0000000000033767
AUTHOR
Tarja Sironen
showing 24 related works from this author
The impact of wildlife and environmental factors on hantavirus infection in the host and its translation into human risk
2023
Identifying factors that drive infection dynamics in reservoir host populations is essential in understanding human risk from wildlife-originated zoonoses. We studied zoonotic Puumala orthohantavirus (PUUV) in the host, the bank vole ( Myodes glareolus ), populations in relation to the host population, rodent and predator community and environment-related factors and whether these processes are translated into human infection incidence. We used 5-year rodent trapping and bank vole PUUV serology data collected from 30 sites located in 24 municipalities in Finland. We found that PUUV seroprevalence in the host was negatively associated with the abundance of red foxes, but this process did no…
Molecular detection of Bartonella spp. in deer ked pupae, adult keds and moose blood in Finland
2014
SUMMARYThe deer ked (Lipoptena cervi) is a haematophagous ectoparasite of cervids that harbours haemotrophic Bartonella. A prerequisite for the vector competence of the deer ked is the vertical transmission of the pathogen from the mother to its progeny and transstadial transmission from pupa to winged adult. We screened 1154 pupae and 59 pools of winged adult deer keds from different areas in Finland for Bartonella DNA using PCR. Altogether 13 pupa samples and one winged adult deer ked were positive for the presence of Bartonella DNA. The amplified sequences were closely related to either B. schoenbuchensis or B. bovis. The same lineages were identified in eight blood samples collected fro…
Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
AbstractBackgroundTicks are responsible for transmitting several notable pathogens worldwide. Finland lies in a zone where two human-biting tick species co-occur:IxodesricinusandIxodespersulcatus. Tick densities have increased in boreal regions worldwide during past decades, and tick-borne pathogens have been identified as one of the major threats to public health in the face of climate change.MethodsWe used species distribution modelling techniques to predict the distributions ofI.ricinusandI.persulcatus,using aggregated historical data from 2014 to 2020 and new tick occurrence data from 2021. By aiming to fill the gaps in tick occurrence data, we created a new sampling strategy across Fin…
Quasispecies dynamics and fixation of a synonymous mutation in hantavirus transmission.
2008
RNA-dependent RNA polymerases, the key enzymes in replication of RNA viruses, have a low fidelity; thus, these viruses replicate as a swarm of mutants termed viral quasispecies. Constant generation of new mutations allows RNA viruses to adapt swiftly to a novel environment through selection of both pre-existing and de novo-generated genetic variants. Here, quasispecies dynamics were studied in vivo in controlled hantavirus transmission from experimentally infected to naïve rodents through infested cage bedding. An elementary step of virus microevolution was apparent, as one synonymous mutation (A759G) repeatedly became fixed in the viral RNA quasispecies populations in the recipient animals.
Experimental investigation of a hantavirus host-switch between arvicoline rodents Lemmus lemmus and Myodes glareolus
2014
Serological Survey of Rodent-Borne Viruses in Finnish Field Voles
2014
In northern Europe, rodent populations display cyclic density fluctuations, which can be correlated with the human incidence of zoonotic diseases they spread. During density peaks, field voles (Microtus agrestis) become one of the most abundant rodent species in northern Europe, yet little is known of the viruses they host. We screened 709 field voles, trapped from 14 sites over three years, for antibodies against four rodent-borne, potentially zoonotic viruses or virus groups: hantaviruses, lymphocytic choriomeningitis virus (LCMV), Ljungan virus (LV) and orthopoxviruses (OPV). Antibodies against all four viruses were detected. However, seroprevalence of hantaviruses, LV and LCMV was low. …
Food limitation constrains host immune responses to nematode infections.
2016
Trade-offs in the allocation of finite-energy resources among immunological defences and other physiological processes are believed to influence infection risk and disease severity in food-limited wildlife populations. However, this prediction has received little experimental investigation. Here we test the hypothesis that food limitation impairs the ability of wild field voles ( Microtus agrestis ) to mount an immune response against parasite infections. We conducted a replicated experiment on vole populations maintained in large outdoor enclosures during boreal winter, using food supplementation and anthelmintic treatment of intestinal nematodes. Innate immune responses against intestina…
Additional file 7 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 7: Figure S6. Partial dependency plots for (a) I. ricinus and (b) I. persulcatus solely based on host data.
