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  • 1. Ahlm, Clas
    et al.
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Koskinen, Lars-Owe D
    Monsen, Tor
    Brain abscess caused by methicillin resistant Staphylococcus aureus (MRSA)2000In: Scandinavian Journal of Infectious Diseases, Vol. 32, p. 562-563Article in journal (Refereed)
  • 2.
    Ahlstrom, Christina A.
    et al.
    US Geol Survey, Alaska Sci Ctr, Anchorage, AK 99508 USA.
    Bonnedahl, Jonas
    Linkoping Univ, Dept Clin & Expt Med, SE-58183 Linkoping, Sweden;Kalmar Cty Hosp, Dept Infect Dis, SE-39185 Kalmar, Sweden.
    Woksepp, Hanna
    Kalmar Cty Hosp, Dept Clin Microbiol, SE-39185 Kalmar, Sweden.
    Hernandez, Jorge
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Ramey, Andrew M.
    US Geol Survey, Alaska Sci Ctr, Anchorage, AK 99508 USA.
    Acquisition and dissemination of cephalosporin-resistant E.coli in migratory birds sampled at an Alaska landfill as inferred through genomic analysis2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 7361Article in journal (Refereed)
    Abstract [en]

    Antimicrobial resistance (AMR) in bacterial pathogens threatens global health, though the spread of AMR bacteria and AMR genes between humans, animals, and the environment is still largely unknown. Here, we investigated the role of wild birds in the epidemiology of AMR Escherichia coli. Using next-generation sequencing, we characterized cephalosporin-resistant E. coli cultured from sympatric gulls and bald eagles inhabiting a landfill habitat in Alaska to identify genetic determinants conferring AMR, explore potential transmission pathways of AMR bacteria and genes at this site, and investigate how their genetic diversity compares to isolates reported in other taxa. We found genetically diverse E. coli isolates with sequence types previously associated with human infections and resistance genes of clinical importance, including blaCTX-M and blaCMY. Identical resistance profiles were observed in genetically unrelated E. coli isolates from both gulls and bald eagles. Conversely, isolates with indistinguishable core-genomes were found to have different resistance profiles. Our findings support complex epidemiological interactions including bacterial strain sharing between gulls and bald eagles and horizontal gene transfer among E. coli harboured by birds. Results suggest that landfills may serve as a source for AMR acquisition and/or maintenance, including bacterial sequence types and AMR genes relevant to human health.

  • 3.
    Ahlstrom, Christina A.
    et al.
    US Geol Survey, Alaska Sci Ctr, Anchorage, AK 99508 USA.
    Bonnedahl, Jonas
    Linkoping Univ, Dept Clin & Expt Med, Linkoping, Sweden;Kalmar Cty Council, Dept Infect Dis, Kalmar, Sweden.
    Woksepp, Hanna
    Kalmar Cty Hosp, Res Sect, Dept Dev & Publ Hlth, Kalmar, Sweden.
    Hernandez, Jorge
    Kalmar Cty Hosp, Dept Clin Microbiol, Kalmar, Sweden.
    Reed, John A.
    US Geol Survey, Alaska Sci Ctr, Anchorage, AK 99508 USA.
    Tibbitts, Lee
    US Geol Survey, Alaska Sci Ctr, Anchorage, AK 99508 USA.
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine.
    Douglas, David C.
    US Geol Survey, Alaska Sci Ctr, Juneau, AK USA.
    Ramey, Andrew M.
    US Geol Survey, Alaska Sci Ctr, Anchorage, AK 99508 USA.
    Satellite tracking of gulls and genomic characterization of faecal bacteria reveals environmentally mediated acquisition and dispersal of antimicrobial-resistant Escherichia coli on the Kenai Peninsula, Alaska2019In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 28, no 10, p. 2531-2545Article in journal (Refereed)
    Abstract [en]

    Gulls (Larus spp.) have frequently been reported to carry Escherichia coli exhibiting antimicrobial resistance (AMR E. coli); however, the pathways governing the acquisition and dispersal of such bacteria are not well described. We equipped 17 landfill-foraging gulls with satellite transmitters and collected gull faecal samples longitudinally from four locations on the Kenai Peninsula, Alaska to assess: (a) gull attendance and transitions between sites, (b) spatiotemporal prevalence of faecally shed AMR E. coli, and (c) genomic relatedness of AMR E. coli isolates among sites. We also sampled Pacific salmon (Oncorhynchus spp.) harvested as part of personal-use dipnet fisheries at two sites to assess potential contamination with AMR E. coli. Among our study sites, marked gulls most commonly occupied the lower Kenai River (61% of site locations) followed by the Soldotna landfill (11%), lower Kasilof River (5%) and upper Kenai River (<1%). Gulls primarily moved between the Soldotna landfill and the lower Kenai River (94% of transitions among sites), which were also the two locations with the highest prevalence of AMR E. coli. There was relatively high spatial and temporal variability in AMR E. coli prevalence in gull faeces and there was no evidence of contamination on salmon harvested in personal-use fisheries. We identified E. coli sequence types and AMR genes of clinical importance, with some isolates possessing genes associated with resistance to as many as eight antibiotic classes. Our findings suggest that gulls acquire AMR E. coli at habitats with anthropogenic inputs and subsequent movements may represent pathways through which AMR is dispersed.

  • 4.
    Antonodimitrakis, Pantelis
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Tumor Biology.
    Wassberg, Cecilia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET.
    Gerovasileiou, Spyridon
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Back, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Rheumatology.
    Hallgren, Roger
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Fulminant hemophagocytic lymphohistiocytosis secondary to a reactivated EBV infection: A case report2013In: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 118, no 1, p. 42-45Article in journal (Refereed)
    Abstract [en]

    Hemophagocytic lymphohistiocytosis (HLH) is an aggressive inflammatory syndrome that results from inappropriate activation of the immune system. HLH has a high mortality if not treated. We describe a case of a fulminant HLH, associated with a reactivation of an EBV infection. The patient responded well to steroid treatment.

  • 5. Ardiles-Villegas, Karen
    et al.
    Gonzalez-Acuna, Daniel
    Waldenstrom, Jonas
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Hernandez, Jorge
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Antibiotic Resistance Patterns in Fecal Bacteria Isolated from Christmas Shearwater (Puffinus nativitatis) and Masked Booby (Sula dactylatra) at Remote Easter Island2011In: Avian diseases, ISSN 0005-2086, E-ISSN 1938-4351, Vol. 55, no 3, p. 486-489Article in journal (Refereed)
    Abstract [en]

    Antibiotic use and its implications have been discussed extensively in the past decades. This situation has global consequences when antibiotic resistance becomes widespread in the intestinal bacterial flora of stationary and migratory birds. This study investigated the incidence of fecal bacteria and general antibiotic resistance, with special focus on extended spectrum beta-lactamase (ESBL) isolates, in two species of seabirds at remote Easter Island. We identified 11 species of bacteria from masked booby (Sula dactylatra) and Christmas shearwater (Puffinus nativitatis); five species of gram-negative bacilli, four species of Streptococcus (Enterococcus), and 2 species of Staphylococcus. In addition, 6 types of bacteria were determined barely to the genus level. General antibiotic susceptibility was measured in the 30 isolated Enterobacteriaceae to 11 antibiotics used in human and veterinary medicine. The 10 isolates that showed a phenotypic ESBL profile were verified by clavulanic acid inhibition in double mixture discs with cefpodoxime, and two ESBL strains were found, one strain in masked booby and one strain in Christmas shearwater. The two bacteria harboring the ESBL type were identified as Serratia odorifera biotype 1, which has zoonotic importance. Despite minimal human presence in the masked booby and Christmas shearwater habitats, and the extreme geographic isolation of Easter Island, we found several multiresistant bacteria and even two isolates with ESBL phenotypes. The finding of ESBLs has animal and public health significance and is of potential concern, especially because the investigation was limited in size and indicated that antibiotic-resistant bacteria now are distributed globally.

