Ticks, tick-borne microorganisms and infections

• Soleng, Arnulf; Gurung, Deepa; Kjelland, Vivian; Paulsen, Katrine M.; Pedersen, Benedikte Nevjen & Granquist, Erik Georg [Show all 10 contributors for this article] (2026). Microorganisms in Ixodes ricinus ticks in southern and southwestern Norway. International Journal for Parasitology: Parasites and Wildlife. 30. doi: 10.1016/j.ijppaw.2026.101252. Full text in Research Archive Show summary

  Tick-borne diseases constitute a major group of emerging vector-borne infections and represent a growing public health concern in many European countries. In Europe, the most clinically significant agents transmitted by Ixodes ricinus are tick-borne encephalitis virus (TBEV) and Borrelia burgdorferi sensu lato, the causative agents of tick-borne encephalitis and Lyme borreliosis, respectively. Ixodes ricinus also serves as a vector for other pathogenic microorganisms, including louping-ill virus (LIV) and Anaplasma phagocytophilum. Various endosymbionts, such as Wolbachia pipientis and Midichloria mitochondrii, are also found in ticks. In this study, we assessed the prevalence of TBEV, LIV, B. burgdorferi s. l., A. phagocytophilum, W. pipientis, and M. mitochondrii in 3437 I. ricinus ticks collected from five locations in Norway. The estimated pool prevalence of TBEV ranged from 0 to 0.4% in nymphs, while the prevalence in adults ranged from 0 to 7.1%. In contrast, no LIV was detected. Borrelia burgdorferi s. l. was detected at all sites, with prevalences ranging from 3.4% to 14.3% (overall prevalence of 5.7%), representing four genotypes (B. afzelii, B. garinii, B. valaisiana and B. burgdorferi sensu stricto). Estimated pooled prevalence of A. phagocytophilum was 5.1% in nymphs, while the overall prevalence in adults was 19.8%. In adult ticks, W. pipientis and M. mitochondrii occurred at overall prevalences of 11.0% and 84.1%, respectively. In only 12.3% of ticks, none of the agents investigated were detected. However, 32.6% of the ticks showed co-occurrence of infectious agents and/or the endosymbionts. Thus, this underscores the need for improved understanding of microbial interactions influencing tick-borne disease outcomes.

• Kloster, Hanne; Stormo, Camilla; Haaland, Anita Haug; Stuen, Snorre & Kjelland, Vivian (2025). Seroprevalence of IgG Antibodies Against Borrelia burgdorferi Sensu Lato, Anaplasma phagocytophilum, and Tick-Borne Encephalitis (TBE) Virus in Horses in Southern Norway. Microorganisms. 13(4). doi: 10.3390/microorganisms13040771. Full text in Research Archive Show summary

  Ixodes ricinus ticks play a crucial role as carriers of diseases, transmitting pathogens to vertebrate hosts, including horses. This study aimed to investigate the seroprevalence of IgG antibodies against Borrelia burgdorferi sensu lato (s. l.), Anaplasma phagocytophilum, and tick-borne encephalitis virus (TBE-virus) in equine sera collected in southern Norway. In total, sera from 331 horses stabled in four counties (Agder, Vestfold and Telemark, Vestland, and Viken) were analyzed by immunoblot. In total, 66% of the horses were IgG-seropositive for antibodies against one or multiple tick-borne pathogens. The highest seroprevalence was detected against B. burgdorferi s. l. (47%), followed by A. phagocytophilum (34%) and TBE-virus (10%). A significant difference between the counties regarding IgG antibodies against A. phagocytophilum was found, with the highest seroprevalence in horses stabled in the coastal areas of Agder and Vestland. In conclusion, the study demonstrates that horses in southern Norway are at high risk of contracting tick-borne infections.

• Lamsal, Alaka; Edgar, Kristin Skarsfjord; Jenkins, Andrew; Renssen, Hans; Kjær, Lene Jung & Alfsnes, Kristian [Show all 25 contributors for this article] (2023). Prevalence of tick-borne encephalitis virus in questing Ixodes ricinus nymphs in southern Scandinavia and the possible influence of meteorological factors. Zoonoses and Public Health. ISSN 1863-1959. 70(6), p. 473–484. doi: 10.1111/zph.13049. Full text in Research Archive Show summary

