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  • 1.
    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.

  • 2.
    Dicksved, Johan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Ellström, Patrik
    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.
    Engstrand, Lars
    Rautelin, Hilpi
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine.
    Susceptibility to Campylobacter Infection Is Associated with the Species Composition of the Human Fecal Microbiota2014In: mBio, ISSN 2161-2129, E-ISSN 2150-7511, Vol. 5, no 5, p. e01212-14-Article in journal (Refereed)
    Abstract [en]

    The gut microbiota is essential for human health, but very little is known about how the composition of this ecosystem can influence and respond to bacterial infections. Here we address this by prospectively studying the gut microbiota composition before, during, and after natural Campylobacter infection in exposed poultry abattoir workers. The gut microbiota composition was analyzed with 16S amplicon sequencing of fecal samples from poultry abattoir workers during the peak season of Campylobacter infection in Sweden. The gut microbiota compositions were compared between individuals who became culture positive for Campylobacter and those who remained negative. Individuals who became Campylobacter positive had a significantly higher abundance of Bacteroides (P = 0.007) and Escherichia (P = 0.002) species than those who remained culture negative. Furthermore, this group had a significantly higher abundance of Phascolarctobacterium (P = 0.017) and Streptococcus (P = 0.034) sequences than the Campylobacter-negative group, which had an overrepresentation of Clostridiales (P = 0.017), unclassified Lachnospiraceae (P = 0.008), and Anaerovorax (P = 0.015) sequences. Intraindividual comparisons of the fecal microbiota compositions yielded small differences over time in Campylobacter-negative participants, but significant long-term changes were found in the Campylobacter-positive group (P < 0.005). The results suggest that the abundance of specific genera in the microbiota reduces resistance to Campylobacter colonization in humans and that Campylobacter infection can have long-term effects on the composition of the human fecal microbiota. IMPORTANCE Studies using mouse models have made important contributions to our understanding of the role of the gut microbiota in resistance to bacterial enteropathogen colonization. The relative abundances of Escherichia coli and Bacteroides species have been pointed out as important determinants of susceptibility to Gram-negative pathogens in general and Campylobacter infection in particular. In this study, we assessed the role of the human gut microbiota in resistance to Campylobacter colonization by studying abattoir workers that are heavily exposed to these bacteria. Individuals with a certain composition of the gut microbiota became culture positive for Campylobacter. As their microbiotas were characterized by high abundances of Bacteroides spp. and E. coli, well in line with the findings with mouse models, these bacterial species likely play an important role in colonization resistance also in humans.

  • 3. Ekstam, Börje
    et al.
    Johansson, Beatha
    Dinnétz, Patrik
    Ellström, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology.
    Predicting risk habitats for the transmission of the small liver fluke, Dicrocoelium dendriticum to grazing ruminants2011In: Geospatial health: Health applications in Geospatial Science, ISSN 1970-7096, Vol. 6, no 1, p. 125-131Article in journal (Refereed)
    Abstract [en]

    A multiple regression model was used to analyse if the structure of vegetation and soil patches in grazed units (pastures) can be used as explanatory variables to predict the prevalence of Dicrocoelium dendriticum, a common parasite of cattle and sheep, in grazing cattle stocks on the Baltic island of Öland in southern Sweden. The scale dependency was evaluated by comparing three levels of spatial resolution of patches. Prevalence data were obtained from slaughtered animals. Our models predict that the prevalence of D. dendriticum increases in grazed areas with woody vegetation, whereas moist and wet areas decrease parasite prevalence. The predictive power of the statistical models increased with increasing level of patch resolution. Approximately 42% of the variation in parasite prevalence (angular transformation) was explained by the areal proportion of vegetation types (4th-root-transformed). Based on the results obtained, we believe that our model strategy provides a rational and systematic tool to identify habitats that carry risk for D. dendriticum infection of ruminants, and that it can be applied to other parasites with similar life cycles such as Fasciola hepatica.