  • 6.
    Ardiles-Villegas, Karen
    et al.
    Universidad de Concepción, Chile.
    González-Acuña, Daniel
    Universidad de Concepción, Chile.
    Waldenström, Jonas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Olsen, Björn
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Uppsala University.
    Hernandez, Jorge
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Uppsala University.
    Antibiotic resistance patterns in fecal bacteria isolated from Christmas shearwater (Puffinus nativitatis) and masked booby (Sula dactylatra) at remote Easter Island2011In: Avian diseases, ISSN 0005-2086, E-ISSN 1938-4351, Vol. 55, no 3, p. 486-489Article in journal (Refereed)
    Abstract [en]

    Antibiotic use and its implications have been discussed extensively in the past decades. This situation has global consequences when antibiotic resistance becomes widespread in the intestinal bacterial flora of stationary and migratory birds. This study investigated the incidence of fecal bacteria and general antibiotic resistance, with special focus on extended spectrum beta-lactamase (ESBL) isolates, in two species of seabirds at remote Easter Island. We identified 11 species of bacteria from masked booby (Sula dactylatra) and Christmas shearwater (Puffinus nativitatis); five species of gram-negative bacilli, four species of Streptococcus (Enterococcus), and 2 species of Staphylococcus. In addition, 6 types of bacteria were determined barely to the genus level. General antibiotic susceptibility was measured in the 30 isolated Enterobacteriaceae to 11 antibiotics used in human and veterinary medicine. The 10 isolates that showed a phenotypic ESBL profile were verified by clavulanic acid inhibition in double mixture discs with cefpodoxime, and two ESBL strains were found, one strain in masked booby and one strain in Christmas shearwater. The two bacteria harboring the ESBL type were identified as Serratia odorifera biotype 1, which has zoonotic importance. Despite minimal human presence in the masked booby and Christmas shearwater habitats, and the extreme geographic isolation of Easter Island, we found several multiresistant bacteria and even two isolates with ESBL phenotypes. The finding of ESBLs has animal and public health significance and is of potential concern, especially because the investigation was limited in size and indicated that antibiotic-resistant bacteria now are distributed globally.

  • 7. Artursson, Karin
    et al.
    Järhult, Josef D
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Berg, Charlotte
    Varför är det så svårt att förstå betydelsen av One Health?2014In: Svensk veterinärtidning, ISSN 0346-2250, Vol. Feb, no 2, p. 35-39Article in journal (Refereed)
  • 8.
    Atterby, Clara
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine.
    Mourkas, Evangelos
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. Univ Bath, Dept Biol & Biochem, Milner Ctr Evolut, Bath, Avon, England.
    Meric, Guillaume
    Univ Bath, Dept Biol & Biochem, Milner Ctr Evolut, Bath, Avon, England.
    Pascoe, Ben
    Univ Bath, Dept Biol & Biochem, Milner Ctr Evolut, Bath, Avon, England;MRC CLIMB Consortium, Bath, Avon, England.
    Wang, Helen
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Waldenström, Jonas
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, Kalmar, Sweden.
    Sheppard, Samuel K.
    Univ Bath, Dept Biol & Biochem, Milner Ctr Evolut, Bath, Avon, England;MRC CLIMB Consortium, Bath, Avon, England.
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine.
    Järhult, Josef D.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine.
    Ellström, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine.
    The Potential of Isolation Source to Predict Colonization in Avian Hosts: A Case Study in Campylobacter jejuni Strains From Three Bird Species2018In: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 9, article id 591Article in journal (Refereed)
    Abstract [en]

    Campylobacter jejuni is the primary cause of bacterial gastroenteritis worldwide, infecting humans mostly through consumption of contaminated poultry. C. jejuni is common in the gut of wild birds, and shows distinct strain-specific association to particular bird species. This contrasts with farm animals, in which several genotypes co-exist. It is unclear if the barriers restricting transmission between host species of such specialist strains are related to environmental factors such as contact between host species, bacterial survival in the environment, etc., or rather to strain specific adaptation to the intestinal environment of specific hosts. We compared colonization dynamics in vivo between two host-specific C. jejuni from a song thrush (ST-1304 complex) and a mallard (ST-995), and a generalist strain from chicken (ST-21 complex) in a wild host, the mallard (Anas platyrhynchos). In 18-days infection experiments, the song thrush strain showed only weak colonization and was cleared from all birds after 10 days, whereas both mallard and chicken strains remained stable. When the chicken strain was given 4 days prior to co-infection of the same birds with a mallard strain, it was rapidly outcompeted by the latter. In contrast, when the mallard strain was given 4 days prior to co-infection with the chicken strain, the mallard strain remained and expansion of the chicken strain was delayed. Our results suggest strain-specific differences in the ability of C. jejuni to colonize mallards, likely associated with host origin. This difference might explain observed host association patterns in C. jejuni from wild birds.

  • 9.
    Axelsson Olsson, Diana
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Ellström, Patrik
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Haemig, Paul D
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Brudin, Lars
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Acanthamoeba-Campylobacter coculture as a novel method for enrichment of Campylobacter species2007In: Applied and Environmental Microbiology, Vol. 73, no 21, p. 6864-6869Article in journal (Refereed)
    Abstract [en]

    In this study, we present a novel method to isolate and enrich low concentrations of Campylobacter pathogens. This method, Acanthamoeba-Campylobacter coculture (ACC), is based on the intracellular survival and multiplication of Campylobacter species in the free-living protozoan Acanthamoeba polyphaga. Four of the Campylobacter species relevant to humans and livestock, Campylobacter jejuni, C. coli, C. lari, and C. hyointestinalis, were effectively enriched by the coculture method, with growth rates comparable to those observed in other Campylobacter enrichment media. Studying six strains of C. jejuni isolated from different sources, we found that all of the strains could be enriched from an inoculum of fewer than 10 bacteria. The sensitivity of the ACC method was not negatively affected by the use of Campylobacter-selective antibiotics in the culture medium, but these were effective in suppressing the growth of seven different bacterial species added at a concentration of 10(4) CFU/ml of each species as deliberate contamination. The ACC method has advantages over other enrichment methods as it is not dependent on a microaerobic milieu and does not require the use of blood or other oxygen-quenching agents. Our study found the ACC method to be a promising tool for the enrichment of Campylobacter species, particularly from water samples with low bacterial concentrations.

  • 10.
    Axelsson Olsson, Diana
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Olofsson, Jenny
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Ellström, Patrik
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    A simple method for long-term storage Acanthamoeba species2009In: Parasitology Research, ISSN 0932-0113, E-ISSN 1432-1955, Vol. 104, no 4, p. 935-937Article in journal (Refereed)
    Abstract [en]

    We present a novel and simple technique for storing live Acanthamoeba for long periods of time. The amoebae are maintained at refrigerator temperatures in a peptone-yeast extract-glucose (PYG) medium normally used for cultivation. Using this method, we obtained survival rates of at least 4 years for Acanthamoeba polyphaga and 3 years for Acanthamoeba castellanii and Acanthamoeba rhysodes. Advantages of this storage method are: (1) it is quick and simple, (2) inexpensive, (3) does not require encystment before storage, (4) resuscitation of cysts can be achieved within a week of culture in PYG medium at 27A degrees C, and does not require co-culture with bacteria or any special equipment.

