| 1. |
- Järhult, Josef D., et al.
(author)
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Environmental levels of the antiviral oseltamivir induce development of resistance mutation H274Y in influenza A/H1N1 virus in mallards
- 2011
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In: PLOS ONE. - San Francisco, CA : Public Library of Science (PLoS). - 1932-6203. ; 6:9
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Journal article (peer-reviewed)abstract
- Oseltamivir (Tamiflu®) is the most widely used drug against influenza infections and is extensively stockpiled worldwide as part of pandemic preparedness plans. However, resistance is a growing problem and in 2008-2009, seasonal human influenza A/H1N1 virus strains in most parts of the world carried the mutation H274Y in the neuraminidase gene which causes resistance to the drug. The active metabolite of oseltamivir, oseltamivir carboxylate (OC), is poorly degraded in sewage treatment plants and surface water and has been detected in aquatic environments where the natural influenza reservoir, dabbling ducks, can be exposed to the substance. To assess if resistance can develop under these circumstances, we infected mallards with influenza A/H1N1 virus and exposed the birds to 80 ng/L, 1 µg/L and 80 µg/L of OC through their sole water source. By sequencing the neuraminidase gene from fecal samples, we found that H274Y occurred at 1 µg/L of OC and rapidly dominated the viral population at 80 µg/L. IC₅₀ for OC was increased from 2-4 nM in wild-type viruses to 400-700 nM in H274Y mutants as measured by a neuraminidase inhibition assay. This is consistent with the decrease in sensitivity to OC that has been noted among human clinical isolates carrying H274Y. Environmental OC levels have been measured to 58-293 ng/L during seasonal outbreaks and are expected to reach µg/L-levels during pandemics. Thus, resistance could be induced in influenza viruses circulating among wild ducks. As influenza viruses can cross species barriers, oseltamivir resistance could spread to human-adapted strains with pandemic potential disabling oseltamivir, a cornerstone in pandemic preparedness planning. We propose surveillance in wild birds as a measure to understand the resistance situation in nature and to monitor it over time. Strategies to lower environmental levels of OC include improved sewage treatment and, more importantly, a prudent use of antivirals.
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| 2. |
- Gillman, Anna, et al.
(author)
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Oseltamivir-Resistant Influenza A (H1N1) Virus Strain with an H274Y Mutation in Neuraminidase Persists without Drug Pressure in Infected Mallards
- 2015
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In: Applied and Environmental Microbiology. - : American Society for Microbiology. - 0099-2240 .- 1098-5336. ; 81:7, s. 2378-2383
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Journal article (peer-reviewed)abstract
- Influenza A virus (IAV) has its natural reservoir in wild waterfowl, and emerging human IAVs often contain gene segments from avian viruses. The active drug metabolite of oseltamivir (oseltamivir carboxylate [OC]), stockpiled as Tamiflu for influenza pandemic preparedness, is not removed by conventional sewage treatment and has been detected in river water. There, it may exert evolutionary pressure on avian IAV in waterfowl, resulting in the development of resistant viral variants. A resistant avian IAV can circulate among wild birds only if resistance does not restrict viral fitness and if the resistant virus can persist without continuous drug pressure. In this in vivo mallard (Anas platyrhynchos) study, we tested whether an OC-resistant avian IAV (H1N1) strain with an H274Y mutation in the neuraminidase (NA-H274Y) could retain resistance while drug pressure was gradually removed. Successively infected mallards were exposed to decreasing levels of OC, and fecal samples were analyzed for the neuraminidase sequence and phenotypic resistance. No reversion to wild-type virus was observed during the experiment, which included 17 days of viral transmission among 10 ducks exposed to OC concentrations below resistance induction levels. We conclude that resistance in avian IAV that is induced by exposure of the natural host to OC can persist in the absence of the drug. Thus, there is a risk that human-pathogenic IAVs that evolve from IAVs circulating among wild birds may contain resistance mutations. An oseltamivir-resistant pandemic IAV would pose a substantial public health threat. Therefore, our observations underscore the need for prudent oseltamivir use, upgraded sewage treatment, and surveillance for resistant IAVs in wild birds.
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| 3. |
- Lundström, Jan O, et al.