  • 4.
    Ellström, Patrik
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Feodoroff, B.
    Hanninen, M. -L
    Rautelin, Hilpi
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Lipooligosaccharide locus class of Campylobacter jejuni: sialylation is not needed for invasive infection2014In: Clinical Microbiology and Infection, ISSN 1198-743X, E-ISSN 1469-0691, Vol. 20, no 6, p. 524-529Article in journal (Refereed)
    Abstract [en]

    Campylobacter jejuni is a highly diverse enteropathogen that is commonly detected worldwide. It can sometimes cause bacteraemia, but the bacterial characteristics facilitating bloodstream infection are not known. A total of 73 C. jejuni isolates, consecutively collected from blood-borne infections during a 10-year period all over Finland and for which detailed clinical information of the patients were available, were included. We screened the isolates by PCR for the lipooligosaccharide (LOS) locus class and for the presence of the putative virulence genes ceuE, ciaB, fucP, and virB11. The isolates were also tested for gamma-glutamyl transpeptidase production. The results were analysed with respect to the clinical characteristics of the patients, and the multilocus sequence types (MLSTs) and serum resistance of the isolates. LOS locus classes A, B, and C, which carry genes for sialylation of LOS, were detected in only 23% of the isolates. These isolates were not more resistant to human serum than those with the genes of non-sialylated LOS locus classes, but were significantly more prevalent among patients with underlying diseases (p 0.02). The fucose permease gene fucP was quite uncommon, but was associated with the isolates with the potential to sialylate LOS (p <0.0001). LOS locus classes and some of the putative virulence factors were associated with MLST clonal complexes. Although some of the bacterial characteristics studied here have been suggested to be important for the invasiveness of C. jejuni, they did not explain why the clinical isolates in the present study were able to cause bacteraemia.

  • 5.
    Ellström, Patrik
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Feodoroff, Benjamin
    Hanninen, Marja-Liisa
    Rautelin, Hilpi
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Characterization of clinical Campylobacter jejuni isolates with special emphasis on lipooligosaccharide locus class, putative virulence factors and host response2013In: International Journal of Medical Microbiology, ISSN 1438-4221, E-ISSN 1618-0607, Vol. 303, no 3, p. 134-139Article in journal (Refereed)
    Abstract [en]

    Recent studies have indicated a role of the lipooligosaccharide (LOS) of Campylobacter jejuni in the severe neurological Guillain Barre syndrome, as well as in development of more severe symptoms of acute enteritis. We evaluated the role of the LOS locus class in C jejuni infection among 163 enteritis patients. The prevalence of LOS locus classes differed according to the origin of the isolates. Furthermore, LOS locus classes A and B were significantly associated with susceptibility or resistance to ciprofloxacin and doxycycline. However, our results do not corroborate earlier findings that isolates with potential to sialylate LOS might be associated with more severe symptoms of enteritis. Instead, in an infection model, such isolates gave weaker epithelial IL-8 responses than nonsialylated isolates. Absence of the iron transport protein encoded by the gene ceuE as well as the putative fucose permease gene cj0486 was associated with increased in vitro IL-8 secretion. 

  • 6.
    Ellström, Patrik
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Hansson, Ingrid
    Natl Vet Inst, EU Reference Lab Campylobacter, Dept Microbiol, SE-75189 Uppsala, Sweden..
    Nilsson, Anna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Rautelin, Hilpi
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology. Univ Helsinki, Dept Bacteriol & Immunol, POB 21, FIN-00014 Helsinki, Finland..
    Engvall, Eva Olsson
    Natl Vet Inst, EU Reference Lab Campylobacter, Dept Microbiol, SE-75189 Uppsala, Sweden..
    Lipooligosaccharide locus classes and putative virulence genes among chicken and human Campylobacter jejuni isolates2016In: BMC Microbiology, ISSN 1471-2180, E-ISSN 1471-2180, Vol. 16, article id 116Article in journal (Refereed)
    Abstract [en]