  • 11.
    Axelsson Olsson, Diana
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Olofsson, Jenny
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Svensson, Lovisa
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Griekspoor, Petra
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Waldenström, Jonas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Ellström, Patrik
    Clinical Bacteriology, Department of Medical Sciences, Uppsala University and Uppsala University Hospital, SE-751 85 Uppsala, Sweden.
    Olsen, Björn
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Amoebae and algae can prolong the survival of Campylobacter species in co-culture2010In: Experimental parasitology, ISSN 0014-4894, E-ISSN 1090-2449, Vol. 126, p. 59-64Article in journal (Refereed)
    Abstract [en]

    Several species of free-living amoebae can cause disease in humans. However, in addition to the direct pathogenicity of e.g. Acanthamoebae and Naegleria species, they are recognized as environmental hosts, indirectly involved in the epidemiology of many pathogenic bacteria. Although several studies have demonstrated intracellular survival of many different bacteria in these species, the extent of such interactions as well as the implications for the epidemiology of the bacterial species involved, are largely unknown and probably underestimated. In this study, we evaluated eight different unicellular eukaryotic organisms, for their potential to serve as environmental hosts for Campylobacter species. These organisms include four amoebozoas (Acanthamoeba polyphaga, Acanthamoeba castellanii, Acanthamoeba rhysodes and Hartmanella vermiformis), one alveolate (Tetrahymena pyriformis), one stramenopile (Dinobryon sertularia), one eugoenozoa (Euglena gracilis) and one heterolobosea (Naegleria americana). Campylobacter spp. including Campylobacter jejuni, Campylobacter coli and Campylobacter lari are the most common cause of gastroenteritis in the western world. Survival and replication of these three species as well as Campylobacter hyointestinalis were assessed in co-cultures with the eukaryotic organisms. Campylobacter spp. generally survived longer in co-cultures, compared to when incubated in the corresponding growth media. The eukaryotic species that best promoted bacterial survival was the golden algae D. sertularia. Three species of amoebozoas, of the genus Acanthamoeba promoted both prolonged survival and replication of Campylobacter spp. The high abundance in lakes, ponds and water distribution networks of these organisms indicate that they might have a role in the epidemiology of campylobacteriosis, possibly contributing to survival and dissemination of these intestinal pathogens to humans and other animals. The results suggest that not only C. jejuni, but a variety of Campylobacter spp. can interact with different eukaryotic unicellular organisms.

  • 12.
    Axelsson Olsson, Diana
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Svensson, Lovisa
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Olofsson, Jenny
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Salomon, Paulo
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Waldenström, Jonas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Ellström, Patrik
    Olsen, Björn
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Increase in Acid Tolerance of Campylobacter jejuni through Coincubation with Amoebae2010In: Applied and Environmental Microbiology, ISSN 0099-2240, E-ISSN 1098-5336, Vol. 76, no 13, p. 4194-4200Article in journal (Refereed)
    Abstract [en]

    Campylobacter jejuni is a recognized and common gastrointestinal pathogen in most parts of the world. Human infections are often food borne, and the bacterium is frequent among poultry and other food animals. However, much less is known about the epidemiology of C. jejuni in the environment and what mechanisms the bacterium depends on to tolerate low pH. The sensitive nature of C. jejuni stands in contrast to the fact that it is difficult to eradicate from poultry production, and even more contradictory is the fact that the bacterium is able to survive the acidic passage through the human stomach. Here we expand the knowledge on C. jejuni acid tolerance by looking at protozoa as a potential epidemiological pathway of infection. Our results showed that when C. jejuni cells were coincubated with Acanthamoeba polyphaga in acidified phosphate-buffered saline (PBS) or tap water, the bacteria could tolerate pHs far below those in their normal range, even surviving at pH 4 for 20 h and at pH 2 for 5 h. Interestingly, moderately acidic conditions (pH 4 and 5) were shown to trigger C. jejuni motility as well as to increase adhesion/internalization of bacteria into A. polyphaga. Taken together, the results suggest that protozoa may act as protective hosts against harsh conditions and might be a potential risk factor for C. jejuni infections. These findings may be important for our understanding of C. jejuni passage through the gastrointestinal tract and for hygiene practices used in poultry settings.

  • 13.
    Axelsson Olsson, Diana
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Broman, Tina
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Holmberg, M
    The protozoan Acanthamoeba polyphaga as a potential reservoir for Campylobacter jejuni2005In: Applied and environmental microbiology, Vol. 71 (2), p. 987-992Article in journal (Refereed)
  • 14. Axelsson-Olsson, Diana
    et al.
    Ellström, Patrik
    Waldenström, Jonas
    Haemig, Paul D.
    Brudin, Lars
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Acanthamoeba-Campylobacter coculture as a novel method for enrichment of Campylobacter species2007In: Applied and Environmental Microbiology, ISSN 0099-2240, E-ISSN 1098-5336, Vol. 73, no 21, p. 6864-6869Article in journal (Refereed)
    Abstract [en]

    In this study, we present a novel method to isolate and enrich low concentrations of Campylobacter pathogens. This method, Acanthamoeba-Campylobacter coculture (ACC), is based on the intracellular survival and multiplication of Campylobacter species in the free-living protozoan Acanthamoeba polyphaga. Four of the Campylobacter species relevant to humans and livestock, Campylobacter jejuni, C. coli, C. lari, and C. hyointestinalis, were effectively enriched by the coculture method, with growth rates comparable to those observed in other Campylobacter enrichment media. Studying six strains of C. jejuni isolated from different sources, we found that all of the strains could be enriched from an inoculum of fewer than 10 bacteria. The sensitivity of the ACC method was not negatively affected by the use of Campylobacter-selective antibiotics in the culture medium, but these were effective in suppressing the growth of seven different bacterial species added at a concentration of 10(4) CFU/ml of each species as deliberate contamination. The ACC method has advantages over other enrichment methods as it is not dependent on a microaerobic milieu and does not require the use of blood or other oxygen-quenching agents. Our study found the ACC method to be a promising tool for the enrichment of Campylobacter species, particularly from water samples with low bacterial concentrations.

  • 15. Bengtsson, Daniel
    et al.
    Avril, Alexis
    Gunnarsson, Gunnar
    Elmberg, Johan
    Soderquist, Par
    Norevik, Gabriel
    Tolf, Conny
    Safi, Kamran
    Fiedler, Wolfgang
    Wikelski, Martin
    Olsén, Bjorn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine.
    Waldenström, Jonas
    Movements, Home-Range Size and Habitat Selection of Mallards during Autumn Migration2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 6, p. e100764-Article in journal (Refereed)
    Abstract [en]

    The mallard (Anas platyrhynchos) is a focal species in game management, epidemiology and ornithology, but comparably little research has focused on the ecology of the migration seasons. We studied habitat use, time-budgets, home-range sizes, habitat selection, and movements based on spatial data collected with GPS devices attached to wild mallards trapped at an autumn stopover site in the Northwest European flyway. Sixteen individuals (13 males, 3 females) were followed for 15-38 days in October to December 2010. Forty-nine percent (SD = 8.4%) of the ducks' total time, and 85% of the day-time (SD = 28.3%), was spent at sheltered reefs and bays on the coast. Two ducks used ponds, rather than coast, as day-roosts instead. Mallards spent most of the night (76% of total time, SD = 15.8%) on wetlands, mainly on alvar steppe, or in various flooded areas (e.g. coastal meadows). Crop fields with maize were also selectively utilized. Movements between roosting and foraging areas mainly took place at dawn and dusk, and the home-ranges observed in our study are among the largest ever documented for mallards (mean = 6,859 ha; SD = 5,872 ha). This study provides insights into relatively unknown aspects of mallard ecology. The fact that autumn-staging migratory mallards have a well-developed diel activity pattern tightly linked to the use of specific habitats has implications for wetland management, hunting and conservation, as well as for the epidemiology of diseases shared between wildlife and domestic animals.