  Ixodes ricinus ticks are Scandinavia's main vector for tick-borne encephalitis virus (TBEV), which infects many people annually. The aims of the present study were (i) to obtain information on the TBEV prevalence in host-seeking I. ricinus collected within the Øresund-Kattegat-Skagerrak (ØKS) region, which lies in southern Norway, southern Sweden and Denmark; (ii) to analyse whether there are potential spatial patterns in the TBEV prevalence; and (iii) to understand the relationship between TBEV prevalence and meteorological factors in southern Scandinavia. Tick nymphs were collected in 2016, in southern Scandinavia, and screened for TBEV, using pools of 10 nymphs, with RT real-time PCR, and positive samples were confirmed with pyrosequencing. Spatial autocorrelation and cluster analysis was performed with Global Moran's I and SatScan to test for spatial patterns and potential local clusters of the TBEV pool prevalence at each of the 50 sites. A climatic analysis was made to correlate parameters such as minimum, mean and maximum temperature, relative humidity and saturation deficit with TBEV pool prevalence. The climatic data were acquired from the nearest meteorological stations for 2015 and 2016. This study confirms the presence of TBEV in 12 out of 30 locations in Denmark, where six were from Jutland, three from Zealand and two from Bornholm and Falster counties. In total, five out of nine sites were positive from southern Sweden. TBEV prevalence of 0.7%, 0.5% and 0.5%, in nymphs, was found at three sites along the Oslofjord (two sites) and northern Skåne region (one site), indicating a potential concern for public health. We report an overall estimated TBEV prevalence of 0.1% in questing I. ricinus nymphs in southern Scandinavia with a region-specific prevalence of 0.1% in Denmark, 0.2% in southern Sweden and 0.1% in southeastern Norway. No evidence of a spatial pattern or local clusters was found in the study region. We found a strong correlation between TBEV prevalence in ticks and relative humidity in Sweden and Norway, which might suggest that humidity has a role in maintaining TBEV prevalence in ticks. TBEV is an emerging tick-borne pathogen in southern Scandinavia, and we recommend further studies to understand the TBEV transmission potential with changing climate in Scandinavia.

• Kjelland, Vivian; Stamberg, Paul; Andreassen, Åshild Kristine; Kloster, Hanne; Vikse, Rose & Csango, Peter A. (2021). Borrelia spp. i skogflått samlet fra katter og hunder i Norge. Norsk veterinærtidsskrift. ISSN 0332-5741. 5, p. 284–289. Full text in Research Archive
• Pedersen, Benedikte Nevjen; Jenkins, Andrew & Kjelland, Vivian (2020). Tick-borne pathogens in Ixodes ricinus ticks collected from migratory birds in southern Norway. PLOS ONE. 15(4). doi: 10.1371/journal.pone.0230579. Full text in Research Archive Show summary

  Birds are important hosts for the first life stages of the Ixodes ricinus tick and they can transport their parasites over long distances. The aim of this study was to investigate the prevalence of Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Neoehrlichia mikurensis and Rickettsia helvetica in ticks collected from migratory birds in Norway. A total of 815 Ixodes ricinus ticks from 216 birds trapped at Lista Bird Observatory in southern Norway during spring and autumn migration in 2008 were analysed by real-time PCR. B. burgdorferi s. l. was the most prevalent pathogen, detected in 6.1% of the ticks. The prevalence of N. mikurensis, A. phagocytophilum and R. helvetica was 1.2%, 0.9% and 0.4% respectively. In addition, one sample (0.1%) was positive for B. miyamotoi. In total, 8.2% of the ticks were infected with at least one pathogen. Co-infection with B. burgdorferi s. l. and N. mikurensis or A. phagocytophilum was found in 6.0% of the infected ticks. Our results show that all the known major tick-borne bacterial pathogens in Norway are subject to transport by migratory birds, potentially allowing spread to new areas. Our study showed a surprisingly high number of samples with PCR inhibition (57%). These samples had been extracted using standard methodology (phenol-chloroform extraction). This illustrates the need for inhibition controls to determine true prevalence rates.

• Kjær, Lene Jung; Klitgaard, Kirstine; Soleng, Arnulf; Edgar, Kristin Skarsfjord; Lindstedt, Heidi Elisabeth Heggen & Paulsen, Katrine Mørk [Show all 17 contributors for this article] (2020). Spatial patterns of pathogen prevalence in questing Ixodes ricinus nymphs in southern Scandinavia, 2016. Scientific Reports. 10, p. 1–14. doi: 10.1038/s41598-020-76334-5. Full text in Research Archive
• Kjær, Lene Jung; Klitgaard, Kristine; Soleng, Arnulf; Edgar, Kristin Skarsfjord; Lindstedt, Heidi Elisabeth Heggen & Paulsen, Katrine Mørk [Show all 17 contributors for this article] (2020). Spatial data of Ixodes ricinus instar abundance and nymph pathogen prevalence, Scandinavia, 2016–2017. Scientific Data. 7(1). doi: 10.1038/s41597-020-00579-y. Full text in Research Archive Show summary