    Background: Campylobacter cause morbidity and considerable economic loss due to hospitalization and post infectious sequelae such as reactive arthritis, Guillain Barr-and Miller Fischer syndromes. Such sequelae have been linked to C. jejuni harboring sialic acid structures in their lipooligosaccharide (LOS) layer of the cell wall. Poultry is an important source of human Campylobacter infections but little is known about the prevalence of sialylated C. jejuni isolates and the extent of transmission of such isolates to humans. Results: Genotypes of C. jejuni isolates from enteritis patients were compared with those of broiler chicken with pulsed-field gel electrophoresis (PFGE), to study the patterns of LOS biosynthesis genes and other virulence associated genes and to what extent these occur among Campylobacter genotypes found both in humans and chickens. Chicken and human isolates generally had similar distributions of the putative virulence genes and LOS locus classes studied. However, there were significant differences regarding LOS locus class of PFGE types that were overlapping between chicken and human isolates and those that were distinct to each source. Conclusions: The study highlights the prevalence of virulence associated genes among Campylobacter isolates from humans and chickens and suggests possible patterns of transmission between the two species.

  • 7.
    Ellström, Patrik
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine.
    Hansson, Ingrid
    Soderstrom, Claes
    Engvall, Eva Olsson
    Rautelin, Hilpi
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine.
    A Prospective Follow-Up Study on Transmission of Campylobacter from Poultry to Abattoir Workers2014In: Foodborne Pathogens and Disease, ISSN 1535-3141, Vol. 11, no 9, p. 684-688Article in journal (Refereed)
    Abstract [en]

    Contact with poultry or poultry meat is a well-known risk factor for campylobacteriosis, but prospective studies on transmission of Campylobacter from chickens to humans during slaughter are scarce. In this study, we monitored transmission of Campylobacter from slaughtered chicken to originally culture-negative abattoir workers during the peak season of colonized chicken and human Campylobacter infection. Stool samples were obtained from 28 abattoir workers together with data on health status once a month between June and September 2010, with a follow-up sample collected in February 2011. Campylobacter-positive individuals and chicken flocks were identified by culture, and isolates were further characterized using molecular techniques. Campylobacter was isolated from seven asymptomatic individuals. Four of them had been newly employed and had not reported any previous Campylobacter infection. Four human isolates had matching genetic fingerprints with isolates from recently slaughtered chickens. Our results further support the role of chicken as the source of human Campylobacter infection but suggest that asymptomatic Campylobacter infection may occur even in individuals with only limited earlier exposure to Campylobacter.

  • 8.
    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.

  • 9. Feodoroff, Benjamin
    et al.
    de Haan, Caroline P. A.
    Ellstrom, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine.
    Sarna, Seppo
    Hanninen, Marja-Liisa
    Rautelin, Hilpi
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine.
    Clonal Distribution and Virulence of Campylobacter jejuni Isolates in Blood2013In: Emerging Infectious Diseases, ISSN 1080-6040, E-ISSN 1080-6059, Vol. 19, no 10, p. 1653-1655Article in journal (Refereed)
    Abstract [en]

    Campylobacter jejuni bacteria are highly diverse enteropathogens. Seventy-three C. jejuni isolates from blood collected in Finland were analyzed by multilocus sequence typing and serum resistance. Approximately half of the isolates belonged to the otherwise uncommon sequence type 677 clonal complex. Isolates of this clonal complex were more resistant than other isolates to human serum.

  • 10. Feodoroff, Benjamin
    et al.
    Ellström, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology.
    Hyytiainen, Heidi
    Sarna, Seppo
    Hanninen, Marja-Liisa
    Rautelin, Hilpi
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology.
    Campylobacter jejuni isolates in Finnish patients differ according to the origin of infection2010In: Gut Pathogens, ISSN 1757-4749, Vol. 2, no 1, article id 22Article in journal (Refereed)
    Abstract [en]