  • 16.
    Bengtsson, Daniel
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Avril, Alexis
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Gunnarsson, Gunnar
    Kristianstad University.
    Elmberg, Johan
    Kristianstad University.
    Söderquist, Pär
    Kristianstad University.
    Norevik, Gabriel
    Ottenby Bird Observatory.
    Tolf, Conny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Safi, Kamran
    Max Planck Institute for Ornitholology, Germany ; University of Konstanz, Germany.
    Fiedler, Wolfgang
    Max Planck Institute for Ornitholology, Germany ; University of Konstanz, Germany.
    Wikelski, Martin
    Max Planck Institute for Ornitholology, Germany ; University of Konstanz, Germany.
    Olsen, Björn
    Uppsala University.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Movements, Home-Range Size and Habitat Selection of Mallards during Autumn Migration2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 6, article id e100764Article in journal (Refereed)
    Abstract [en]

    The mallard (Anas platyrhynchos) is a focal species in game management, epidemiology and ornithology, but comparably little research has focused on the ecology of the migration seasons. We studied habitat use, time-budgets, home-range sizes, habitat selection, and movements based on spatial data collected with GPS devices attached to wild mallards trapped at an autumn stopover site in the Northwest European flyway. Sixteen individuals (13 males, 3 females) were followed for 15-38 days in October to December 2010. Forty-nine percent (SD = 8.4%) of the ducks' total time, and 85% of the day-time (SD = 28.3%), was spent at sheltered reefs and bays on the coast. Two ducks used ponds, rather than coast, as day-roosts instead. Mallards spent most of the night (76% of total time, SD = 15.8%) on wetlands, mainly on alvar steppe, or in various flooded areas (e.g. coastal meadows). Crop fields with maize were also selectively utilized. Movements between roosting and foraging areas mainly took place at dawn and dusk, and the home-ranges observed in our study are among the largest ever documented for mallards (mean = 6,859 ha; SD = 5,872 ha). This study provides insights into relatively unknown aspects of mallard ecology. The fact that autumn-staging migratory mallards have a well-developed diel activity pattern tightly linked to the use of specific habitats has implications for wetland management, hunting and conservation, as well as for the epidemiology of diseases shared between wildlife and domestic animals.

  • 17. Bengtsson, Daniel
    et al.
    Safi, Kamran
    Avril, Alexis
    Fiedler, Wolfgang
    Wikelski, Martin
    Gunnarsson, Gunnar
    Elmberg, Johan
    Tolf, Conny
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Waldenström, Jonas
    Does influenza A virus infection affect movement behaviour during stopover in its wild reservoir host?2016In: The Royal Society, ISSN 2054-5703, Vol. 3, no 2, article id UNSP 150633Article in journal (Refereed)
    Abstract [en]

    The last decade has seen a surge in research on avian influenza A viruses (IAVs), in part fuelled by the emergence, spread and potential zoonotic importance of highly pathogenic virus subtypes. The mallard (Anas platyrhynchos) is the most numerous and widespread dabbling duck in the world, and one of the most important natural hosts for studying IAV transmission dynamics. In order to predict the likelihood of IAV transmission between individual ducks and to other hosts, as well as between geographical regions, it is important to understand how IAV infection affects the host. In this study, we analysed the movements of 40 mallards equipped with GPS transmitters and three-dimensional accelerometers, of which 20 were naturally infected with low pathogenic avian influenza virus (LPAIV), at a major stopover site in the Northwest European flyway. Movements differed substantially between day and night, as well as between mallards returning to the capture site and those feeding in natural habitats. However, movement patterns did not differ between LPAIV infected and uninfected birds. Hence, LPAIV infection probably does not affect mallard movements during stopover, with high possibility of virus spread along the migration route as a consequence.

  • 18. Bergström, Sven
    et al.
    Haemig, Paul D
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Distribution and abundance of the tick Ixodes uriae in a subantarctic seabird community1999In: Journal of Parasitology, Vol. 85, p. 25-27Article in journal (Refereed)
  • 19. Bergström, Sven
    et al.
    Haemig, Paul D
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Increased mortality of black-browed albatross chicks at a colony heavily-infested with the tick Ixodes uriae1999In: International Journal for Parasitology, Vol. 29, p. 1359-1361Article in journal (Refereed)
  • 20. Bergström, Sven
    et al.
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Burman, N
    Gothefors, L
    Jaenson, Thomas G T
    Jonsson, M
    Mejlon, H
    Molecular characterization of Borrelia burgdorferi isolated from Ixodes ricinus in northern Sweden1992In: Scandinavian journal of infectious diseases, Vol. 24, p. 181-188Article in journal (Refereed)
  • 21. Bjöersdorff, Anneli
    et al.
    Bergström, Sven
    Massung, Robert F
    Haemig, Paul D
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Ehrlichia-infected ticks on migrating birds2001In: Emerging Infectious Diseases, Vol. 7, p. 877-879Article in journal (Refereed)
  • 22.
    Blomqvist, Maria
    et al.
    Uppsala University.
    Christerson, Linus
    Uppsala University.
    Waldenström, Jonas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Herrmann, Björn
    Uppsala University.
    Olsen, Björn
    Uppsala Univ, Dept Med Sci, Sect Infect Dis, S-75185 Uppsala, Sweden.
    Chlamydia psittaci in Swedish Wetland Birds: A Risk to Zoonotic Infection?2012In: Avian diseases, ISSN 0005-2086, E-ISSN 1938-4351, Vol. 56, no 4, p. 737-740Article in journal (Refereed)
    Abstract [en]

    Chlamydia psittaci in birds may be transmitted to humans and cause respiratory infections, sometimes as severe disease. Our study investigated the C. psittaci prevalence in migratory birds in Sweden by real-time PCR. Fecal specimens or cloacal swabs were collected from 497 birds from 22 different species, mainly mallards (Anas platyrhynchos), at two bird observatories in Sweden. DNA from C. psittaci was found in six (1.2%) birds from three different species. Five of the positive specimens were infected with four novel strains of C. psittaci, based on sequencing of partial 16S rRNA gene and ompA gene, and the sixth was indentified as a recently described Chlamydiaceae-like bacterium. Considering exposure to humans it is concluded that the risk of zoonotic infection is low.

  • 23.
    Blomqvist, Maria
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Christerson, Linus
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Waldenström, Jonas
    Herrmann, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Chlamydia psittaciin Swedish Wetland Birds: A Risk to Zoonotic Infection2012In: Avian diseases, ISSN 0005-2086, E-ISSN 1938-4351, Vol. 56, no 4, p. 737-740Article in journal (Refereed)
    Abstract [en]

    Chlamydia psittaci in birds may be transmitted to humans and cause respiratory infections, sometimes as severe disease. Our study investigated the C. psittaci prevalence in migratory birds in Sweden by real-time PCR. Fecal specimens or cloacal swabs were collected from 497 birds from 22 different species, mainly mallards (Anas platyrhynchos), at two bird observatories in Sweden. DNA from C. psittaci was found in six (1.2%) birds from three different species. Five of the positive specimens were infected with four novel strains of C. psittaci, based on sequencing of partial 16S rRNA gene and ompA gene, and the sixth was indentified as a recently described Chlamydiaceae-like bacterium. Considering exposure to humans it is concluded that the risk of zoonotic infection is low.