  Ticks carry pathogens that can cause disease in both animals and humans, and there is a need to monitor the distribution and abundance of ticks and the pathogens they carry to pinpoint potential high risk areas for tick-borne disease transmission. In a joint Scandinavian study, we measured Ixodes ricinus instar abundance at 159 sites in southern Scandinavia in August-September, 2016, and collected 29,440 tick nymphs at 50 of these sites. We additionally measured abundance at 30 sites in August-September, 2017. We tested the 29,440 tick nymphs in pools of 10 in a Fluidigm real-time PCR chip to screen for 17 different tick-associated pathogens, 2 pathogen groups and 3 tick species. We present data on the geolocation, habitat type and instar abundance of the surveyed sites, as well as presence/absence of each pathogen in all analysed pools from the 50 collection sites and individual prevalence for each site. These data can be used alone or in combination with other data for predictive modelling and mapping of high-risk areas.

• Kjær, Lene Jung; Soleng, Arnulf; Edgar, Kristin Skarsfjord; Lindstedt, Heidi Elisabeth Heggen; Paulsen, Katrine Mørk & Andreassen, Åshild Kristine [Show all 16 contributors for this article] (2019). Predicting the spatial abundance of Ixodes ricinus ticks in southern Scandinavia using environmental and climatic data. Scientific Reports. 9(1). doi: 10.1038/s41598-019-54496-1. Full text in Research Archive Show summary

  Recently, focus on tick-borne diseases has increased as ticks and their pathogens have become widespread and represent a health problem in Europe. Understanding the epidemiology of tick-borne infections requires the ability to predict and map tick abundance. We measured Ixodes ricinus abundance at 159 sites in southern Scandinavia from August-September, 2016. We used field data and environmental variables to develop predictive abundance models using machine learning algorithms, and also tested these models on 2017 data. Larva and nymph abundance models had relatively high predictive power (normalized RMSE from 0.65–0.69, R2 from 0.52–0.58) whereas adult tick models performed poorly (normalized RMSE from 0.94–0.96, R2 from 0.04–0.10). Testing the models on 2017 data produced good results with normalized RMSE values from 0.59–1.13 and R2 from 0.18–0.69. The resulting 2016 maps corresponded well with known tick abundance and distribution in Scandinavia. The models were highly influenced by temperature and vegetation, indicating that climate may be an important driver of I. ricinus distribution and abundance in Scandinavia. Despite varying results, the models predicted abundance in 2017 with high accuracy. The models are a first step towards environmentally driven tick abundance models that can assist in determining risk areas and interpreting human incidence data.

• Jenkins, Andrew; Raasok, Cecilie; Pedersen, Benedikte Nevjen; Jensen, Kristine; Andreassen, Åshild Kristine & Soleng, Arnulf [Show all 12 contributors for this article] (2019). Detection of Candidatus Neoehrlichia mikurensis in Norway up to the northern limit of Ixodes ricinus distribution using a novel real time PCR test targeting the groEL gene. BMC Microbiology. 19. doi: 10.1186/s12866-019-1502-y. Full text in Research Archive Show summary

  Candidatus Neoehrlichia mikurensis is an emerging tick-borne pathogen. It is widely distributed in Ixodes ricinus ticks in Europe, but knowledge of its distribution in Norway, where I. ricinus reaches its northern limit, is limited. In this study we have developed a real time PCR test for Ca. N. mikurensis and used it to investigate the distribution of Ca. N. mikurensis in Norway. Results Real time PCR targeting the groEL gene was developed and shown to be highly sensitive. It was used to detect Ca. N. mikurensis in 1651 I. ricinus nymphs and adults collected from twelve locations in Norway, from the eastern Oslo Fjord in the south to near the Arctic Circle in the north. The overall prevalence was 6.5% and varied locally between 0 and 16%. Prevalence in adults and nymphs was similar, suggesting that ticks acquire Ca. N. mikurensis predominantly during their first blood meal. In addition, 123 larvae were investigated; Ca. N. mikurensis was not found in larvae, suggesting that transovarial transmission is rare or absent. Sequence analysis suggests that a single variant dominates in Norway. Conclusions Ca. N. mikurensis is widespread and common in ticks in Norway and reaches up to their northern limit near the Arctic Circle. Ticks appear to acquire Ca. N. mikurensis during their first blood meal. No evidence for transovarial transmission was found.