(author)
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The geographic distribution of mosquito species in Sweden
- 2013
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In: Journal of the European Mosquito Control Association. - 2054-930X .- 1460-6127. ; 31, s. 21-35
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Journal article (peer-reviewed)abstract
- Surveillance of the actual distribution of mosquito species in Northern Europe is fundamental for evaluating risk for emerging pathogens, and for research on potential vectors. The Swedish mosquito fauna composition and geographic distribution, originally described by Professor Christine Dahl in the 1970´s, included 43 species. We have compiled the information published from 1978 to 2012, and our own surveillance data from 2001 to 2013, and compared this with the species list and geographic distribution provided in "Taxonomy and geographic distribution of Swedish Culicidae" by Dahl (1977). New species detected during these 36 years were Culiseta (Culicella) ochroptera (Peus, 1935) published 1984, Aedes (Aedes) rossicus Dolbeskin, Goritzkaja & Mitrofanova, 1930 published 1986, Anopheles (Anopheles) beklemishevi published 1986, Aedes (Ochlerotatus) euedes (Howard, Dyar & Knab, 1912) published 2001, Aedes (Ochlerotatus) nigrinus (Eckstein, 1918) first recorded in 2012, and Anopheles (Anopheles) algeriensis Theobald, 1903, first recorded in 2013. We provide maps with the distribution by province for each species, including historic information up until 1977, and new records from 1978 to 2013, showing the similarities and differences between the old and the new records. Important findings in recent years include the wide distribution of the Sindbis virus enzootic vector Culex (Culex) torrentium Martinii, 1925, and the more limited distribution of the potential West Nile virus vector Culex (Culex) pipiens Linnaeus, 1758. The updated list of mosquito species in Sweden now includes 49 species.
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| 4. |
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| 5. |
- Dessborn, Lisa, et al.
(author)
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Innate responses of mallard ducklings towards aerial, aquatic and terrestrial predators
- 2012
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In: Behaviour. - Leiden, Netherlands : Brill Academic Publishers. - 0005-7959 .- 1568-539X. ; 149:13-14, s. 1299-1317
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Journal article (peer-reviewed)abstract
- Reproductive success in ducks is strongly influenced by predation on the breeding grounds. Ducklings are targeted by a range of terrestrial, aerial and aquatic predators, giving a strong selective advantage to individuals and broods that have effective ways to avoid predation. In experiments on naive mallard (Anas platyrhynchos) ducklings without an accompanying adult female we investigated the innate ability to identify and avoid threats at varying intensity from aerial, aquatic and terrestrial predators. Ducklings displayed increased vigilance in response to pre-recorded calls of predatory birds, representing a low level of threat. They did not react to visual and olfactory stimuli generated by motionless northern pike (Esox lucius). Neither did they show a strong response to caged American mink (Neovison vison) (visual and olfactory stimuli), although they avoided the area with the mink, indicating a certain level of recognition. High intensity threats were simulated by staging attacks from aerial (goshawk, Accipiter gentilis) and aquatic predators (northern pike). The aerial attack made ducklings dive and scatter under water, whereas the response to attack by pike was to run on the water and scatter in different directions. The lack of response to a 'passive' pike and the rather weak avoidance of mink indicate that olfactory cues are not as important in identifying a potential predatory threat by ducklings as are auditory cues. Visual cues appear to be of little importance unless they are combined with movement, and a clear response is only triggered when the intensity of predator threat is high. Mallard ducklings, thus, show an innate capacity to adjust anti-predator behaviour to different predator types and to threat intensity. Our study highlights the general trade-off between foraging needs and predator avoidance, but also second-order trade-offs in which innate avoidance behaviour towards one type of predator may increase predation risk from another.
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| 6. |
- Dessborn, Lisa, et al.
(author)
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Pike predation affects breeding success and habitat selection of ducks
- 2011
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In: Freshwater Biology. - : Wiley. - 0046-5070 .- 1365-2427. ; 56:3, s. 579-589
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Journal article (peer-reviewed)abstract
- 1. Fish and ducks often belong to the same local food web, and several studies indicate that there is a general negative effect of fish on breeding ducks. This pattern has so far been addressed mainly within the framework of competition for common invertebrate prey, while predation by large fish as a force behind settlement and abundance patterns in ducks remains largely unknown. This is the first study to address the effect of fish predation on breeding ducks, isolated from that of competition, and the first experiment to explore the ability of ducks to identify and avoid lakes with high risk of fish predation.2. We used a before–after control–impact design and 11 naturally fishless lakes. Waterfowl on the lakes were surveyed during the breeding season of 2005. Large adult pike (Esox lucius) were added to two lakes in early spring 2008, and waterfowl surveys were repeated on all 11 lakes.3. Pike introduction did not affect the number of pairs on lakes during the nesting season in any of three focal duck species (mallard Anas platyrhynchos, teal Anas crecca, and goldeneye Bucephala clangula). During the brood-rearing season, however, there was a decrease in duck days in teal and goldeneye in lakes with pike, with similar trends observed in mallard. The number of goldeneye ducklings was also significantly lower in lakes with pike. We were unable to determine whether the response was attributable to direct pike predation or to broods leaving experimental lakes, but in either case, our study demonstrates high fitness costs for ducks breeding on lakes with pike.4. The apparent inability of nesting ducks to detect pike and the clear fitness implications may influence the annual recruitment of ducks on a larger scale as pike are both common and widespread. Vegetation complexity and food abundance are likely to be of overriding importance when breeding ducks are choosing a nesting site. As pike have a strong influence on breeding birds, relying on vegetation and cues of food abundance, while ignoring indicators of predation risk from fish, could lead to lakes with pike acting as an ecological trap.