  • 24.
    Blomqvist, Maria
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology.
    Christerson, Linus
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology.
    Waldenström, Jonas
    Lindberg, Peter
    Helander, Björn
    Gunnarsson, Gunnar
    Herrmann, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology.
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Chlamydia psittaci in birds of prey, Sweden2012In: Infection ecology & epidemiology, ISSN 2000-8686, Vol. 2, p. 8435-Article in journal (Refereed)
    Abstract [en]

    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.

  • 25. Bonnedahl, Jonas
    et al.
    Broman, Tina
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Palmgren, Helena
    Niskanen, Taina
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    In search of human-associated bacterial pathogens in Antarctic wildlife: report from six penguin colonies regularly visited by tourists2005In: Ambio, Vol. 34, p. 424-426Article in journal (Refereed)
  • 26.
    Bonnedahl, Jonas
    et al.
    Uppsala University ; Kalmar County Hospital.
    Drobni, M
    Gauthier-Clerc, M
    Hernandez, Jorge
    Kalmar County Hospital.
    Granholm, S
    Kayser, Y
    Melhus, Å
    Kahlmeter, G
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Johansson, A
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Dissemination of Escherichia coli with CTX-M Type ESBL between Humans and Yellow-Legged Gulls in the South of France2009In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 4, no Article number: e5958Article in journal (Refereed)
    Abstract [en]

     Extended Spectrum beta-Lactamase (ESBL) producing Enterobacteriaceae started to appear in the 1980s, and have since emerged as some of the most significant hospital-acquired infections with Escherichia coli and Klebsiella being main players. More than 100 different ESBL types have been described, the most widespread being the CTX-M beta-lactamase enzymes (bla(CTX-M) genes). This study focuses on the zoonotic dissemination of ESBL bacteria, mainly CTX-M type, in the southern coastal region of France. We found that the level of general antibiotic resistance in single randomly selected E. coli isolates from wild Yellow-legged Gulls in France was high. Nearly half the isolates (47,1%) carried resistance to one or more antibiotics (in a panel of six antibiotics), and resistance to tetracycline, ampicillin and streptomycin was most widespread. In an ESBL selective screen, 9,4% of the gulls carried ESBL producing bacteria and notably, 6% of the gulls carried bacteria harboring CTX-M-1 group of ESBL enzymes, a recently introduced and yet the most common clinical CTX-M group in France. Multi locus sequence type and phylogenetic group designations were established for the ESBL isolates, revealing that birds and humans share E. coli populations. Several ESBL producing E. coli isolated from birds were identical to or clustered with isolates with human origin. Hence, wild birds pick up E. coli of human origin, and with human resistance traits, and may accordingly also act as an environmental reservoir and melting pot of bacterial resistance with a potential to re-infect human populations.

  • 27.
    Bonnedahl, Jonas
    et al.
    Uppsala University ; Kalmar County Hospital.
    Drobni, P.
    Cent Hosp Växjö.
    Johansson, A.
    Umeå University.
    Hernandez, Jorge
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Uppsala University.
    Melhus, A.
    Uppsala University.
    Stedt, Johan
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Olsen, Björn
    Uppsala University.
    Drobni, M.
    Uppsala University.
    Characterization, and comparison, of human clinical and black-headed gull (Larus ridibundus) extended-spectrum beta-lactamase-producing bacterial isolates from Kalmar, on the southeast coast of Sweden2010In: Journal of Antimicrobial Chemotherapy, ISSN 0305-7453, E-ISSN 1460-2091, Vol. 65, no 9, p. 1939-1944Article in journal (Refereed)
    Abstract [en]

    Antibiotic resistance is one of the great challenges for modern healthcare. In Gram-negative bacteria, CTX-M-type extended-spectrum beta-lactamases (ESBLs) have been rapidly spreading through Europe since the early 2000s. In Sweden, ESBL-producing Escherichia coli are still rare, but a 3-fold increase has been seen from 2004 to 2007. Enterobacteria and normal flora of wild animals, with or without antibiotic resistance traits, constitute a potential source of human infection and colonization. We studied wild birds with the aim to understand the environmental dissemination of antibiotic resistance and, focusing on clinically relevant resistance types, we made comparisons with human clinical samples. In this study, ESBL-producing human clinical isolates and isolates from juvenile black-headed gulls from Kalmar County hospital and the city of Kalmar, respectively, on the southeast coast of Sweden, were characterized and compared. Despite a low frequency of antibiotic resistance among the isolates from gulls, ESBL-producing E. coli isolates were found, two with bla(CTX-M-14) and one with bla(CTX-M-15). The same CTX-M types were dominant among human ESBL isolates. In addition, gull isolates were dispersed among the human samples in the PhenePlate (TM) clustering system, indicating that they neither differ from the human isolates nor form any separate clonal clustering. The finding of CTX-M-type ESBLs in E. coli isolated from black-headed gulls in Sweden, where 'background resistance' is low, is consistent with an ongoing environmental spread of these plasmid-borne resistance genes. The results indicate that a potential for transfer between the human population and environment exists even in countries with a low level of antibiotic resistance.

  • 28. Bonnedahl, Jonas
    et al.
    Hernandez, Jorge
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine.
    Stedt, Johan
    Waldenstrom, Jonas
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Drobni, Mirva
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine.
    Extended-Spectrum beta-Lactamases in Escherichia coli and Klebsiella pneumoniae in Gulls, Alaska, USA2014In: Emerging Infectious Diseases, ISSN 1080-6040, E-ISSN 1080-6059, Vol. 20, no 5, p. 897-899Article in journal (Refereed)
  • 29. Bonnedahl, Jonas
    et al.
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Broman, Tina
    Jalava, J
    Huovinen, P
    Österblad, Monika
    Antibiotic susceptibility of faecal bacteria in Antarctic penguins2008In: Polar Biology, ISSN 0722-4060, E-ISSN 1432-2056, Vol. 31, p. 759-763Article in journal (Refereed)
  • 30.
    Bonnedahl, Jonas
    et al.
    Linnaeus Univ, Sch Nat Sci, Ctr Ecol & Evolut Microbial Model Syst, SE-39182 Kalmar, Sweden.;Kalmar Cty Hosp, Dept Infect Dis, SE-39185 Kalmar, Sweden..
    Stedt, Johan
    Linnaeus Univ, Sch Nat Sci, Ctr Ecol & Evolut Microbial Model Syst, SE-39182 Kalmar, Sweden..
    Waldenstrom, Jonas
    Linnaeus Univ, Sch Nat Sci, Ctr Ecol & Evolut Microbial Model Syst, SE-39182 Kalmar, Sweden..
    Svensson, Lovisa
    Linnaeus Univ, Sch Nat Sci, Ctr Ecol & Evolut Microbial Model Syst, SE-39182 Kalmar, Sweden..
    Drobni, Mirva
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine.
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Comparison of Extended-Spectrum beta-Lactamase (ESBL) CTX-M Genotypes in Franklin Gulls from Canada and Chile2015In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 10, article id e0141315Article in journal (Refereed)
    Abstract [en]

    Migratory birds have been suggested to contribute to long-distance dispersal of antimicrobial resistant bacteria, but tests of this hypothesis are lacking. In this study we determined resistance profiles and genotypes of ESBL-producing bacteria in randomly selected Escherichia coli from Franklin's gulls (Leucophaeus pipixcan) at breeding sites in Canada and compared with similar data from the gulls' wintering grounds in Chile. Resistant E. coli phenotypes were common, most notably to ampicillin (30.1%) and cefadroxil (15.1%). Furthermore, 17.0% of the gulls in Canada carried ESBL producing bacteria, which is higher than reported from human datasets from the same country. However, compared to gulls sampled in Chile (30.1%) the prevalence of ESBL was much lower. The dominant ESBL variants in Canada were bla(CTX-M-14) and bla(CTX-M-15) and differed in proportions to the data from Chile. We hypothesize that the observed differences in ESBL variants are more likely linked to recent exposure to bacteria from anthropogenic sources, suggesting high local dissemination of resistant bacteria both at breeding and non-breeding times rather than a significant trans-hemispheric exchange through migrating birds.