    ABSTRACT: BACKGROUND: Campylobacter jejuni is a significant cause of bacterial enteritis worldwide. Very little is known about the pathogenicity mechanisms and virulence factors of this important enteropathogen. C. jejuni isolates from 166 Finnish patients, collected from July to December in 2006, were studied for the presence of putative virulence factors and susceptibility to antimicrobials. Isolates were tested for production of gamma-glutamyltransferase (GGT) as well as the presence of genes ceuE, cgtB, ciaB, cj0486, pldA, virB11, wlaN, and the gene cluster cdtABC. Bacterial characteristics were compared to information on foreign travel history as well as information on the course and the symptoms of disease obtained from questionnaires returned by patients. RESULTS: Except for one domestic isolate, antimicrobial resistance was only detected in isolates of foreign origin. Univariate analyses showed association between bloody stools and both GGT production (p=0.025) and the presence of cgtB (p=0.034). Multivariate analysis verified that GGT production was more prevalent in domestic isolates (p<0.0001), while the genes cj0486 (p<0.0001) and ceuE (p<0.0001) were associated with C. jejuni isolates of foreign origin. CONCLUSIONS: The results indicate that imported and domestic C. jejuni isolates differ significantly in several aspects from each other.

  • 11. Feodoroff, Benjamin
    et al.
    Lauhio, Anneli
    Ellström, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology.
    Rautelin, Hilpi
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology.
    A Nationwide Study of Campylobacter jejuni and Campylobacter coli Bacteremia in Finland over a 10-Year Period, 1998-2007, with Special Reference to Clinical Characteristics and Antimicrobial Susceptibility2011In: Clinical Infectious Diseases, ISSN 1058-4838, E-ISSN 1537-6591, Vol. 53, no 8, p. e99-e106Article in journal (Refereed)
    Abstract [en]

    Background: Campylobacter bacteremia is an uncommon condition, usually diagnosed in elderly and immunocompromised patients.

    Methods: Blood culture isolates and clinical information were collected for patients with diagnoses of Campylobacter jejuni or Campylobacter coli bacteremia in Finland from 1998 through 2007. Bacterial species were identified by means of polymerase chain reaction analysis, and minimal inhibitory concentrations for ciprofloxacin, clindamycin, doxycycline, erythromycin, gentamicin, meropenem, and metronidazole were determined with an agar dilution method. Medical records and mortality data within 1 year after the bacteremic episode were reviewed.

    Results: The study included 76 patients (median age, 46 years), for whom bacterial isolates (C. jejuni in 73, C. coli in 3) and clinical information were available. Most patients (70%) had no significant underlying diseases. The majority (82%) of the isolates were susceptible for all antimicrobial agents tested. However, antimicrobial therapy seemed to have only a limited effect, because no differences could be detected between patients with appropriate empirical antimicrobial treatment and those with delayed appropriate, inappropriate, or no antimicrobial therapy, either in the duration of hospitalization (median, 4 days for both groups) or in attributable mortality. The outcome of the infection was severe in 4 patients infected with C. jejuni; 2 died within 30 days, spondylodiscitis developed in 1, and Guillain-Barré syndrome developed in 1.

    Conclusions: C. jejuni and C. coli bacteremia occurred mainly in moderately young individuals without severe underlying diseases. The bacterial isolates were predominantly susceptible to antimicrobial agents, and the outcome of the disease was typically good, regardless of appropriate or inappropriate antimicrobial treatment given in the hospital.

  • 12.
    Johansson, Håkan
    et al.
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, Kalmar, Sweden.
    Ellström, Patrik
    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, Infection medicine.
    Artursson, Karin
    National Veterinary Institute, Uppsala, Sweden.
    Berg, Charlotte
    Swedish Univ Agr Sci, Dept Anim Environm & Hlth, Skara, Sweden.
    Bonnedahl, Jonas
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, Kalmar, Sweden;Kalmar Cty Hosp, Dept Infect Dis, Kalmar, Sweden.
    Hansson, Ingrid
    Swedish Univ Agr Sci, Dept Biomed Sci & Vet Publ Hlth, Uppsala, Sweden.
    Hernandez, Jorge
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. Kalmar Cty Hosp, Lab Microbiol, Kalmar, Sweden.
    Lopez-Martin, Juana
    Univ Concepcion, Fac Ciencias & Vet, Dept Patol & Med Prevent, Chillan, Chile.
    Medina-Vogel, Gonzalo
    Univ Andres Bello, Ctr Invest Sustentabilidad, Santiago, Chile.
    Moreno, Lucile
    Univ Concepcion, Fac Ciencias Nat & Oceanograf, Concepcion, Chile.
    Olsen, Björn
    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, Infection medicine.
    Engvall, Eva Olsson
    National Veterinary Institute, Uppsala, Sweden.
    Skarin, Hanna
    National Veterinary Institute, Uppsala, Sweden.
    Troell, Karin
    Natl Vet Inst, Uppsala, Sweden.
    Waldenström, Jonas
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, Kalmar, Sweden.
    Ågren, Joakim
    National Veterinary Institute, Uppsala, Sweden.
    Gonzalez-Acuna, Daniel
    Univ Concepcion, Fac Ciencias Vet, Chillan, Chile.
    Characterization of Campylobacter spp. isolated from wild birds in the Antarctic and Sub-Antarctic2018In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 13, no 11, article id e0206502Article in journal (Refereed)
    Abstract [en]

