Comparative safety and efficacy of autogenous vaccine administrated by different routes against furunculosis caused by Aeromonas salmonicida sub. salmonicida in large Rainbow trout (Oncorhynchus mykiss).

The development and growth of fish farming are hindered by viral and bacterial infectious diseases, which necessitate effective disease control measures. Furunculosis, primarily caused by Aeromonas salmonicida, stands out as a significant bacterial disease affecting salmonid fish farms, particularly rainbow trout. Vaccination has emerged as a crucial tool in combating this disease. The objective of this experiment was to assess and compare the efficacy and duration of different vaccine protocols against furunculosis in large trout under controlled rearing conditions, utilizing single and booster administrations via intraperitoneal, oral, and immersion routes. Among the various vaccination protocols tested, only those involving intraperitoneal injection, administered at least once, proved truly effective in preventing the expression of clinical signs of furunculosis and reducing mortality rates. A single intraperitoneal administration provided protection for up to 2352°-days, equivalent to approximately 5 months in water at 16 °C. However, intraperitoneal vaccination may lead to reduced growth in the fish due to resultant intraperitoneal adhesions. Additionally, protocols incorporating booster doses via intraperitoneal injection demonstrated efficacy regardless of the administration route of the primary vaccination. Nevertheless, the use of booster vaccinations via the intraperitoneal route did not confer any significant advantage over a single intraperitoneal injection in terms of efficacy.

Time effect of experimental infection on Rainbow trout (Oncorhynchus mykiss) by immersion with Aeromonas salmonicida subsp. salmonicida.

Furunculosis caused by Aeromonas salmonicida subsp salmonicida (Ass) is a medically and economically important bacterial disease in salmonid farms that requires therapeutic measures to prevent and control the disease. Evaluation of the effectiveness of traditional measures such as antibiotics or vaccines usually requires infecting fish experimentally. The objective of this study is to develop a method of infectious challenge of large (250-g) Rainbow trout by immersion close to natural infection conditions. We compare mortality, morbidity and anti-Ass antibody production of Rainbow trout following different bathing times (2, 4, 8 and 24 h) at a final bacterial concentration of 106 CFU/mL. One hundred sixty fish divided in five groups corresponding to the 4 bathing times and the non-challenged group were studied. The 24 h contact duration resulted in the infection of all fish, with a mortality rate of 53.25%. The challenged fish developed acute infection with symptoms and lesions (inappetance, altering of swimming behaviour, presence of boils) similar to those observed in furunculosis, and produced antibodies against the bacterium at 4 weeks after challenging, in contrast with the non-challenged group.

Reprocessing of flexible endoscopes and endoscopic accessories used in gastrointestinal endoscopy: Position Statement of the European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastroenterology Nurses and Associates (ESGENA) - Update 2018.

This Position Statement from the European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastroenterology Nurses and Associates (ESGENA) sets standards for the reprocessing of flexible endoscopes and endoscopic devices used in gastroenterology. An expert working group of gastroenterologists, endoscopy nurses, chemists, microbiologists, and industry representatives provides updated recommendations on all aspects of reprocessing in order to maintain hygiene and infection control.

Prevention of multidrug-resistant infections from contaminated duodenoscopes: Position Statement of the European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastroenterology Nurses and Associates (ESGENA).