  • 31.
    Bonnedahl, Jonas
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Kalmar County Hospital.
    Stedt, Johan
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Svensson, Lovisa
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Drobni, Mirva
    Uppsala University.
    Olsen, Björn
    Uppsala University.
    Comparison of Extended-Spectrum beta-Lactamase (ESBL) CTX-M Genotypes in Franklin Gulls from Canada and Chile2015In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 10, article id e0141315Article in journal (Refereed)
    Abstract [en]

    Migratory birds have been suggested to contribute to long-distance dispersal of antimicrobial resistant bacteria, but tests of this hypothesis are lacking. In this study we determined resistance profiles and genotypes of ESBL-producing bacteria in randomly selected Escherichia coli from Franklin's gulls (Leucophaeus pipixcan) at breeding sites in Canada and compared with similar data from the gulls' wintering grounds in Chile. Resistant E. coli phenotypes were common, most notably to ampicillin (30.1%) and cefadroxil (15.1%). Furthermore, 17.0% of the gulls in Canada carried ESBL producing bacteria, which is higher than reported from human datasets from the same country. However, compared to gulls sampled in Chile (30.1%) the prevalence of ESBL was much lower. The dominant ESBL variants in Canada were bla(CTX-M-14) and bla(CTX-M-15) and differed in proportions to the data from Chile. We hypothesize that the observed differences in ESBL variants are more likely linked to recent exposure to bacteria from anthropogenic sources, suggesting high local dissemination of resistant bacteria both at breeding and non-breeding times rather than a significant trans-hemispheric exchange through migrating birds.

  • 32. Brojer, Caroline
    et al.
    Jarhult, Josef D.
    Muradrasoli, Shaman
    Soderstrom, Hanna
    Olsen, Björn
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Gavier-Widen, Dolores
    Pathobiology and virus shedding of low-pathogenic avian influenza virus (A/H1N1) infection in mallards exposed to oseltamivir2013In: Journal of Wildlife Diseases, ISSN 0090-3558, E-ISSN 1943-3700, Vol. 49, no 1, p. 103-113Article in journal (Refereed)
    Abstract [en]

    Low-pathogenic avian influenza (LPAI) viruses in wild birds are important as they can constitute the basis for the development of highly pathogenic avian influenza viruses or form part of human-adapted strains with pandemic potential. However, the pathogenesis of LPAI viruses is not well characterized in dabbling ducks, one of the natural reservoirs of LPAI viruses. Between 21 September 2009 and 21 December 2009, we used real-time reverse transcriptase polymerase chain reaction (q-PCR), histopathology, and immunohistochemistry (IHC) to study Mallards (Anas platyrhynchos) infected with an influenza A/H1N1 virus isolated from a wild Mallard in Sweden. The ducks were either inoculated intraesophageally ("artificial infection") or infected by virus shed by other ducks in the experiment ("contact infection"). The ducks were subjected to three low concentrations (80 ng/L, 1 mu g/L, and 80 mu g/L) of the active metabolite of oseltamivir (Tamiflu (R)), oseltamivir carboxylate (OC), which resulted in the development of the viral resistance mutation H274Y at 1 and 80 mu g/L. The LPAI virus infection was localized to the intestinal tract and cloacal bursa except in one Mallard. The exception was a duck euthanized 1 day postinoculation, whose infection was located solely in the lung, possibly due to intratracheal deposition of virus. The intestinal infection was characterized by occasional degenerating cells in the lamina propria and presence of viral antigen as detected by IHC, as well as positive q-PCR performed on samples from feces and intestinal contents. Histopathologic changes, IHC positivity, and viral shedding all indicated that the infection peaked early, around 2 days postinfection. Furthermore, more viral antigen and viral RNA were detected with IHC and q-PCR in the proximal parts early in the infection. There was no obvious difference in the course of the infection in artificial versus contact infection, when the level of OC was increased from 80 ng/L to 1 mu g/L (based on IHC and q-PCR), when the level of OC was increased to 80 mu/L, or when the resistance mutation H274Y developed (based on q-PCR).

  • 33. Broman, Tina
    et al.
    Bergström, Sven
    On, S L W
    Palmgren, Helena
    McCafferty, D J
    Sellin, Mats
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Isolation and characterization of Campylobacter jejuni subsp. jejuni from Macaroni penguins (Eudyptes chrysolophus) in the subantarctic region2000In: Applied and Environmental Microbiology, Vol. 66, p. 449-452Article in journal (Refereed)
  • 34. Broman, Tina
    et al.
    Palmgren, Helena
    Bergström, Sven
    Sellin, Mats
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Danielsson-Tham, Marie-Louise
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Campylobacter jejuni in Black-Headed Gulls (Larus ridibundus): prevalence, genotypes, and influence on C. jejuni epidemiology2002In: Journal of Clinical Microbiology, Vol. 40, p. 4594-4602Article in journal (Refereed)
  • 35. Broman, Tina
    et al.
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Dahlgren, Daniel
    Carlsson, Inger
    Eliasson, Ingvar
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Diversities and Similarities in PFGE profiles of Campylobacter jejuni isolated from Migrating Birds and Humans2004In: Journal of Applied Microbiology, Vol. 96, p. 834-843Article in journal (Refereed)
  • 36. Bröjer, Caroline
    et al.
    Järhult, Josef D.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Muradrasoli, Shaman
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Virology.
    Söderström, Hanna
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Gavier-Widén, Dolores
    Pathobiology and virus shedding of low-pathogenic avian influenza virus (A/H1N1) infection in mallards exposed to oseltamivir2013In: Journal of Wildlife Diseases, ISSN 0090-3558, E-ISSN 1943-3700, Vol. 49, no 1, p. 103-113Article in journal (Refereed)
    Abstract [en]

    Low-pathogenic avian influenza (LPAI) viruses in wild birds are important as they can constitute the basis for the development of high-pathogenic avian influenza (HPAI) viruses or form part of human-adapted strains with pandemic potential. However, the LPAI infection as such is not very well characterized in the natural reservoir, dabbling ducks, and results are in part contradictory. The effects on the infection by artificial versus natural infection, exposure to antiviral drugs or development of resistance have not been studied. Therefore, we used q-PCR, histopathology and immunohistochemistry (IHC) to study mallards infected with an influenza A/H1N1 virus isolated from a wild mallard in Sweden. The mallards were either inoculated intra-esophageally or infected by virus shed by other ducks in the experiment. The birds were subjected to low levels of the active metabolite of oseltamivir (Tamiflu®) and the resistance mutation H274Y developed during the course of the experiment.

