Naturally acquired infection of humans with a marine mammal-associated Brucella sp. has only been reported once previously in a study describing infections of two patients from Peru. We report the isolation and characterization of a strain of Brucella from a New Zealand patient that appears most closely related to strains previously identified from marine mammals. The isolate was preliminarily identified as Brucella suis using conventional bacteriological tests in our laboratory. However, the results profile was not an exact match, and the isolate was forwarded to four international reference laboratories for further identification. The reference laboratories identified the isolate as either B. suis or B. melitensis by traditional bacteriological methods in three laboratories and by a molecular test in the fourth laboratory. Molecular characterization by PCR, PCR-restriction fragment length polymorphism, and DNA sequencing of the bp26 gene; IS711; the omp genes omp25, omp31, omp2a, and omp2b; IRS-PCR fragments I, III, and IV; and five housekeeping gene fragments was conducted to resolve the discrepant identification of the isolate. The isolate was identified to be closely related to a Brucella sp. originating from a United States bottlenose dolphin (Tursiops truncatus) and common seals (Phoca vitulina).Brucellosis is an important zoonotic disease of humans, causing a variety of vague symptoms including undulant fever, fatigue, malaise, joint pain, myalgia, depression, and anorexia (22). Chronic sequelae and recrudescence decades after initial infection also occur. Brucella may be transmitted from animals to humans by direct contact with infected animals, ingestion of infected food products, and inhalation of aerosols. Four species of Brucella are the primary causes of infection in humans. Brucella melitensis is highly infectious and is transmitted from sheep and goats, B. abortus is transmitted from cattle, B. suis is transmitted from pigs and, infrequently, B. canis is transmitted from dogs. Other species of Brucella have been rarely or not reported to infect humans.There are only two reports in the literature of humans infected with marine mammal strains of Brucella. One report was of a laboratory worker who displayed symptoms consistent with brucellosis (4). The infection was confirmed by a positive serological response, isolation, and PCR-restriction fragment length polymorphism (RFLP) identification of a marine Brucella strain. Two patients originating from Peru and diagnosed with neurobrucellosis were also confirmed to be infected with marine mammal strains of Brucella by isolation, PCR, and DNA sequencing (41). The two Peruvian patients were not laboratory workers, and the infection was naturally acquired.Serological evidence and isolation of brucellae have been reported from a variety of marine mammals on numerous occasions from locations in the northern hemisphere. The serological prevalence ranges from 0 to 38% for cetaceans, pinnipeds, and mustelids (6,24,26,29,32,34,43). The largest studies of 1,855 ...

Vibriosis, a hemorrhagic septicemic disease caused by the bacterium Vibrio anguillarum, is an important bacterial infection in Danish sea-reared rainbow trout. Despite of vaccination, outbreaks still occur, likely because the vaccine is based on V. anguillarum strains from abroad/other hosts than rainbow trout. Information about the genetic diversity of V. anguillarum specifically in Danish rainbow trout, is required to investigate this claim. Consequently, the aim of the present investigation was to sequence and to characterize a collection of 44 V. anguillarum strains obtained primarily from vibriosis outbreaks in Danish rainbow trout. The strains were sequenced, de novo assembled, and the genomes examined for the presence of plasmids, virulence, and acquired antibiotic resistance genes. To investigate the phylogeny, single nucleotide polymorphisms were identified, and the pan-genome was calculated. All strains carried tet(34) encoding tetracycline resistance, and 36 strains also contained qnrVC6 for increased fluoroquinolone/quinolone resistance. But interestingly, all strains were phenotypic sensitive to both oxytetracycline and oxolinic acid. Almost all serotype O1 strains contained a pJM1-like plasmid and nine serotype O2A strains carried the plasmid p15. The distribution of virulence genes was rather similar across the strains, although evident variance among serotypes was observed. Most significant, almost all serotype O2 and O3 strains, as well as the serotype O1 strain without a pJM1-like plasmid, carried genes encoding piscibactin biosynthesis. Hence supporting the hypothesis, that piscibactin plays a crucial role in virulence for pathogenic strains lacking the anguibactin system. The phylogenetic analysis and pan-genome calculations revealed great diversity within V. anguillarum. Serotype O1 strains were in general very similar, whereas considerable variation was found among serotype O2A strains. The great diversity within the V. anguillarum serotype O2A genomes is most likely the reason why vaccines provide good protection from some strains, but not from others. Hopefully, the new genomic data and knowledge provided in this study might help develop an optimized vaccine against V. anguillarum in the future to reduce the use of antibiotics, minimize economic losses and improve the welfare of the fish.