• Kjær, Lene Jung; Soleng, Arnulf; Edgar, Kristin Skarsfjord; Lindstedt, Heidi Elisabeth H.; Paulsen, Katrine Mørk & Andreassen, Åshild Kristine [Show all 16 contributors for this article] (2019). Predicting and mapping human risk of exposure to ixodes ricinus nymphs using climatic and environmental data, Denmark, Norway and Sweden, 2016. Eurosurveillance. ISSN 1025-496X. 24(9). doi: 10.2807/1560-7917.ES.2019.24.9.1800101. Full text in Research Archive
• Kjelland, Vivian; Paulsen, Katrine Mørk; Rollum, Rikke; Jenkins, Andrew; Stuen, Snorre & Soleng, Arnulf [Show all 11 contributors for this article] (2018). Tick-borne encephalitis virus, Borrelia burgdorferi sensu lato, Borrelia miyamotoi, Anaplasma phagocytophilum and Candidatus Neoehrlichia mikurensis in Ixodes ricinus ticks collected from recreational islands in southern Norway. Ticks and Tick-borne Diseases. ISSN 1877-959X. 9(5), p. 1098–1102. doi: 10.1016/j.ttbdis.2018.04.005. Full text in Research Archive
• Quarsten, Hanne; Grankvist, Anna; Høyvoll, Liv Ragnhild; Myre, Ingvild Bakken; Skarpaas, Tone & Kjelland, Vivian [Show all 8 contributors for this article] (2017). Candidatus Neoehrlichia mikurensis and Borrelia burgdorferi sensu lato detected in the blood of Norwegian patients with erythema migrans. Ticks and Tick-borne Diseases. ISSN 1877-959X. 8(5), p. 715–720. doi: 10.1016/j.ttbdis.2017.05.004. Full text in Research Archive
• Lager, Malin; Faller, Maximilian; Wilhelmsson, Peter; Kjelland, Vivian; Andreassen, Åshild Kristine & Dargis, Rimtas [Show all 16 contributors for this article] (2017). Molecular detection of Borrelia burgdorferi sensu lato - An analytical comparison of real-time PCR protocols from five different Scandinavian laboratories. PLOS ONE. 12:e0185434(9), p. 1–17. doi: 10.1371/journal.pone.0185434. Full text in Research Archive
• Forselv, Kristine Johanne Nordstrøm; Lorentzen, Åslaug Rudjord; Ljøstad, Unn; Mygland, Åse; Eikeland, Randi & Kjelland, Vivian [Show all 8 contributors for this article] (2017). Does more favourable handling of the cerebrospinal fluid increase the diagnostic sensitivity of Borrelia burgdorferi sensu lato-specific PCR in Lyme neuroborreliosis? Infectious Diseases. ISSN 2374-4235. 50(4), p. 297–302. doi: 10.1080/23744235.2017.1399315. Full text in Research Archive
• Aase, Audun; Hajdusek, Ondrej; Øines, Øivind; Quarsten, Hanne; Wilhelmsson, Peter & Herstad, Tove Karin [Show all 11 contributors for this article] (2016). Validate or falsify: Lessons learned from a microscopy method claimed to be useful for detecting Borrelia and Babesia organisms in human blood. Infectious Diseases. ISSN 2374-4235. 48(6), p. 411–419. doi: 10.3109/23744235.2016.1144931. Full text in Research Archive
• Kjelland, Vivian; Rollum, Rikke; Korslund, Lars; Slettan, Audun & Tveitnes, Dag (2015). Borrelia miyamotoi is widespread in Ixodes ricinus ticks in southern Norway. Ticks and Tick-borne Diseases. ISSN 1877-959X. 6(4), p. 516–521. doi: 10.1016/j.ttbdis.2015.04.004. Full text in Research Archive
• Quarsten, Hanne; Skarpaas, Tone; Fajs, Luka; Noraas, Sølvi & Kjelland, Vivian (2015). Tick-borne bacteria in Ixodes ricinus collected in southern Norway evaluated by a commercial kit and established real-time PCR protocols. Ticks and Tick-borne Diseases. ISSN 1877-959X. 6(4), p. 538–544. doi: 10.1016/j.ttbdis.2015.04.008. Full text in Research Archive
• Haugeberg, Glenn; Hansen, Inger Johanne Widding; Skarpaas, Tone; Noraas, Sølvi & Kjelland, Vivian (2014). Lyme arthritis in Southern Norway - an endemic area for Lyme Borreliosis. BMC Infectious Diseases. 14(1). doi: 10.1186/1471-2334-14-185. Full text in Research Archive Show summary

