Understanding the risks of co-exposures in a changing world: a case study of dual monitoring of the biotoxin domoic acid and Vibrio spp. in Pacific oyster.

Assessing the co-occurrence of multiple health risk factors in coastal ecosystems is challenging due to the complexity of multi-factor interactions and limited availability of simultaneously collected data. Understanding co-occurrence is particularly important for risk factors that may be associated with, or occur in similar environmental conditions. In marine ecosystems, the co-occurrence of harmful algal bloom toxins and bacterial pathogens within the genus Vibrio may impact both ecosystem and human health. This study examined the co-occurrence of Vibrio spp. and domoic acid (DA) produced by the harmful algae Pseudo-nitzschia by (1) analyzing existing California Department of Public Health monitoring data for V. parahaemolyticus and DA in oysters; and (2) conducting a 1-year seasonal monitoring of these risk factors across two Southern California embayments. Existing public health monitoring efforts in the state were robust for individual risk factors; however, it was difficult to evaluate the co-occurrence of these risk factors in oysters due to low number of co-monitoring instances between 2015 and 2020. Seasonal co-monitoring of DA and Vibrio spp. (V. vulnificus or V. parahaemolyticus) at two embayments revealed the co-occurrence of these health risk factors in 35% of sampled oysters in most seasons. Interestingly, both the overall detection frequency and co-occurrence of these risk factors were considerably less frequent in water samples. These findings may in part suggest the slow depuration of Vibrio spp. and DA in oysters as residual levels may be retained. This study expanded our understanding of the simultaneous presence of DA and Vibrio spp. in bivalves and demonstrates the feasibility of co-monitoring different risk factors from the same sample. Individual programs monitoring for different risk factors from the same sample matrix may consider combining efforts to reduce cost, streamline the process, and better understand the prevalence of co-occurring health risk factors.

Duodenoscope-Related Outbreak of a Carbapenem-Resistant Klebsiella pneumoniae Identified Using Advanced Molecular Diagnostics.

Background: Carbapenem-resistant Klebsiella pneumoniae infections are increasingly prevalent in North American hospitals. We describe an outbreak of carbapenem-resistant K. pneumoniae containing the blaOXA-232 gene transmitted by contaminated duodenoscopes during endoscopic retrograde cholangiopancreatography (ERCP) procedures. Methods: An outbreak investigation was performed when 9 patients with blaOXA-232 carbapenem-resistant K. pneumoniae infections were identified at a tertiary care hospital. The investigation included 2 case-control studies, review of duodenoscope reprocessing procedures, and culture of devices. Carbapenem-resistant Enterobacteriacieae (CRE) isolates were evaluated with polymerase chain reaction analysis for carbapenemase genes, and isolates with the blaOXA-232 gene were subjected to whole-genome sequencing and chromosome single-nucleotide polymorphism analysis. On recognition of ERCP as a key risk factor for infection, targeted patient notification and CRE screening cultures were performed. Results: Molecular testing ultimately identified 17 patients with blaOxa-232 carbapenem-resistant K. pneumoniae isolates, including 9 with infections, 7 asymptomatic carriers who had undergone ERCP, and 1 additional patient who had been hospitalized in India and was probably the initial carrier. Two case-control studies established a point-source outbreak associated with 2 specific duodenoscopes. A field investigation of the use, reprocessing, and storage of deuodenoscopes did not identify deviations from US Food and Drug Administration or manufacturer recommendations for reprocessing. Conclusions: This outbreak demonstrated the previously underappreciated potential for duodenoscopes to transmit disease, even after undergoing high-level disinfection according to manufacturers' guidelines.

Departmental quality initiative to establish turnaround times from simulation to treatment.

INTRODUCTION: The process of treatment delivery involves a series of steps from patient evaluation, therapeutic simulation (simulation), followed by dosimetric treatment planning, pre-treatment quality assurance and plan verification, and ultimately treatment delivery. Each step has a strict precedence relationship, requiring the preceding task to be completed prior to the initiation of the next task. The minimum time for a patient to undergo treatment is based on the summation of times of the individual tasks. Nevertheless, patients are often scheduled based on factors that do not directly consider the overall time required to complete these steps. MATERIALS AND METHODS: To better help in scheduling patients and to ensure quality and safety of treatment planning and delivery, we undertook a quality initiative based on team members tabulating time required to complete tasks required for treatment delivery. We established "fastest possible" turnaround times based how quickly a task could be accomplished if there were minimal or no competing obligations, as well as processing times under routine operating conditions. RESULTS: For urgent situations, we found that our center can accommodate treatment within 24 h. For routine plans using 3D conformal radiation, an approximately 1-week turnaround time is needed. For patients being treated with IMRT/VMAT an approximately 2-week turnaround time is needed. CONCLUSIONS: The growing complexity of radiotherapy delivery also requires additional steps which has increased turnaround times from simulation to treatment compared to historical standards. We report our estimates for turnaround time based on plan type and acuity level. While our turnaround times may not be applicable to all centers, we believe that this exercise was helpful to facilitate inter- and intra- departmental communication regarding reasonable start times for patients.