    A lack of knowledge of naturally occurring pathogens is limiting our ability to use the Antarctic to study the impact human-mediated introduction of infectious microorganisms have on this relatively uncontaminated environment. As no large-scale coordinated effort to remedy this lack of knowledge has taken place, we rely on smaller targeted efforts to both study present microorganisms and monitor the environment for introductions. In one such effort, we isolated Campylobacter species from fecal samples collected from wild birds in the Antarctic Peninsula and the sub-Antarctic island of South Georgia. Indeed, in South Georgia, we found Campylobacter lari and the closely related Campylobacter peloridis, but also distantly related human-associated multilocus sequence types of Campylobacter jejuni. In contrast, in the Antarctic Peninsula, we found C. tart and two closely related species, Campylobacter subantarcticus and Campylobacter volucris, but no signs of human introduction. In fact, our finding of human-associated sequence types of C. jejuni in South Georgia, but not in the Antarctic Peninsula, suggests that efforts to limit the spread of infectious microorganisms to the Antarctic have so far been successful in preventing the introduction of C. jejuni. However, we do not know how it came to South Georgia and whether the same mode of introduction could spread it from there to the Antarctic Peninsula.

  • 13. Jourdain, Elsa
    et al.
    van Riel, Debby
    Munster, Vincent J.
    Kuiken, Thijs
    Waldenstrom, Jonas
    Olsen, Bjorn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Ellström, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology.
    The Pattern of Influenza Virus Attachment Varies among Wild Bird Species2011In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, no 9, p. e24155-Article in journal (Refereed)
    Abstract [en]

    The ability to attach to host cells is one of the main determinants of the host range of influenza A viruses. By using virus histochemistry, we investigate the pattern of virus attachment of both a human and an avian influenza virus in colon and trachea sections from 12 wild bird species. We show that significant variations exist, even between closely related avian species, which suggests that the ability of wild birds to serve as hosts for influenza viruses strongly varies among species. These results will prove valuable to assess the possibilities of interspecies transmission of influenza viruses in natural environments and better understand the ecology of influenza.

  • 14.
    Lindskog, Cecilia
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Ellström, Patrik
    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, Infectious Diseases.
    Pontén, Fredrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Molecular and Morphological Pathology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    van Riel, Debby
    Munster, Vincent J
    González-Acuña, Daniel
    Kuiken, Thijs
    Jourdain, Elsa
    European H16N3 Gull Influenza Virus Attaches to the Human Respiratory Tract and Eye2013In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, no 4, p. e60757-Article in journal (Refereed)
    Abstract [en]

    We explored the attachment of an H16N3 influenza virus to human, mallard, and gull tissues using virus histochemistry applied to tissue microarrays and employing human and mallard viruses as references. Of the viruses tested, the H16N3 gull virus most readily attached to the human respiratory tract and eye. These results underscore the need to assess the potential for gull influenza viruses to replicate in human tissues and further investigate the role of gulls in influenza virus ecology.

