2) reflected dose. The device was easy to transport and utilize, and able to disinfect rooms rapidly. This appears to be a practical alternative technology to other 'no-touch' automated room disinfection systems.