Utilisation de bactériophages pour contrôler les populations de Aeromonas salmonicida résistantes aux antibiotiques

La furonculose, causée par la bactérie Aeromonas salmonicida, représente une des principales causes de mortalité chez les salmonidés d’élevage. L’antibiothérapie constitue l’approche la plus largement répandue pour contrer les effets néfastes de cette maladie. Cependant, le développement de bactéries résistantes aux antibiotiques représente un problème de plus en plus préoccupant. La présente recherche a visé à explorer une nouvelle option pour lutter contre la furonculose, soit la possibilité d’utiliser des bactériophages comme moyen de prévention pour contrôler les populations de A. salmonicida. La sensibilité de 19 souches de A. salmonicida, résistantes à aucun, un, deux ou trois antibiotiques, a été évaluée vis‑à‑vis de 12 bactériophages. Les résultats ont montré que les souches de A. salmonicida résistantes aux antibiotiques utilisés dans l’industrie piscicole canadienne sont aussi sensibles à de nombreux bactériophages, tout comme des souches sensibles aux antibiotiques. Il serait donc possible d’envisager un traitement préventif à base de bactériophages pour lutter contre la furonculose chez les salmonidés d’élevage.Aquaculture represents an increasingly important source of food fish worldwide. The aquaculture industry currently produces between 25 and 30% of all seafood for human consumption. In Canada, salmonids (salmon, rainbow trout, arctic char and brook trout) account for the majority of food fish production. Furonculosis involving the bacterium Aeromonas salmonicida is one of the most important infections observed in salmonid farms. An A. salmonicida infection results either in morbidity and mortality with few clinical signs, or in weakened fish with skin ulcers that make them unmarketable for human consumption. The A. salmonicida bacterium uses a number of mechanisms to counteract the natural barrier of the immune system. Bacterial growth is encouraged by an increase in the ambient temperature and in the concentration of organic matter in the water.During recent years, a relationship between therapeutic failures and the development of bacterial resistance to antibiotics has been reported in salmonid farms. This problem is complicated by the fact that only four antibiotics are authorized for the aquaculture industry in Canada. One consequence of this increasing resistance is a renewed interest in alternative therapies and prevention. Bacteriophages (bacterial viruses) may represent one such alternative. In recent decades, interest in bacteriophages as antibacterial agents has been growing in the Americas and in Asia. Some researchers have tried to exploit the potential of bacteriophages to reduce bacterial populations in infections affecting humans, while others have tried to identify uses in veterinary medicine.The overall objective of this research was to explore a new treatment against furonculosis infection based on the use of bacteriophages to inhibit growth of A. salmonicida cells. In this study, we looked at 19 strains of A. salmonicida, resistant to zero, one, two or three antibiotics, and evaluated their sensitivity to 12 bacteriophages. The results showed that the antibiotic-resistant strains were sensitive to as many bacteriophages as were the bacterial strains sensitive to antibiotics. They also showed that all the A. salmonicida strains were sensitive to several bacteriophages and, conversely, that several bacteriophages were effective against all the A. salmonicida strains. It may thus be possible to consider a preventive treatment using bacteriophages to fight against furonculosis in salmonid farms

Das weisse Hirsch von Ludwig Uhland. Als Melodram mit Klavierbegleitung komponiert von Carl Reinecke. Op. 111 No. 3.

6 p. 34 cm. For spoken voice and piano. In binders collection. Binder’s title: Melodramen und Declamationen

Zoonotic Babesia: A scoping review of the global evidence.

BACKGROUND:Babesiosis is a parasitic vector-borne disease of increasing public health importance. Since the first human case was reported in 1957, zoonotic species have been reported on nearly every continent. Zoonotic Babesia is vectored by Ixodes ticks and is commonly transmitted in North America by Ixodes scapularis, the tick species responsible for transmitting the pathogens that also cause Lyme disease, Powassan virus, and anaplasmosis in humans. Predicted climate change is expected to impact the spread of vectors, which is likely to affect the distribution of vector-borne diseases including human babesiosis. METHODS:A scoping review has been executed to characterize the global evidence on zoonotic babesiosis. Articles were compiled through a comprehensive search of relevant bibliographic databases and targeted government websites. Two reviewers screened titles and abstracts for relevance and characterized full-text articles using a relevance screening and data characterization tool developed a priori. RESULTS:This review included 1394 articles relevant to human babesiosis and/or zoonotic Babesia species. The main zoonotic species were B. microti, B. divergens, B. duncani and B. venatorum. Articles described a variety of study designs used to study babesiosis in humans and/or zoonotic Babesia species in vectors, animal hosts, and in vitro cell cultures. Topics of study included: pathogenesis (680 articles), epidemiology (480), parasite characterization (243), diagnostic test accuracy (98), mitigation (94), treatment (65), transmission (54), surveillance (29), economic analysis (7), and societal knowledge (1). No articles reported predictive models investigating the impact of climate change on Babesia species. CONCLUSION:Knowledge gaps in the current evidence include research on the economic burden associated with babesiosis, societal knowledge studies, surveillance of Babesia species in vectors and animal hosts, and predictive models on the impact of climate change. The scoping review results describe the current knowledge and knowledge gaps on zoonotic Babesia which can be used to inform future policy and decision making

Extended Spectrum β-Lactamase-Producing Enterobacterales of Shrimp and Salmon Available for Purchase by Consumers in Canada—A Risk Profile Using the Codex Framework

The extended-spectrum β-lactamase (ESBL)-producing Enterobacterales (ESBL-EB) encompass several important human pathogens and are found on the World Health Organization (WHO) priority pathogens list of antibiotic-resistant bacteria. They are a group of organisms which demonstrate resistance to third-generation cephalosporins (3GC) and their presence has been documented worldwide, including in aquaculture and the aquatic environment. This risk profile was developed following the Codex Guidelines for Risk Analysis of Foodborne Antimicrobial Resistance with the objectives of describing the current state of knowledge of ESBL-EB in relation to retail shrimp and salmon available to consumers in Canada, the primary aquacultured species consumed in Canada. The risk profile found that Enterobacterales and ESBL-EB have been found in multiple aquatic environments, as well as multiple host species and production levels. Although the information available did not permit the conclusion as to whether there is a human health risk related to ESBLs in Enterobacterales in salmon and shrimp available for consumption by Canadians, ESBL-EB in imported seafood available at the retail level in Canada have been found. Surveillance activities to detect ESBL-EB in seafood are needed; salmon and shrimp could be used in initial surveillance activities, representing domestic and imported products

Gedichte /

Mode of access: Internet.SPEC: Gift of Bernhard Uhlendorf, 1980. Bound in green cloth; stamped in gold on spine. Bookplate on inside front cover: "Ex libris Walter Hinrichsen" Three signatures on title-page: "Fredericke Bendz (?), Walter Hinrichsen ... 13 Sept. 1924, and Carl Weise" Pencil notes on rear fly-leaf