| 1. |
- Blomqvist, Maria, et al.
(författare)
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Chlamydia psittaci in birds of prey, Sweden
- 2012
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Ingår i: Infection Ecology and Epidemiology. - 2000-8686. ; 2, s. 8435-
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Tidskriftsartikel (refereegranskat)abstract
- Background: Chlamydia psittaci is an intracellular bacterium primarily causing respiratory diseases in birds but may also be transmitted to other animals, including humans. The prevalence of the pathogen in wild birds in Sweden is largely unknown. Methods: DNA was extracted from cloacae swabs and screened for C. psittaci by using a 23S rRNA gene PCR assay. Partial 16S rRNA and ompA gene fragments were sequence determined and phylogenies were analysed by the neighbour-joining method. Results and conclusion: The C. psittaci prevalence was 1.3% in 319 Peregrine Falcons and White-tailed Sea Eagles, vulnerable top-predators in Sweden. 16S rRNA and ompA gene analysis showed that novel Chlamydia species, as well as novel C. psittaci strains, are to be found among wild birds.
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| 2. |
- Svahn, Stefan, 1977-, et al.
(författare)
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Antimicrobial activity of filamentous fungi isolated from highly antibiotic-contaminated river sediment
- 2012
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Ingår i: Infection Ecology & Epidemiology. - : Informa UK Limited. - 2000-8686. ; 2, s. 11591-
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Tidskriftsartikel (refereegranskat)abstract
- Background:Filamentous fungi are well known for their production of substances with antimicrobial activities, several of which have formed the basis for the development of new clinically important antimicrobial agents. Recently, environments polluted with extraordinarily high levels of antibiotics have been documented, leading to strong selection pressure on local sentinel bacterial communities. In such microbial ecosystems, where multidrug-resistant bacteria are likely to thrive, it is possible that certain fungal antibiotics have become less efficient, thus encouraging alternative strategies for fungi to compete with bacteria.Methods:In this study, sediment of a highly antibiotic-contaminated Indian river was sampled in order to investigate the presence of cultivable filamentous fungi and their ability to produce substances with antimicrobial activity.Results:Sixty one strains of filamentous fungi, predominantly various Aspergillus spp. were identified. The majority of the Aspergillus strains displayed antimicrobial activity against methicillin-resistant Staphylococcus aureus, extended-spectrum beta-lactamase-producing Escherichia coli, vancomycin-resistant Enterococcus faecalis and Candida albicans. Bioassay-guided isolation of the secondary metabolites of A. fumigatus led to the identification of gliotoxin.Conclusion:This study demonstrated proof of principle of using bioassay-guided isolation for finding bioactive molecules
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| 3. |
- Stedt, Johan, et al.
(författare)
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Antibiotic resistance patterns in Escherichia coli from gulls in nine European countries
- 2014
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Ingår i: Infection Ecology & Epidemiology. - : Informa UK Limited. - 2000-8686. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The prevalence of antibiotic resistant faecal indicator bacteria from humans and food production animals has increased over the last decades. In Europe, resistance levels in Escherichia coli from these sources show a south-to-north gradient, with more widespread resistance in the Mediterranean region compared to northern Europe. Recent studies show that resistance levels can be high also in wildlife, but it is unknown to what extent resistance levels in nature conform to the patterns observed in human-associated bacteria.METHODS: To test this, we collected 3,158 faecal samples from breeding gulls (Larus sp.) from nine European countries and tested 2,210 randomly isolated E. coli for resistance against 10 antibiotics commonly used in human and veterinary medicine.RESULTS: Overall, 31.5% of the gull E. coli isolates were resistant to ≥1 antibiotic, but with considerable variation between countries: highest levels of isolates resistant to ≥1 antibiotic were observed in Spain (61.2%) and lowest levels in Denmark (8.3%). For each tested antibiotic, the Iberian countries were either the countries with the highest levels or in the upper range in between-country comparisons, while northern countries generally had a lower proportion of resistant E. coli isolates, thereby resembling the gradient of resistance seen in human and food animal sources.CONCLUSION: We propose that gulls may serve as a sentinel of environmental levels of antibiotic resistant E. coli to complement studies of human-associated microbiota.