    All mallards but one had a strictly intestinal localization of the LPAI infection. The exception was a bird euthanized one day post artificial inoculation whose infection was located solely in the lung, possibly due to intra-tracheal deposition of virus. The intestinal infection was characterized by degenerating cells in the lamina propria, infiltrating heterophils and lymphocytes as well as positivity of IHC and q-PCR on samples from feces and intestinal contents. Histopathological changes, IHC positivity and viral shedding all indicate that the infection peaked early, around two days post infection. Furthermore, the infection had a longitudinal progression in the intestine with more activity in the proximal parts early in the infection and vice versa as observed both by IHC and by q-PCR. There was no obvious difference in the course of the infection in artificial versus natural infection, when the level of OC was increased from 80 ng/L to 80 µg/L or when the resistance mutation H274Y developed.

  • 37. Bunikis, J
    et al.
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Fingerle, V
    Bonnedahl, Jonas
    Wilske, B
    Bergström, Sven
    Molecular polymorphism of the Lyme disease agent Borrelia garinii in northern Europe is influenced by a novel enzootic Borrelia focus in the North Atlantic1996In: Journal of Clinical Microbiology, Vol. 34, p. 364-368Article in journal (Refereed)
  • 38. Bunikis, J
    et al.
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Westman, G
    Bergström, Sven
    Variable serum immunoglobulin responses against different Borrelia burgdorferi sensu lato species in a population at risk for and patients with Lyme disease1995In: Journal of Clinical Microbiology, Vol. 33, p. 1473-1478Article in journal (Refereed)
  • 39. Christersson, Linus
    et al.
    Blomqvist, Maria
    Grannas, Karin
    Thollesson, Mikael
    Laroucau, Karine
    Waldenström, Jonas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Eliasson, Ingvar
    Olsen, Björn
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Herrmann, Björn
    A novel Chlamydiaceae-like bacterium found in fecal specimens from sea birds from the Bering Sea.2010In: Environmental Microbiology Reports, ISSN 1758-2229, E-ISSN 1758-2229, Vol. 2, no 4, p. 605-610Article in journal (Refereed)
    Abstract [en]

    The family Chlamydiaceae contains several bacterial pathogens of important human and veterinary medical concern, such as Chlamydia trachomatis and Chlamydophila psittaci. Within the order Chlamydiales there are also an increasing number of chlamydia-like bacteria whose biodiversity, host range and environmental spread seem to have been largely underestimated, and which are currently being investigated for their potential medical relevance. In this study we present 16S rRNA, rnpB and ompA gene sequence data congruently indicating a novel chlamydia-like bacterium found in faecal specimens from opportunistic fish-eating sea birds, belonging to the Laridae and Alcidae families, from the Bering Sea. This novel bacterium appears to be closer to the Chlamydiaceae than other chlamydia-like bacteria and is most likely a novel genus within the Chlamydiaceae family.

  • 40. Chryssanthou, E.
    et al.
    Wennberg, H.
    Bonnedahl, Jonas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Occurrence of yeasts in faecal samples from Antarctic and South American seabirds2011In: Mycoses (Berlin), ISSN 0933-7407, E-ISSN 1439-0507, Vol. 54, no 6, p. e811-e815Article in journal (Refereed)
    Abstract [en]

    During an expedition to the Southern Argentinean town of Ushuaia, the Antarctic Peninsula, Antarctic Islands and the Falkland Islands, we collected 94 faecal specimens from wild birds to screen for yeast within the different bird species. The yeast species were identified by morphological features and commercial characterisation kits. From 54% of the specimens, we isolated 122 strains representing 29 yeast species. Debaryomyces hansenii, Candida lambica and Candida krusei were the most frequently isolated species. We found a plethora of yeasts in birds living in proximity to humans, whereas birds living in more remote areas were colonised with a lower number of fungal species.

  • 41.
    Chryssanthou, E.
    et al.
    Karolinska Univ Hosp.
    Wennberg, H.
    Karolinska Univ Hosp.
    Bonnedahl, Jonas
    Kalmar County Hospital ; Uppsala University.
    Olsen, Björn
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Uppsala University.
    Occurrence of yeasts in faecal samples from Antarctic and South American seabirds2011In: Mycoses (Berlin), ISSN 0933-7407, E-ISSN 1439-0507, Vol. 54, no 6, p. E811-E815Article in journal (Refereed)
    Abstract [en]

    During an expedition to the Southern Argentinean town of Ushuaia, the Antarctic Peninsula, Antarctic Islands and the Falkland Islands, we collected 94 faecal specimens from wild birds to screen for yeast within the different bird species. The yeast species were identified by morphological features and commercial characterisation kits. From 54% of the specimens, we isolated 122 strains representing 29 yeast species. Debaryomyces hansenii, Candida lambica and Candida krusei were the most frequently isolated species. We found a plethora of yeasts in birds living in proximity to humans, whereas birds living in more remote areas were colonised with a lower number of fungal species.

  • 42. Comstedt, Pär
    et al.
    Bergström, Sven
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Garpmo, Ulf
    Marjavaara, L
    Mejlon, H
    Barbour, A G
    Bunikis, J
    Migratory passerine birds as reservoirs of lyme borreliosis in Europe2006In: Emerging infectious diseases, Vol. 12, no 7, p. 1087-1095Article in journal (Refereed)
  • 43. Comstedt, Pär
    et al.
    Bergström, Sven
    Olsen, Björn
    Garpmo, Ulf
    Marjavaara, Lisette
    Mejlon, Hans
    Uppsala University, Museums etc., Museum of Evolution.
    Barbour, Alan G.
    Bunikis, Jonas
    Migratory passerine birds as reservoirs of Lyme borreliosis in Europe2006In: Emerging Infect. Dis., Vol. 12, p. 1087-1095Article in journal (Refereed)
  • 44.
    Elfving, Karin
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology. Department of Clinical Microbiology, Falu Hospital, Falun, Sweden.
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Bergström, Sven
    Department of Molecular Biology, Umeå University.
    Waldenström, Jonas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Lundkvist, Åke
    Swedish Institute for Infectious Disease Control, Solna.
    Sjöstedt, Anders
    Clinical Bacteriology, Department of Clinical Mic0robiology, Umeå University Hospital.
    Mejlon, Hans
    Uppsala University, Music and Museums, Museum of Evolution.
    Nilsson, Kenneth
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Dissemination of Spotted Fever Rickettsia Agents in Europe by Migrating Birds2010In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 5, no 1, p. e8572-Article in journal (Refereed)
    Abstract [en]

    Migratory birds are known to play a role as long-distance vectors for many microorganisms. To investigate whether this is true of rickettsial agents as well, we characterized tick infestation and gathered ticks from 13,260 migratory passerine birds in Sweden. A total of 1127 Ixodes spp. ticks were removed from these birds and the extracted DNA from 957 of them was available for analyses. The DNA was assayed for detection of Rickettsia spp. using real-time PCR, followed by DNA sequencing for species identification. Rickettsia spp. organisms were detected in 108 (11.3%) of the ticks. Rickettsia helvetica, a spotted fever rickettsia associated with human infections, was predominant among the PCR-positive samples. In 9 (0.8%) of the ticks, the partial sequences of 17kDa and ompB genes showed the greatest similarity to Rickettsia monacensis, an etiologic agent of Mediterranean spotted fever-like illness, previously described in southern Europe as well as to the Rickettsia sp.IrITA3 strain. For 15 (1.4%) of the ticks, the 17kDa, ompB, gltA and ompA genes showed the greatest similarity to Rickettsia sp. strain Davousti, Rickettsia japonica and Rickettsia heilongjiangensis, all closely phylogenetically related, the former previously found in Amblyomma tholloni ticks in Africa and previously not detected in Ixodes spp. ticks. The infestation prevalence of ticks infected with rickettsial organisms was four times higher among ground foraging birds than among other bird species, but the two groups were equally competent in transmitting Rickettsia species. The birds did not seem to serve as reservoir hosts for Rickettsia spp., but in one case it seems likely that the bird was rickettsiemic and that the ticks had acquired the bacteria from the blood of the bird. In conclusion, migratory passerine birds host epidemiologically important vector ticks and Rickettsia species and contribute to the geographic distribution of spotted fever rickettsial agents and their diseases.