  Background: Despite Southern Norway is an endemic area for Lyme borreliosis there is a lack of data on Lyme arthritis (LA). In the literature controversies exist if acute LA can develop into chronic arthritis. Our objective was to identify and characterize patients with LA in Southern Norway and explore disease course after antibiotic treatment.Methods: Patients aged 20 years or older with arthritis and a positive serology for Borrelia burgdorferi infection (IgG and/or IgM) suspected of having LA were consecutively recruited either from general practitioners or from hospital departments.Results: From January 2007 to December 2010 a total of 27 patients were assessed. Mean (range) age was 56 years (41-80) and mean symptom duration prior to inclusion was 11.2 weeks (1 day - 2 years). Definite LA was diagnosed in 16 patients, probable LA in 5 patients and 6 patients were concluded to have other arthritis disorders. Among the 21 LA patients 20 had mono-arthritis (knee 18, ankle 2) and 1 had polyarthritis.All LA patients responded favourable to antibiotic treatment and none of the patients developed chronic arthritis after long term follow up, not even in LA patients who had intraarticular glucocorticosteroid (GC) injection prior to antibiotic treatment.Conclusions: Our data shows that LA in Southern Norway is a benign disease which successfully can be treated with antibiotics even in patients treated with GC prior to antibiotics.

• Soleng, Arnulf & Kjelland, Vivian (2013). Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum in Ixodes ricinus ticks in Brønnøysund in northern Norway. Ticks and Tick-borne Diseases. ISSN 1877-959X. 4(3), p. 218–221. doi: 10.1016/j.ttbdis.2012.11.006. Full text in Research Archive

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• Kjelland, Vivian; Korslund, Lars & Slettan, Audun (2014). Fakta om flått. Kagge Forlag AS. ISBN 9788248914143. 126 p. Full text in Research Archive

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• Kjelland, Vivian; Andreassen, Åshild Kristine; Eikeland, Randi; Jenkins, Andrew & Stuen, Snorre (2026). Flåttforskere: Norge er ikke rustet til å håndtere dette flåttscenarioet. Full text in Research Archive Show summary

  Flåtten øker i antall, sprer seg til nye områder, nye flåttarter ankommer landet, og stadig flere mennesker og dyr opplever flåttbitt og sykdom. Samtidig svekkes kunnskapsgrunnlaget vårt. Forskningen på flåtten er ikke bare på et minimum, men er i ferd med å tørke ut.

• Aarøe, Anna; Kjelland, Vivian & Eikeland, Randi (2026). Forsker advarer mot flåttmyter: – Folk må beskytte seg. [Internet]. TV2. Full text in Research Archive Show summary

  Det finnes mange myter om flåtten. Forsker Vivian Kjelland er redd desinformasjonen kan øke smitten av flåttbårne sykdommer.

• Helle, Anette Andersgård; Stuen, Snorre & Kjelland, Vivian (2026). Flått katt, Flått hund | Flått på hund og katt: 4 symptomer du må passe på. Full text in Research Archive Show summary

  Mange firbente bærer på skjult smitte etter flåttbitt. Slik avslører du de usynlige symptomene, og unngår den vanligste miljøfellen når du behandler kjæledyret ditt.

• Kjelland, Vivian (2026). Varsler mye mygg i år: – Perfekte forhold - agderposten.no. [Journal]. Agderposten. Full text in Research Archive Show summary

  Fuktig vårvær og varme har gitt myggen perfekte forhold, og været fremover vil avgjøre hvor ille det kan bli.

• Amundsen, Bård & Kjelland, Vivian (2026). Hvor farlig er flått for hund og katt? [Internet]. Forskning.no. Full text in Research Archive Show summary

  Mange kjæledyr får mye blodsugende flått på seg.

• Grønnevik, Reiulf & Kjelland, Vivian (2026). Beryktet flått påvist i nord – følger utviklingen nøye: – Du kan bli bitt av flått i Finnmark - altaposten.no. [Internet]. Altaposten. Full text in Research Archive Show summary

  Mildere klima gir økt risiko for at flåtten kan etablere seg fast i Finnmark.

• Haaland, Anita Haug; Kloster, Hanne; Stormo, Camilla; Omvik, Katrine; Pétursdóttir, Vala & Mjelde, Hans Kristian [Show all 8 contributors for this article] (2026). Arctic Exposure Pathways: Tick-Borne Pathogens Detected in a Terrestrial Mammal on Svalbard. doi: https:/www.nordtick2026.se/. Full text in Research Archive
• Wehus, Walter Norman & Kjelland, Vivian (2025). Flått: Sørlendingene tar for lett på farene, mens østlendigene er mer bekymret. [Internet]. Forskning.no. Full text in Research Archive Show summary

  En ny europeisk studie viser store kunnskapshull om flått og sykdommene de sprer. Nå kan nye flåttarter være på vei til Norge.