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| 4. |
- Blomqvist, Maria, et al.
(författare)
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Chlamydophila psittaci in birds of prey, Sweden
- 2012
-
Ingår i: Infection Ecology & Epidemiology. - : Informa UK Limited. - 2000-8686. ; 2
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Chlamydia psittaci is an intracellular bacterium primarily causing respiratory diseases in birds but may also be transmitted to other animals, including humans. The prevalence of the pathogen in wild birds in Sweden is largely unknown.Methods: DNA was extracted from cloacae swabs and screened for C. psittaci by using a 23S rRNA gene PCR assay. Partial 16S rRNA and ompA gene fragments were sequence determined and phylogenies were analysed by the neighbour-joining method.Results and conclusion: The C. psittaci prevalence was 1.3% in 319 Peregrine Falcons and White-tailed Sea Eagles, vulnerable top-predators in Sweden. 16S rRNA and ompA gene analysis showed that novel Chlamydia species, as well as novel C. psittaci strains, are to be found among wild birds.
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| 5. |
- Hagman, Karl, et al.
(författare)
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On the potential roles of ticks and migrating birds in the ecology of West Nile virus
- 2014
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Ingår i: Infection Ecology & Epidemiology. - : Informa UK Limited. - 2000-8686. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Mosquitoes are the primary vectors of West Nile virus (WNV). Ticks have, however, been suggested to be potential reservoirs of WNV. In order to investigate their role in the spread of the virus, ticks, which had been collected from birds migrating northwards from Africa to Europe, were analyzed for the potential presence of WNV-RNA.METHODS: On the Mediterranean islands Capri and Antikythira a total of 14,824 birds were captured and investigated from which 747 ticks were collected.RESULTS AND CONCLUSION: Most of the identified ticks (93%) were nymphs and larvae of Hyalomma marginatum sensu lato, most of which were or appear to be Hyalomma rufipes. Of these ticks 729 were individually screened for WNV-RNA. None of the ticks was found to be WNV positive. Thus, there was no evidence that Hyalomma marginatum s.l. ticks play a role in the spread of WNV from Africa to Europe.
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| 6. |
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| 7. |
- Ottoson, Jakob, et al.
(författare)
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A longitudinal study of antimicrobial resistant faecal bacteria in sediments collected from a hospital wastewater system
- 2012
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Ingår i: Infection Ecology & Epidemiology. - : Informa UK Limited. - 2000-8686. ; 2, s. 7438-
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Tidskriftsartikel (refereegranskat)abstract
- Objective:The objective with this study was to determine and follow antimicrobial resistance in faecal bacteria over time in hospital wastewater pipe sediment. A further aim was to determine bacterial growth rates of sensitive, intermediate and resistant intestinal enterococci in different ciprofloxacin concentrations as a measure of bacterial fitness.Methods:A system enabling the collection of settled particles over time was installed at Kalmar County Hospital. Samples were collected bi-monthly for a 14-month period. Coliform bacteria and enterococci were isolated from the sediment with standard methods and investigated for resistance to ciprofloxacin (CIP), imipenem (IMI), trimetroprim-sulfamethoxazole (TS), ampicillin (AMP) and vancomycin (VAN) by the disc diffusion method. Resistant isolates were further typed with the PhenePlateTM system. Growth assessments were performed with an automated spectrophotometer.Results:The rate of intestinal enterococci resistance was < 0.6, 1.3, 1.9 and 13% to VAN, IMI, AMP and CIP respectively. Coliform resistance frequencies were 1.1, 2.2 and 2.2% to CIP, IMI and TS respectively. At two sampling occasions, significantly higher rates of ciprofloxacin resistant enterococci were found and the establishment of a resistant clone in the sewer was indicated by the PhP-analysis. Ciprofloxacin resistant intestinal enterococci had a significantly longer lag-phase time than sensitive isolates, but from 500 µg ml-1 (half MIC) resistant isolates had a competitive advantage in terms of significantly faster generation time.Discussion:Despite high concentration of antimicrobials in the sediment, resistance frequencies were generally low. This can depend on limited growth possibilities for faecal bacteria. However, the establishment of a resistant clone shows that hospital sewers can serve as a reservoir for antibiotic resistant bacteria.
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