Patients should be informed about the benefits and risks of endoscopic retrograde cholangiopancreatography (ERCP)Only specially trained and competent personnel should carry out endoscope reprocessing.Manufacturers of duodenoscopes should provide detailed instructions on how to use and reprocess their equipment.In the case of modifications to their equipment, manufacturers should provide updated instructions for use.Detailed reprocessing protocols based on the manufacturer's instructions for use should clearly lay out the different reprocessing steps necessary for each endoscope model.Appropriate cleaning equipment should be used for duodenoscopes in compliance with the manufacturer's instructions for use. Only purpose-designed, endoscope type-specific, single-use cleaning brushes should be used, to ensure optimal cleaning. As soon as the endoscope is withdrawn from the patient, bedside cleaning should be performed, followed by leak testing, thorough manual cleaning steps, and automated reprocessing, in order to: · Remove debris from external and internal surfaces;. · Prevent any drying of body fluids, blood, or debris;. · Prevent any formation of biofilms.. In addition to the leak test, visual inspection of the distal end as well as regular maintenance of duodenoscopes should be performed according to the manufacturer's instructions for use, in order to detect any damage at an early stage.The entire reprocessing procedure in endoscope washer-disinfectors (EWDs) should be validated according to the European and International Standard, EN ISO 15883. Routine technical tests of EWDs should be performed according to the validation reports.Microbiological surveillance of a proportion of the department's endoscopes should be performed every 3 months, with the requirement that all endoscopes used in the unit are tested at least once a year.In the case of suspected endoscopy-related infection, the relevant device (e. g., endoscope, EWD) should be taken out of service until adequate corrective actions have been taken. Outbreaks should be managed by a multidisciplinary team, including endoscopy, hygiene, and microbiology experts, manufacturers, and regulatory bodies, according to national standards and/or laws. In the case of suspected multidrug-resistant organism (MDRO) outbreaks, close cooperation between the endoscopy unit and the clinical health provider is essential (including infection control departments and hospital hygienists).

ESGE-ESGENA technical specification for process validation and routine testing of endoscope reprocessing in washer-disinfectors according to EN ISO 15883, parts 1, 4, and ISO/TS 15883-5.

1 Prerequisites. The clinical service provider should obtain confirmation from the endoscope washer-disinfector (EWD) manufacturer that all endoscopes intended to be used can be reprocessed in the EWD. 2 Installation qualification. This can be performed by different parties but national guidelines should define who has the responsibilities, taking into account legal requirements. 3 Operational qualification. This should include parametric tests to verify that the EWD is working according to its specifications. 4 Performance qualification. Testing of cleaning performance, microbiological testing of routinely used endoscopes, and the quality of the final rinse water should be considered in all local guidelines. The extent of these tests depends on local requirements. According to the results of type testing performed during EWD development, other parameters can be tested if local regulatory authorities accept this. Chemical residues on endoscope surfaces should be searched for, if acceptable test methods are available. 5 Routine inspections. National guidelines should consider both technical and performance criteria. Individual risk analyses performed in the validation and requalification processes are helpful for defining appropriate test frequencies for routine inspections.

Endoscope reprocessing: Retrospective analysis of 90,311 samples.

Background and study aims The contamination level of ready-to-use endoscopes published in the literature varies from 0.4 % to 49.0 %. Unfortunately, the comparison and the interpretation of these results are quite impossible, given the limited number of samples and sites included and the differences observed between sampling, culturing methods, and interpretation criteria. Methods The objective of this retrospective study was to analyze the results of 90,311 endoscope samples collected between 2004 and 2021 in 490 private or public hospitals in France. Results Through the full test period, the mean ratio of endoscopes at the action level was 12.6 % (19.5 % including alert level). Of the endoscopy units, 23.0 % had a ratio of compliant endoscopes ≤ 70.0 %. The overall microbial quality of gastroscopes, duodenoscopes, and colonoscopes is improving year by year, whereas an opposite trend is observed for ultrasound endoscopes and bronchoscopes. In 2021, following French guidelines, 13.0 % of the endoscopes should have been quarantined and 8.1 % were at the alert level, meaning that the contamination level of 21.1 % of the endoscopes exceeded what was defined as a maximum acceptable value. Conclusions This study demonstrates that additional efforts, including implementation of microbial surveillance strategies using a standardized sampling method and periodic observational audits, must be made to improve the overall microbiological quality of endoscopes and reduce the risk associated with their use.

Comparison of the sporicidal activity of a UV disinfection process with three FDA cleared sterilants.