• Kjelland, Vivian (2025). Flere burde vaksinere seg. [Internet]. Sørnett NLA Høgskolen. Full text in Research Archive
• Kloster, Hanne; Nordli, Ine Emilie Olsen; Kjelland, Vivian & Stormo, Camilla (2024). Har årets harde vinter tatt knekken på flåtten? - fvn.no. Full text in Research Archive Show summary

  Årets sørlandsvinter har vært preget av sprengkulde og meterhøy snø. Det er nok mange som ønsker at flåtten har strøket med under disse omstendighetene, men det korte svaret på spørsmålet er: Nei, de fleste flått har nok klart seg helt fint.

• Kjelland, Vivian (2024). Høysesongen er i gang: -Ikke bli kjemperedd. De fleste blir ikke syke. [Journal]. KRS Avisen Kristiansand (https://www.krs.no/). Full text in Research Archive
• Kjelland, Vivian & Kerlefsen, Yvonne (2024). Flåttproblemet øker (kronikk). [Internet]. www.fvn.no. Full text in Research Archive
• Christiansen, Atle; Kjelland, Vivian & Eikeland, Randi (2023). Nå er det høysesong for flåtten. Blodsugeren spiser bare tre ganger i løpet av livet. [Internet]. Forskning.no. Full text in Research Archive
• Kjelland, Vivian & Eikeland, Randi (2023). Nå er det høysesong for flåtten. [Internet]. Universitetet i Agder. Full text in Research Archive
• Kjelland, Vivian (2023). Nå er det høysesong - slik beskytter du deg. [Journal]. Glåmdalen. Full text in Research Archive
• Kjelland, Vivian (2023). Flått og flåttbårne patogener i Norge. Full text in Research Archive
• Kloster, Hanne; Stormo, Camilla; Haaland, Anita Haug; Okstad, Wenche; Andreassen, Åshild Kristine & Stuen, Snorre [Show all 7 contributors for this article] (2022). Seroprevalence of antibodies against Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato and tick-borne encephalitis (TBE) virus in dogs in Norway. Full text in Research Archive
• Jenkins, Andrew; Raasok, Cecilie; Pedersen, Benedikte Nevjen; Jensen, Kristine; Andreassen, Åshild Kristine & Soleng, Arnulf [Show all 12 contributors for this article] (2020). Correction to: Detection of Candidatus Neoehrlichia mikurensis in Norway up to the northern limit of Ixodes ricinus distribution using a novel real time PCR test targeting the groEL gene. BMC Microbiology. 20. doi: 10.1186/s12866-020-1697-y. Full text in Research Archive
• Kjær, Lene Jung; Klitgaard, Kirstine; Soleng, Arnulf; Edgar, Kristin Skarsfjord; Lindstedt, Heidi Elisabeth Heggen & Paulsen, Katrine Mørk [Show all 17 contributors for this article] (2020). Author Correction: Spatial data of Ixodes ricinus instar abundance and nymph pathogen prevalence, Scandinavia, 2016–2017 (Scientific Data, (2020), 7, 1, (238), 10.1038/s41597-020-00579-y). Scientific Data. 7(1). doi: 10.1038/s41597-020-00606-y. Full text in Research Archive
• Kjelland, Vivian (2019). «Dersom du fjerner flått innen 24 timer er det ingen risiko for sykdom» – fleip eller fakta? Full text in Research Archive
• Kjær, Lene Jung; Soleng, Arnulf; Edgar, Kristin Skarsfjord; Lindstedt, Heidi Elisabeth H.; Paulsen, Katrine Mørk & Andreassen, Åshild Kristine [Show all 18 contributors for this article] (2019). A large-scale screening for the taiga tick, Ixodes persulcatus, and the meadow tick, Dermacentor reticulatus, in southern Scandinavia, 2016. Parasites & Vectors. 12:338, p. 1–4. doi: 10.1186/s13071-019-3596-3. Full text in Research Archive
• Kjelland, Vivian (2019). Nei, dette er ikke kaviar, men flått. [Journal]. Agderposten. Full text in Research Archive
• Kjelland, Vivian (2019). Flåtten kan klare seg midt i byen. [Internet]. forskning.no. Full text in Research Archive
• Kjelland, Vivian (2019). Langt flere smittes med flåttsykdommen borreliose enn offentlige tall skulle tilsi. [Internet]. forskning.no. Full text in Research Archive
• Kjelland, Vivian (2019). Her bor flåtten i Skandinavia. [Internet]. Universitetet i Agder. Full text in Research Archive
• Kjelland, Vivian (2019). Flåtten trives godt på Sørlandet. [Journal]. Fædrelandsvennen. Full text in Research Archive
• Kjelland, Vivian (2018). «Dersom du fjerner flått innen 24 timer er det ingen risiko for sykdom» - fleip eller fakta? Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2018). Flått og flåttbårne patogener. Full text in Research Archive
• Kjelland, Vivian; Kjelland, Vivian; Paulsen, Katrine Mørk; Jenkins, Andrew; Stuen, Snorre & Soleng, Arnulf [Show all 9 contributors for this article] (2018). Patogener i skogflått innsamlet fra øyer i Sør-Norge. BestPractice Infeksjon og vaksinasjon. p. 17–21. Full text in Research Archive
• Korslund, Lars & Kjelland, Vivian (2018). Seasonal patterns in questing activity of the sheep tick (Ixodes ricinus) in Scandinavia. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2017). Flått og flåttbårne patogener i Norge. Full text in Research Archive
• Kjelland, Vivian (2017). ScandTick Innovation. Full text in Research Archive
• Kjelland, Vivian; Kjelland, Vivian; Korslund, Lars; Edgar, Kristin Skarsfjord; Stuen, Snorre & Slettan, Audun [Show all 9 contributors for this article] (2017). Ixodes ricinus winter survival and spring emergence in southern Norway. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2017). "Om flåtten" - Epidemiologi og humanpatogene mikrober. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2017). Flått og flåttbårne patogener i Norge. Full text in Research Archive
• Forselv, Kristine Johanne Nordstrøm; Lorentzen, Åslaug Rudjord; Mygland, Åse Daasvand; Ljøstad, Unn; Eikeland, Randi & Kjelland, Vivian [Show all 8 contributors for this article] (2016). Improving diagnostics of Lyme neuroborreliosis – direct molecular detection of Borrelia in blood and cerebrospinal fluid. Full text in Research Archive
• Paulsen, Katrine Mørk; Gurung, D; B, Okbaldet Yohanns; Gibory, Moustafa; Pedersen, Benedikte Nevjen & Vainio, Kirsti [Show all 20 contributors for this article] (2016). Tick-borne diseases in a one health perspective, host and pathogen interplays The search for TBE virus and related pathogens. Full text in Research Archive Show summary