  • 45.
    Elfving, Karin
    et al.
    Uppsala University Hospital ; Falu Hospital.
    Olsen, Björn
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Uppsala University Hospital.
    Bergström, Sven
    Umeå University.
    Waldenström, Jonas
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences. Uppsala University Hospital.
    Lundkvist, Åke
    Swedish Institute for Infectious Disease Control.
    Sjöstedt, Anders
    Umeå University Hospital.
    Mejlon, Hans
    Uppsala University.
    Nilsson, Kenneth
    Uppsala University Hospital ; Falu Hospital ; Uppsala University.
    Dissemination of Spotted Fever Rickettsia Agents in Europe by Migrating Birds2010In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 5, no 1, article id e8572Article in journal (Refereed)
    Abstract [en]

    Migratory birds are known to play a role as long-distance vectors for many microorganisms. To investigate whether this is true of rickettsial agents as well, we characterized tick infestation and gathered ticks from 13,260 migratory passerine birds in Sweden. A total of 1127 Ixodes spp. ticks were removed from these birds and the extracted DNA from 957 of them was available for analyses. The DNA was assayed for detection of Rickettsia spp. using real-time PCR, followed by DNA sequencing for species identification. Rickettsia spp. organisms were detected in 108 (11.3%) of the ticks. Rickettsia helvetica, a spotted fever rickettsia associated with human infections, was predominant among the PCR-positive samples. In 9 (0.8%) of the ticks, the partial sequences of 17kDa and ompB genes showed the greatest similarity to Rickettsia monacensis, an etiologic agent of Mediterranean spotted fever-like illness, previously described in southern Europe as well as to the Rickettsia sp. IrITA3 strain. For 15 (1.4%) of the ticks, the 17kDa, ompB, gltA and ompA genes showed the greatest similarity to Rickettsia sp. strain Davousti, Rickettsia japonica and Rickettsia heilongjiangensis, all closely phylogenetically related, the former previously found in Amblyomma tholloni ticks in Africa and previously not detected in Ixodes spp. ticks. The infestation prevalence of ticks infected with rickettsial organisms was four times higher among ground foraging birds than among other bird species, but the two groups were equally competent in transmitting Rickettsia species. The birds did not seem to serve as reservoir hosts for Rickettsia spp., but in one case it seems likely that the bird was rickettsiemic and that the ticks had acquired the bacteria from the blood of the bird. In conclusion, migratory passerine birds host epidemiologically important vector ticks and Rickettsia species and contribute to the geographic distribution of spotted fever rickettsial agents and their diseases.

  • 46.
    Ellström, Patrik
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Jourdain, Elsa
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Gunnarsson, Oskar
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    The ”human influenza receptor” Neu5Ac alpha 2,6Gal is expressed among different taxa of wild birds2009In: Archives of Virology, ISSN 0304-8608, E-ISSN 1432-8798, Vol. 154, no 9, p. 1533-1537Article in journal (Refereed)
  • 47.
    Ellström, Patrik
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Latorre-Margalef, Neus
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Griekspoor, Petra
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Olofsson, Jenny
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Wahlgren, John
    Ctr Microbiol Preparedness KCB, Swedish Inst Infect Dis Control SMI, SE-17182 Solna, Sweden.
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Sampling for low-pathogenic avian influenza A virus in wild Mallard ducks: Oropharyngeal versus cloacal swabbing2008In: Vaccine, ISSN 0264-410X, E-ISSN 1873-2518, Vol. 26, no 35, p. 4414-4416Article in journal (Refereed)
  • 48.
    Eriksson, Per
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Lindskog, Cecilia
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical and experimental pathology.
    Lorente-Leal, Victor
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Waldenström, Jonas
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, Kalmar, Sweden.
    González-Acuna, Daniel
    Univ Concepcion, Fac Ciencias Vet, Chillan, Chile.
    Järhult, Josef D.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine.
    Lundkvist, Åke
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine.
    Jourdain, Elsa
    INRA, UMR0346 EPIA, VetAgro Sup, St Genes Champanelle, France.
    Ellström, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine.
    Attachment Patterns of Human and Avian Influenza Viruses to Trachea and Colon of 26 Bird Species: Support for the Community Concept2019In: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 10, article id 815Article in journal (Refereed)
    Abstract [en]

    Avian influenza A viruses (AIVs) have a broad host range, but are most intimately associated with waterfowl (Anseriformes) and, in the case of the H13 and H16 subtypes, gulls (Charadriiformes). Host associations are multifactorial, but a key factor is the ability of the virus to bind host cell receptors and thereby initiate infection. The current study aims at investigating the tissue attachment pattern of a panel of AIVs, comprising H3N2, H6N1, H12N5, and H16N3, to avian trachea and colon tissue samples obtained from host species of different orders. Virus attachment was not restricted to the bird species or order from which the virus was isolated. Instead, extensive virus attachment was observed to several distantly related avian species. In general, more virus attachment and receptor expression were observed in trachea than in colon samples. Additionally, a human seasonal H3N2 virus was studied. Unlike the studied AIVs, this virus mainly attached to tracheae from Charadriiformes and a very limited set of avian cola. In conclusion, the reported results highlight the importance of AIV attachment to trachea in many avian species. Finally, the importance of chickens and mallards in AIVs dynamics was illustrated by the abundant AIV attachment observed.

  • 49. Fick, Jerker
    et al.
    Lindberg, Richard H.
    Tysklind, Mats
    Haemig, Paul D.
    Waldenström, Jonas
    Wallensten, Anders
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Antiviral Oseltamivir is not removed or degraded in normal sewage water treatment: Implications for development of resistance by influenza A virus2007In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 2, no 10, p. e986-Article in journal (Refereed)
    Abstract [en]

    Oseltamivir is the main antiviral for treatment and prevention of pandemic influenza. The increase in oseltamivir resistance reported recently has therefore sparked a debate on how to use oseltamivir in non pandemic influenza and the risks associated with wide spread use during a pandemic. Several questions have been asked about the fate of oseltamivir in the sewage treatment plants and in the environment. We have assessed the fate of oseltamivir and discuss the implications of environmental residues of oseltamivir regarding the occurrence of resistance. A series of batch experiments that simulated normal sewage treatment with oseltamivir present was conducted and the UV-spectra of oseltamivir were recorded. Findings: Our experiments show that the active moiety of oseltamivir is not removed in normal sewage water treatments and is not degraded substantially by UV light radiation, and that the active substance is released in waste water leaving the plant. Our conclusion is that a ubiquitous use of oseltamivir may result in selection pressures in the environment that favor development of drug-resistance.

  • 50. Fouchier, R A M
    et al.
    Munster, V
    Wallensten, Anders
    Bestebroer, T M
    Herfst, S
    Smith, D
    Rimmelzwaan, G F
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Osterhaus, A D M E
    Characterization of a novel influenza a virus hemagglutinin subtype (H16) obtained from black-headed gulls2005In: Journal of virology, Vol. 79 (5), p. 2814-2822Article in journal (Refereed)
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