Supporting information for The impact of wildlife and environmental factors on hantavirus infection in host and its translation into human risk
2023
It contains describtive plot for data, supplementary methods and results
Additional file 3 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 3: Figure S3. The range (lines) and mean (dots) of model performances over 50 model runs in each model algorithm estimating habitat suitabilities for I. persulcatus in different variable compositions: (a) environmental only, (b) host only, (c) environmental and host, and (d) environmental, host, and suitability for I. ricinus.
Additional file 4 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 4: Figure S4. The relative contributions of the explanatory variables in the data set of (a) host only, (b) environment only based on the mean ensemble model.
Additional file 8 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 8: Figure S7. Partial dependency plots for (a) I. ricinus and (b) I. persulcatus based on combined host and environmental data, and habitat suitability data for the other tick species.
Additional file 3 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 3: Figure S3. The range (lines) and mean (dots) of model performances over 50 model runs in each model algorithm estimating habitat suitabilities for I. persulcatus in different variable compositions: (a) environmental only, (b) host only, (c) environmental and host, and (d) environmental, host, and suitability for I. ricinus.
Additional file 6 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 6: Figure S5. Partial dependency plots for (a) I. ricinus and (b) I. persulcatus solely based on environmental data.
Additional file 5 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 5: Table S1. The number of times each model contributed to the final ensemble in different data sets.
Description of research methods and results tables from Food limitation constrains host immune responses to nematode infections
2016
Trade-offs in the allocation of finite-energy resources among immunological defences and other physiological processes are believed to influence infection risk and disease severity in food-limited wildlife populations. However, this prediction has received little experimental investigation. Here we test the hypothesis that food limitation impairs the ability of wild field voles (Microtus agrestis) to mount an immune response against parasite infections. We conducted a replicated experiment on vole populations maintained in large outdoor enclosures during boreal winter, using food supplementation and anthelmintic treatment of intestinal nematodes. Innate immune responses against intestinal p…
Additional file 2 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 2: Figure S2. The range (lines) and mean (dots) of model performances over 50 model runs in each model algorithm estimating habitat suitabilities for I. ricinus in different variable compositions: (a) environmental only, (b) host only, (c) environmental and host, and (d) environmental, host, and suitability for I. ricinus.
Additional file 7 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 7: Figure S6. Partial dependency plots for (a) I. ricinus and (b) I. persulcatus solely based on host data.
Additional file 1 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 1: Figure S1. (a) The sampling strategy for new collections in 2021 was created based on the following criteria. Subdivisions of landscape areas (Area1–Area4), CORINE land cover 2018, a 5-km buffer around existing I. persulcatus occurrences (grey circles), and a 500-m buffer around roads were used to delimit the four sampling areas (light grey lines). For each sampling area, a random sample of 25 collection locations was created depending on the relative shares of forest and meadow categories in each area. (b) The map showing the 2021 results indicates the locations where I. ricinus was found with B. burgdorferi (s.l.)-positive locations.
Additional file 4 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 4: Figure S4. The relative contributions of the explanatory variables in the data set of (a) host only, (b) environment only based on the mean ensemble model.
Additional file 5 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 5: Table S1. The number of times each model contributed to the final ensemble in different data sets.
Additional file 8 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 8: Figure S7. Partial dependency plots for (a) I. ricinus and (b) I. persulcatus based on combined host and environmental data, and habitat suitability data for the other tick species.
Additional file 6 of Predicting habitat suitability for Ixodes ricinus and Ixodes persulcatus ticks in Finland
2022
Additional file 6: Figure S5. Partial dependency plots for (a) I. ricinus and (b) I. persulcatus solely based on environmental data.
Data from: Food limitation constrains host immune responses to nematode infections
2016
Trade-offs in the allocation of finite-energy resources among immunological defences and other physiological processes are believed to influence infection risk and disease severity in food-limited wildlife populations. However, this prediction has received little experimental investigation. Here we test the hypothesis that food limitation impairs the ability of wild field voles (Microtus agrestis) to mount an immune response against parasite infections. We conducted a replicated experiment on vole populations maintained in large outdoor enclosures during boreal winter, using food supplementation and anthelmintic treatment of intestinal nematodes. Innate immune responses against intestinal p…