  TBEV (Tick-borne encephalitis virus) and Borrelia burgdorferi sensu lato are among the most important vector-borne diseases that are emerging. They are the main diseases transmitted by Ixodes ricinus ticks in Europe. I. ricinus is known to transmit other pathogenic microorganisms like- louping ill virus, Anaplasma phagocytophilum, and endosymbionts like-Wolbachia pipientis and Midichloria mitochondrii that may have an influence of the pathogenesis in humans and animals. Factors like climate change, human behavior and migrating animals are involved in the distribution of diseases. The main route of disease transmission is through tick bites, but infection through alimentary system for serious infectious agents like TBEV and wild and production animals as sentinels for transmission. The knowledge of natural foci and prevalence of these infectious microorganisms is important for risk assessment of human disease. Preliminary results from 3240 nymph and 234 adult ticks were collected from six location sites of three counties in Norway. The tick samples were analyzed and minimum infection rate/prevalence was calculated. Body fluids of the host animals are valuable epidemiological parameters for TBEV like cow milk and serum from sheep and cows. This study confirms the existence of TBEV endemic foci compared to earlier study. The prevalence of B. burgdorferi s.l., were analyzed in adult ticks while the prevalence of A. phagocytophilum, W. pipientis, M. mitochondrii were studied in nymph and adults. TBEV were detected in a new location in Hordaland county. The detection of TBEV in milk and serum from cows has never been reported in Norway before.

