Fish are commonly infected with non‐tuberculous mycobacteria (NTM), which should be regarded as potential pathogens when handling aquarium fish and equipment. This study examined 107 aquarium fish ...from pet shops. Cultivation of the fish samples using different selective media was conducted for identification of NTM. Isolates were identified using the GenoType Mycobacterium common mycobacteria and additional species assays, sequencing of the 16S rRNA and rpoB genes, and real‐time PCR assay for identification of Mycobacterium (M.) marinum. Among the investigated fish, 79.4% (85/107) were positive for mycobacteria, with 8.2% (7 of 85) having two mycobacterial species present. Among the positive fish, the common pathogens M. marinum, Mycobacterium fortuitum (M. fortuitum group) and Mycobacterium chelonae were identified in approx. 90% of fish and other NTM species in 10%, including Mycobacterium peregrinum/septicum, Mycobacterium gordonae, Mycobacterium arupense, Mycobacterium kansasii, Mycobacterium ulcerans and Mycobacterium setense. The well‐known human pathogen M. marinum was present in 10.6% of the positive fish (9 of 85). The species of mycobacteria identified in the study are not only recognized as aquarium fish pathogens, but can also cause pathology in humans. Microbiological and clinical communities should therefore be sensitized to the role of NTM in infections associated with exposure to aquarium fish.
Epidemiological studies on
Mycobacterium avium are requisite for revealing infection sources and disease transmission. They are based upon genotyping methods like RFLP and MIRU–VNTR. In our study, ...MIRU–VNTR typing was applied to 121 previously RFLP typed
M. avium field isolates to compare the discriminatory power of both methods. The applicability of MIRU–VNTR typing was studied for isolates from a limited geographic area, namely 41
M. avium subsp.
avium and 80
M. avium subsp.
hominissuis isolates. Among the former, exhibiting 12 IS
901 RFLP types, five MIRU–VNTR types were found with discriminatory index (
DI) of 0.716. Among the latter, exhibiting 56 IS
1245 RFLP types, 18 MIRU–VNTR types were found with
DI of 0.866. Concomitant use of both methods increased
DI to 0.981 and 0.995, respectively. MIRU–VNTR typing employing the selected markers provided discernible discrimination among
M. avium subsp.
hominissuis isolates, but more discriminative markers are needed for
M. avium subsp.
avium isolates.
Thirty-five aquarium fish were investigated for the presence of mycobacteria by culture and molecular methods. The following species were examined: goldfish Carassius auratus auratus, guppy Poecilia ...reticulata, 4 three-spot gourami Trichogaster trichopterus, dwarf gourami Colisa lalia, Siamese fighting fish Betta splendens, freshwater angelfish Pterophyllum scalare, African cichlid fish Cichlidae spp., cichlid fish Microgeophagus altispinosus, cichlid fish Pseudotropheus lombardoi, blue streak hap Labidochromis caeruleus, sterlet Acipenser ruthenus, southern platyfish Xiphophorus maculatus, and catfish Corydoras spp. Isolates of mycobacteria were obtained in 29 cases (82.9%). Two specimens were positive using Ziehl-Neelsen (ZN) staining, but the cultivation failed. Four specimens were both ZN- and culture-negative. On the basis of GenoType Mycobacterium assay (Hain Life-science) and restriction enzyme analysis of the amplified products (PCR-RFLP), 23 isolates (79.3%) were identified: 7 as Mycobacterium fortuitum, 6 as M. gordonae, 6 as M. marinum, 3 as M. chelonae, and 1 as M. peregrinum. Five isolates remained unidentified (Mycobacterium spp.). One case probably represented a mixed infection (M. marinum/M. fortuitum). Since M. marinum infections are also detected in humans, the significance of mycobacteria in aquarium fish should not be overlooked.
In the autumn of 2004, tuberculosis caused by Mycobacterium caprae occurred in a zoo in Slovenia. A dromedary camel (Camelus dromedarius) was killed after a history of progressive emaciation. ...Necropsy findings indicated disseminated tuberculosis, which was confirmed by cultivation of M. caprae. Consequently, a tuberculin skin test was performed in all epidemiologically linked animals and another dromedary camel and six bison (Bison bison) were positive and killed. Mycobacterium caprae was isolated from two bison while M. scrofulaceum and Mycobacterium spp. were found in two other bison, respectively. The second dromedary camel was found to be negative for mycobacteria under both microscopic and culture tests. The isolates were investigated with commercial identification kits, IS6110 PCR, IS6110 restriction fragment length polymorphism analysis, spoligotyping and mycobacterial interspersed repetitive units typing. Genotyping results revealed that the dromedary camel and the two bison were infected by the same M. caprae.
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