BACKGROUND: Endocavitary probes are semi-critical devices and must undergo, at least, high level disinfection (HLD) between uses. Therefore, they should be high level disinfected between uses (i.e., with a product/process that kills all forms of microbial life; bacteria, fungi, mycobacteria, and virus, and in some countries, a demonstrated potential for sporicidal activity). In this study, the sporicidal activity of three common Food and Drug Administration cleared sterilants (CIDEX OPA Solution, SPOROX II Sterilizing and Disinfection Solution and CIDEX Activated Dialdehyde Solution) was compared with the sporicidal activity of an ultraviolet disinfection technology (Hypernova Chronos, Germitec) against Bacillus subtilis ATCC 19659 spores spread on silicone flat carriers in the presence of inorganic and organic soil. RESULTS: The results indicate that the UV disinfection process presented within a 35 seconds exposure time a sporicidal efficacy substantially higher than the chemical sterilants used according to manufacturer instructions for HLD. CONCLUSIONS: This study demonstrated that even if it cannot be tested/approved as a sterilant according to AOAC 966.04, the UV unit is much more effective than usual Food and Drug Administration approved chemical HLD products to kill spores in real use conditions. This finding questions the relevancy of evaluating product efficacy within extended conditions giving results that could mislead users to select the most effective HLD product/process for the reprocessing of their medical devices.

A prospective, multicenter, clinical study of duodenoscope contamination after reprocessing.

OBJECTIVE: Several clinical procedures utilize duodenoscopes, which are processed for reuse after the procedures are completed. However, infection outbreaks due to improper duodenoscope processing occur frequently. To address this, we aimed to assess the contamination rates of duodenoscopes after reprocessing in nonoutbreak settings. DESIGN AND SETTING: Prospective study in 16 clinical sites in the United States. METHODS: We sampled and cultured reprocessed duodenoscopes following the FDA/CDC/ASM guideline; "Duodenoscope Surveillance Sampling and Culturing - Reducing the Risks of Infection." High-concern (HC) organisms were those highly associated with disease, including gram-negative rods, Staphylococcus aureus, Staphylococcus lugdunensis, ß-hemolytic Streptococcus, Enterococcus spp, and yeasts. We evaluated duodenoscopes with ≥1 CFU of organisms after reprocessing. The reprocessing environments were also sampled and cultured. RESULTS: We assessed 859 newer-model (NM) duodenoscopes (TJF-Q180V) and 850 older-model (OM) duodenoscopes (TJF-160F/VF); of these, 35 NM samples (4.1%) and 56 OM samples (6.6%) were contaminated with HC organisms. We detected and classified the HC organisms as gastrointestinal (45.4%), human origin (16.7%), environmental (24.1%), waterborne (13.0%), and unidentified (0.9%). CONCLUSIONS: We detected an overall HC contamination rate of 5.3% in nonoutbreak settings. Although the relationship between endoscopic contamination and the occurrence of infections remains unclear, attempts should continue to be made to further reduce contamination rates. Additional improvements to the manufacturer's instructions for use, human factors during the reprocessing procedure, ongoing training programs, cleanliness of reprocessing environments, and the design of the distal end of the duodenoscope should be considered.

Antimicrobial Susceptibility Profiles and Resistance Genes in Genus Aeromonas spp. Isolated from the Environment and Rainbow Trout of Two Fish Farms in France.

This study presents the occurrence and abundance of Aeromonas antibiotic-resistant bacteria (ARB) and genes (ARGs) isolated from water, biofilm and fish in two commercial trout farms before and one week after flumequine treatment. Wild (WT) and non-wild (NWT) strains were determined for quinolones (flumequine, oxolinic acid and enrofloxacin), oxytetracycline (OXY), florfenicol (FFN), trimethoprim-sulfamethoxazole (TMP) and colistin (COL), and pMAR (presumptive multi-resistant) strains were classified. Forty-four ARGs for the mentioned antibiotics, ß-lactams and multi-resistance were quantified for 211 isolates. BlaSHV-01, mexF and tetE were the dominant ARGs. A greater occurrence and abundance of tetA2, sul3, floR1, blaSHV-01 and mexF were observed for NWT compared to WT. The occurrence of pMAR and NWT Aeromonas for quinolones, OXY, FFN, TMP, COL and ARGs depended on the Aeromonas origin, antibiotic use and the presence of upstream activities. Our results revealed the impact of a flumequine treatment on Aeromonas present on a fish farm through an increase in NWT and pMAR strains. The link between fish and their environment was shown by the detection of identical ARB and ARGs in the two types of samples. There appears to be a high risk of resistance genes developing and spreading in aquatic environments.