The occurrence of bacteria belonging to Pasteurellaceae in the oral cavity of captive marine mammals was investigated using culture and subsequent geno- and phenotypic characterization and phylogenetic analyses. A total of 89 bacterial isolates from pinnipeds tentatively classified with the family Pasteurellaceae were further characterized by phylogenetic analysis of rpoB gene sequences, which showed that the isolates investigated formed five distinct groups. Four strains from California sea lions (Zalophus californianus) made up group I, which was classified with Pasteurella canis. Group II comprised four strains from harbor seals (Phoca vitulina) and grey seals (Halichoerus grypus) classified with Pasteurella stomatis. Group III consisted of 28 strains, isolated from harbor and gray seals and represented Bisgaardia genomospecies 1. Two strains from a harbor and a grey seal, group IV, were classified with Bisgaardia hudsonensis. Fifty-two strains from northern fur seals (Callorhinus ursinus), walruses (Odobenus rosmarus), and California and Steller sea lions (Eumetopias jubatus) formed group V and represented Otariodibacter oris. No Pasteurellaceae isolates were obtained from cetaceans, but Pasteurellaceae were isolated from all sampled pinnipeds. On the basis of these results, it is very likely that Pasteurellaceae bacteria represent a part of the normal oral flora in pinnipeds.

The occurrence of bacteria belonging to the family Pasteurellaceae in the oral cavity of captive Tasmanian devils (Sarcophilus harrisii) was investigated using phenotypic and subsequent genotypic characterization and phylogenetic analyses. A total of 62 bacterial isolates obtained from Tasmanian devils, tentatively classified with the family Pasteurellaceae, were further characterized by phylogenetic analysis of rpoB gene sequence similarity, which showed that the isolates investigated formed five distinct groups. A total of 15 strains formed a novel genus-like group within Pasteurellaceae. Thirty-six strains grouped with the type strain of Frederiksenia canicola. Five strains clustered with the type strain of Pasteurella multocida . Interestingly, four of the P. multocida-like strains were β-hemolytic when incubated on blood agar, which is atypical for this genus. Five strains grouped with a 100% rpoB similarity with Pasteurella dagmatis. Finally, a single strain showed 97.1% resemblance to Haemophilus haemoglobinophilus. The results demonstrate that Tasmanian devils are hosting a variety of bacterial taxa affiliated with the family of Pasteurellaceae as part of their oral microflora.

Eighty-two Pasteurellaceae isolates from marsupials characterized by phylogenetic analysis of rpoB gene sequences formed five distinct groups. Twenty-one strains from long-nosed potoroos ( Potorous tridactylus apicalis), spotted-tailed quolls ( Dasyurus maculatus), and eastern quolls ( Dasyurus viverrinus) made up group 1, which classified with Frederiksenia canicola. Group 2, 15 strains from Tasmanian devils ( Sarcophilus harrisii), common wombats ( Vombatus ursinus), common ring-tailed possums ( Pseudocheirus peregrinus), and eastern quolls, grouped with Pasteurella multocida. Three strains from koalas ( Phascolarctos cinereus) formed group 3 and clustered with Lonepinella koalarum. Group 4, 13 common wombat strains only distantly related to other Pasteurellaceae, probably represent a new genus. Finally, 29 strains from Tasmanian devils, spotted-tailed quolls and eastern quolls formed group 5 and clustered with 15 previously described Tasmanian devil strains, belonging to a yet unnamed Pasteurellaceae taxon. The results strongly indicate that Pasteurellaceae bacteria represent a part of the normal oral microbiota in marsupials.