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| 7. |
- Faraon, Montathar, et al.
(author)
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Learning by coding : A sociocultural approach to teaching web development in higher education
- 2020
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In: Education and Information Technologies. - : Springer Science and Business Media LLC. - 1360-2357 .- 1573-7608. ; 25:3, s. 1759-1783
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Journal article (peer-reviewed)abstract
- As information technology continues to evolve rapidly in society, coding skills become increasingly essential to develop. The purpose of this article is to examine differences between the learner-centered and sociocultural approaches when teaching and learning coding in higher education. A quasi-experiment was applied over six academic semesters evaluating the mentioned approaches in terms of students' explicit attitudes, grades, and course evaluations. The findings indicated that the sociocultural approach may be a viable alternative to the learner-centered approach. More specifically, students indicated a preference for the sociocultural approach over the learner-centered approach, a greater number of students who passed the courses were educated via the sociocultural approach, and overall satisfaction was significantly higher for this approach as well. While the sociocultural approach has demonstrated to be advantageous, its integration in courses must concurrently be carefully balanced against constraints that teachers continuously experience in higher education, such as time and resources, which presents a challenge to the design of courses and to academia at large.
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| 8. |
- Eriksson, Louise, 1973-, et al.
(author)
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Adaptive capacity in the multi-level management system of migratory waterbirds : a case study of participatory goose management in Sweden
- 2024
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In: Journal of Environmental Planning and Management. - : Routledge. - 0964-0568 .- 1360-0559. ; 67:3, s. 522-541
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Journal article (peer-reviewed)abstract
- Adaptive management (AM) is one approach to manage migratory waterbirds, but obstacles to the implementation of AM require adaptive capacities in the management system (rules, institutions, action situations). This study aims to examine the adaptive capacity of participatory goose management in Sweden. Considering the biophysical and institutional context, we analyzed how tangible, individual, and governance assets were associated with technical and social learning. Interviews with informants in the national council for geese, swans, and cranes, and local management groups (LMGs) were conducted, and documentation reviewed. Results revealed evidence of a local preparedness in areas with an LMG. Nevertheless, the study highlighted a need to formalize the evolving system, to consider a more systematic implementation of AM (including regulations allowing for adaptive responses), and to ensure stakeholder acceptance for management tools and visions. The study illustrates the need for a broad set of assets to ensure learning in participatory management.
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| 9. |
- Eriksson, Louise, 1973-, et al.
(author)
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Individuals and Multilevel Management : A Study of the Perceived Adaptive Capacity of the Goose Management System among Farmers in Sweden
- 2022
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In: Society and Natural Resources. - : Informa UK Limited. - 0894-1920 .- 1521-0723. ; 35:1, s. 1-19
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Journal article (peer-reviewed)abstract
- Agricultural damage by geese is a growing problem in Europe and farmers play a key role in the emerging multilevel adaptive management system. This study explored how characteristics associated with the farmer and the farm, along with experience of damage, cognitive appraisals, emotions, and management beliefs were associated with the perceived adaptive capacity of the goose management system among farmers in the south of Sweden (n = 1,067). Survey results revealed that owning a larger farm, a farm closer to water or formally protected areas, along with cultivating cereal and root crops, were associated with geese evoking stronger negative emotions. Further, more previous experience of damage was related to stronger negative emotions and lower levels of perceived adaptive capacity. However, even more important determinants of perceived adaptive capacity were cognitive appraisals, emotions, and management beliefs. Bridging the ties between individual farmers and the system is important for improved multilevel management.
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| 10. |
- Månsson, Johan, et al.
(author)
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Understanding and overcoming obstacles in adaptive management
- 2024
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In: Trends in Ecology and Evolution. - : Elsevier Ltd.. - 0169-5347 .- 1872-8383. ; 38:1, s. 55-71
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Research review (peer-reviewed)abstract
- Adaptive management (AM) is widely promoted to improve management of natural resources, yet its implementation is challenging. We show that obstacles to the implementation of AM are related not only to the AM process per se but also to external factors such as ecosystem properties and governance systems. To overcome obstacles, there is a need to build capacities within the AM process by ensuring adequate resources, management tools, collaboration, and learning. Additionally, building capacities in the legal and institutional frames can enable the necessary flexibility in the governance system. Furthermore, in systems experiencing profound changes in wildlife populations, building such capacities may be even more critical as more flexibility will be needed to cope with increased uncertainty and changed environmental conditions.
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