  • 15.
    Olofsson, Jenny
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Axelsson-Olsson, Diana
    Brudin, Lars
    Olsen, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases.
    Ellström, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Campylobacter jejuni Actively Invades the Amoeba Acanthamoeba polyphaga and Survives within Non Digestive Vacuoles2013In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, no 11, p. e78873-Article in journal (Refereed)
    Abstract [en]

    The Gram-negative bacterium Campylobacter jejuni is able to enter, survive and multiply within the free living amoeba Acanthamoeba polyphaga, but the molecular mechanisms behind these events are still unclear. We have studied the uptake and intracellular trafficking of viable and heat killed bacterial cells of the C. jejuni strain 81-176 in A. polyphaga. We found that viable bacteria associated with a substantially higher proportion of Acanthamoeba trophozoites than heat killed bacteria. Furthermore, the kinetics of internalization, the total number of internalized bacteria as well as the intracellular localization of internalized C. jejuni were dramatically influenced by bacterial viability. Viable bacteria were internalized at a high rate already after 1 h of co-incubation and were observed in small vacuoles tightly surrounding the bacteria. In contrast, internalization of heat killed C. jejuni was low at early time points and did not peak until 96 h. These cells were gathered in large spacious vacuoles that were part of the degradative pathway as determined by the uptake of fluorescently labeled dextran. The amount of heat killed bacteria internalized by A. polyphaga did never reach the maximal amount of internalized viable bacteria. These results suggest that the uptake and intracellular survival of C. jejuni in A. polyphaga is bacterially induced.

  • 16.
    Osbjer, Kristina
    et al.
    Swedish Univ Agr Sci, Div Reprod, Dept Clin Sci, Box 7054, SE-75007 Uppsala, Sweden..
    Tano, Eva
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine.
    Chhayheng, Leang
    Natl Inst Publ Hlth, Phnom Penh, Cambodia..
    Mac-Kwashie, Akofa Olivia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Fernstrom, Lise-Lotte
    Swedish Univ Agr Sci, Dept Biomed Sci & Vet Publ Hlth, Uppsala, Sweden..
    Ellström, Patrik
    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.
    Sokerya, Seng
    Ctr Livestock & Agr Dev, Phnom Penh, Cambodia..
    Sokheng, Choup
    Natl Inst Publ Hlth, Phnom Penh, Cambodia..
    Mom, Veng
    Natl Inst Publ Hlth, Phnom Penh, Cambodia..
    Chheng, Kannarath
    Natl Inst Publ Hlth, Phnom Penh, Cambodia..
    San, Sorn
    Natl Inst Vet Res, Phnom Penh, Cambodia..
    Davun, Holl
    Natl Inst Vet Res, Phnom Penh, Cambodia..
    Boqvist, Sofia
    Swedish Univ Agr Sci, Dept Biomed Sci & Vet Publ Hlth, Uppsala, Sweden..
    Rautelin, Hilpi
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Magnusson, Ulf
    Swedish Univ Agr Sci, Div Reprod, Dept Clin Sci, Box 7054, SE-75007 Uppsala, Sweden..
    Detection of Campylobacter in human and animal field samples in Cambodia2016In: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), ISSN 0903-4641, E-ISSN 1600-0463, Vol. 124, no 6, p. 508-515Article in journal (Refereed)
    Abstract [en]

    Campylobacter are zoonotic bacteria and a leading cause of human gastroenteritis worldwide with Campylobacter jejuni and C. coli being the most commonly detected species. The aim of this study was to detect Campylobacter in humans and livestock (chickens, ducks, pigs, cattle, water buffalo, quail, pigeons and geese) in rural households by routine culturing and multiplex PCR in faecal samples frozen before analysis. Of 681 human samples, 82 (12%) tested positive by PCR (C. jejuni in 66 samples and C. coli in 16), but none by routine culture. Children were more commonly Campylobacter positive (19%) than adult males (8%) and females (7%). Of 853 livestock samples, 106 (12%) tested positive by routine culture and 352 (41%) by PCR. Campylobacter jejuni was more frequent in chickens and ducks and C. coli in pigs. In conclusion, Campylobacter proved to be highly prevalent by PCR in children (19%), ducks (24%), chickens (56%) and pigs (72%). Routine culturing was insufficiently sensitive in detecting Campylobacter in field samples frozen before analysis. These findings suggest that PCR should be the preferred diagnostic method for detection of Campylobacter in humans and livestock where timely culture is not feasible.