• Paulsen, Katrine Mørk; Rollum, Rikke; Raasok, Cecilie; Gurung, Deepa; Eskeland, Sveinung & Pedersen, Benedikte Nevjen [Show all 17 contributors for this article] (2016). Flåttbårne mikroorganismer i Norge: Ko-infeksjon og ko-lokalisasjon av flåttbårne mikroorganismer. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2016). Flott med flått? Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2016). Hvordan lever egentlig flåtten? Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2015). Prevalence of Borrelia miyamotoi in Norway. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2015). Flåtten - Norges farligste dyr? Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2015). Ticks. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2015). Borrelia. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2015). Farlig flåttbakterie oppdaget i Norge for første gang. [Internet]. www.dagbladet.no. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2015). Ny flått-bakterie oppdaget i Norge. [Internet]. www.uia.no/nyheter. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2015). Ny flåttbakterie i Norge - kan være livsfarlig. [Journal]. Dagbladet. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2014). ScandTick. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2014). Flått og flåttbårne sykdommer i Norge - med resultater fra lokale studier. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2014). Flått og flåttbårne patogener i Norge. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2014). Prevalence of Borrelia miyamotoi in Norway - preliminary results. Full text in Research Archive
• Kjelland, Vivian (2014). Sørlandsflåtten er ikke farligere enn nordlandsflåtten. [Journal]. Aftenposten. Full text in Research Archive
• Soleng, Arnulf & Kjelland, Vivian (2014). Borrelia og Anaplasma i flått fra Brønnøysund i Nordland. BestPractice. 3(4), p. 22–26. Full text in Research Archive
• Kjelland, Vivian & Kjelland, Vivian (2013). Borrelia i Norden. Full text in Research Archive
• Kjelland, Vivian (2013). Flått og flåttbårne sykdommer i Norge. Full text in Research Archive
• Kjelland, Vivian (2013). Ticks and tickborne diseases. Full text in Research Archive
• Kjelland, Vivian (2013). Flått og flåttbårne sykdommer. Full text in Research Archive
• Kjelland, Vivian (2013). Flått-lab. Full text in Research Archive
• Kjelland, Vivian (2013). Flått og flåttbårne sykdommer i Norge. Full text in Research Archive
• Kjelland, Vivian (2013). Flått og flåttbårne sykdommer i Norge. Full text in Research Archive
• Kjelland, Vivian (2013). Flått og flåttbårne sykdommer i Norge. Full text in Research Archive
• Kjelland, Vivian (2013). Presentation of the "Flått dialog" project which aims to improve the communication between the medical community and Lyme borreliosis patient organizations in Norway. Full text in Research Archive
• Kjelland, Vivian & Andreassen, Åshild Kristine (2013). Information about the interregion project on tick-borne diseases; ScandTick. Full text in Research Archive
• Kjelland, Vivian & Andreassen, Åshild Kristine (2013). Presentation of SCANDTICK – an Interreg EU project. Full text in Research Archive
• Kjelland, Vivian & Andreassen, Åshild Kristine (2013). ScandTick – a Nordic collaboration against tick-borne diseases. Full text in Research Archive
• Kjelland, Vivian (2012). Forekomst av sykdomsfremkallende bakterier i flått langs Agder-kysten. Full text in Research Archive
• Kjelland, Vivian (2012). Beiteprosjekt i Agder. Full text in Research Archive
• Kjelland, Vivian (2012). Satser på internasjonalt flått-prosjekt. [Journal]. Fædrelandsvennen. Full text in Research Archive
• Kjelland, Vivian (2012). Flått og flåttbårne sykdommer i Norge. Full text in Research Archive
• Kjelland, Vivian (2012). Flått-stand. Full text in Research Archive
• Kjelland, Vivian (2012). Beiteprosjekt i Agder. Full text in Research Archive
• Kjelland, Vivian (2012). Sopp mot flått. [Journal]. Dagbladet. Full text in Research Archive
• Kjelland, Vivian (2012). Plukket flått av katten midt i januar. [Journal]. Fædrelandsvennen. Full text in Research Archive
• Kjelland, Vivian (2012). Vilt som flåttbærere. [Journal]. Jakt nr.5 2012. Full text in Research Archive
• Kjelland, Vivian (2012). ScandTick. Full text in Research Archive
• Kjelland, Vivian (2012). Flaggar krig mot flått. [Journal]. Forskerforum - tidsskrift for forskerforbundet. Full text in Research Archive
• Kjelland, Vivian (2012). Flått og flåttbårne sykdommer i Norge. Full text in Research Archive
• Andreassen, Åshild Kristine; Kjelland, Vivian; Vainio, Kirsti; Dudman, Susanne Gjeruldsen; Fremstad, Hege Reinertsen & Soleng, Arnulf [Show all 10 contributors for this article] (2015). ScandTick: Kartlegging av analysemetoder for diagnostikk av skogflåttencefalitt (TBE) i ØKS regionen. Folkehelseinstituttet. ISSN 9788280826565. Full text in Research Archive
• Lager, Malin; Kjelland, Vivian; Andreassen, Åshild Kristine; Noraas, Sølvi & Quarsten, Hanne (2015). Jämförelse av realtids-PCR av borrelios som ett komplement till klinisk diagnostik i ÖKS-regionen. Folkehelseinstituttet. ISSN 9788280826695. Full text in Research Archive
• Henningsson, Anna J; Kjelland, Vivian; Andreassen, Åshild Kristine; Noraas, Sølvi & Quarsten, Hanne (2015). Kartläggning av metoder för klinisk diagnostik av borrelios i ÖKS-regionen. Folkehelseinstituttet. ISSN 9788280826688. Full text in Research Archive

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