  • 17.
    Persson, Sofia
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Eriksson, Ronnie
    Lowther, James
    Ellström, Patrik
    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, Infection medicine.
    Simonsson, Magnus
    Comparison between RT droplet digital PCR and RT real-time PCR for quantification of noroviruses in oysters.2018In: International Journal of Food Microbiology, ISSN 0168-1605, E-ISSN 1879-3460, Vol. 284, p. 73-83Article in journal (Refereed)
    Abstract [en]

    Oysters are frequently associated with norovirus outbreaks, but the presence of norovirus RNA in oysters does not necessarily imply a health risk to humans. There is a close link between human illness and consumption of oysters with high levels of norovirus RNA, but oysters with low levels of norovirus RNA are more unlikely to be associated with illness. Reliable and precise quantification methods are therefore important for outbreak investigations and risk assessments. This study optimised and validated RT droplet digital PCR (RT-ddPCR) assays for quantification of norovirus genogroups I and II in artificially contaminated oysters, and compared them with the standard method, RT real-time PCR (RT-qPCR). The two methods had comparable 95% limits of detection, but RT-ddPCR generally showed greater precision in quantification. Differences between fluorometric measurements and quantification with RT-ddPCR were determined on in vitro transcribed RNA with targets for norovirus genogroups I and II. Quantification by RT-ddPCR was on average 100 times lower than the fluorometric value for norovirus GI and 15.8 times lower than the fluorometric value for norovirus GII. The large inter-assay difference observed highlights the need for monitoring the RT efficiency in RT-ddPCR, especially when results from different assays are compared. Overall, this study suggests that RT-ddPCR can be a suitable method for precise quantification of norovirus genogroups I and II in oysters.

  • 18.
    Persson, Sofia
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine. Natl Food Agcy, European Union Reference Lab EURL Foodborne Viru, Hamnesplanaden 5, S-45323 Uppsala, Sweden.
    Karlsson, Mans
    Stockholm Univ, Dept Math, Stockholm, Sweden.
    Borsch-Reniers, Henrik
    Southern Roslagen Environm & Hlth Author, Taby, Sweden.
    Ellström, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine.
    Eriksson, Ronnie
    Natl Food Agcy, European Union Reference Lab EURL Foodborne Viru, Hamnesplanaden 5, S-45323 Uppsala, Sweden.
    Simonsson, Magnus
    Natl Food Agcy, European Union Reference Lab EURL Foodborne Viru, Hamnesplanaden 5, S-45323 Uppsala, Sweden.
    Missing the Match Might Not Cost You the Game: Primer-Template Mismatches Studied in Different Hepatitis A Virus Variants2019In: Food and Environmnetal Virology, ISSN 1867-0334, E-ISSN 1867-0342, Vol. 11, no 3, p. 297-308Article in journal (Refereed)
    Abstract [en]

    Mismatches between template sequences and reverse transcription (RT) or polymerase chain reaction (PCR) primers can lead to underestimation or false negative results during detection and quantification of sequence-diverse viruses. We performed an in silico inclusivity analysis of a widely used RT-PCR assay for detection of hepatitis A virus (HAV) in food, described in ISO 15216-1. One of the most common mismatches found was a single G (primer) to U (template) mismatch located at the terminal 3 '-end of the reverse primer region. This mismatch was present in all genotype III sequences available in GenBank. Partial HAV genomes with common or potentially severe mismatches were produced by in vitro transcription and analysed using RT-ddPCR and RT-qPCR. When using standard conditions for RT-qPCR, the mismatch identified resulted in underestimation of the template concentration by a factor of 1.7-1.8 and an increase in 95% limit of detection from 8.6 to 19 copies/reaction. The effect of this mismatch was verified using full-length viral genomes. Here, the same mismatch resulted in underestimation of the template concentration by a factor of 2.8. For the partial genomes, the presence of additional mismatches resulted in underestimation of the template concentration by up to a factor of 232. Quantification by RT-ddPCR and RT-qPCR was equally affected during analysis of RNA templates with mismatches within the reverse primer region. However, on analysing DNA templates with the same mismatches, we found that ddPCR quantification was less affected by mismatches than qPCR due to the end-point detection technique.

  • 19. Revez, Joana
    et al.
    Rossi, Mirko
    Ellström, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology.
    de Haan, Caroline
    Rautelin, Hilpi
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Bacteriology.
    Hänninen, Marja-Liisa
    Finnish Campylobacter jejuni Strains of Multilocus Sequence Type ST-22 Complex Have Two Lineages with Different Characteristics2011In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, no 10, p. e26880-Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Campylobacter jejuni is the major cause of human bacterial gastroenteritis worldwide, and in a minority of cases, post-infectious complications may occur. ST-22 complex (usually Penner serotype 19) strains have been overrepresented among patients with postinfectious complications of campylobacteriosis. We here present a characterization of a collection of 27 Finnish C. jejuni strains of ST-22 complex, from humans (22 strains) and animal sources (five strains), with the aim of contributing to our knowledge of the pathogenesis of C. jejuni infections.

    METHODOLOGY/PRINCIPAL FINDINGS: All strains were analyzed by pulsed-field gel electrophoresis (PFGE) genotyping, lipo-oligosaccharide (LOS) locus class, Y-glutamyl transpeptidase (GGT) activity, in vitro biofilm formation ability, invasion and adhesion in HeLa cells and induction of IL-8 production. ST-22 complex contained five STs (ST-22; ST-1947; ST-1966; ST-3892; ST-3996) which were homogeneous in having sialylated LOS class A(1) but on the other hand were distinguished into two major lineages according to the major STs (ST-22 and ST-1947) by different PFGE genotypes and certain other characteristics. All ST-22 strains had similar SmaI PFGE profiles, were GGT positive, and formed biofilms, except one strain, while ST-1947 strains were all GGT negative, did not form biofilm, had significantly higher motility than ST-22 (p<0.05) and had their SmaI PFGE profile. Invasion and adhesion as well as induction of IL-8 production on HeLa cells were strain-dependent characteristics.

    CONCLUSIONS/SIGNIFICANCE: ST-22 complex strains, reveal potential for molecular mimicry in host interactions upon infection as they all express sialylated LOS class A(1). The two major STs, ST-22 and ST-1947 formed two homogeneous lineages, which differed from each other both phenotypically and genetically, suggesting that the strains may have evolved separately, perhaps by interacting with different spectra of hosts. Further studies are needed in order to understand if these two lineages are associated with different disease outcomes.

  • 20.
    Skarp, Astrid
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Akinrinade, O.
    Univ Helsinki, Inst Clin Med, Helsinki, Finland.;Univ Helsinki, Inst Biomed, Helsinki, Finland..
    Nilsson, Anna J. E.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Ellström, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Myllykangas, S.
    Univ Helsinki, Inst Biomed, Helsinki, Finland..
    Rautelin, Hilpi
    Univ Helsinki, Dept Bacteriol & Immunol, Helsinki, Finland..
    Comparative genomics and genome biology of invasive Campylobacter jejuni2015In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, article id 17300Article in journal (Refereed)
    Abstract [en]

    Campylobacter jejuni is a major pathogen in bacterial gastroenteritis worldwide and can cause bacteremia in severe cases. C. jejuni is highly structured into clonal lineages of which the ST677CC lineage has been overrepresented among C. jejuni isolates derived from blood. In this study, we characterized the genomes of 31 C. jejuni blood isolates and 24 faecal isolates belonging to ST677CC in order to study the genome biology related to C. jejuni invasiveness. We combined the genome analyses with phenotypical evidence on serum resistance which was associated with phase variation of wcbK; a GDP-mannose 4,6-dehydratase involved in capsular biosynthesis. We also describe the finding of a Type III restriction-modification system unique to the ST-794 sublineage. However, features previously considered to be related to pathogenesis of C. jejuni were either absent or disrupted among our strains. Our results refine the role of capsule features associated with invasive disease and accentuate the possibility of methylation and restriction enzymes in the potential of C. jejuni to establish invasive infections. Our findings underline the importance of studying clinically relevant well-characterized bacterial strains in order to understand pathogenesis mechanisms important in human infections.

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