Tick borne encephalitis (TBE) - Diagnostics, epidemiology and some ongoing studies

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1 Tick borne encephalitis (TBE) - Diagnostics, epidemiology and some ongoing studies Kirsti Vainio, Åshild Andreassen og Susanne G. Dudman National Reference Laboratory for TBE Department of Virology Norwegian Institute of Public Health Reference laboratory diagnostics 1. Detection of TBE virus by cell culture or PCR 1. In-house PCR 2. Sequencing 2. Detection of anti-tbe antibodies 1. Enzygnost ELISA 2. Serion ELISA 3. Euroimmun IIFT 4. RIIFT neutralization test being established 1

2 TBE epidemiology and risk evaluation Several ways to examine the risk of TBE: Describe clinical cases and their geographical localization Detection of virus in ticks by PCR Detection of TBE specific antibodies (serology): Exposed/sick persons and population studies Animal hosts TBE cases infected in Norway (MSIS) Diagnosis year Number Probable place of infection Tromøy Tromøy Lyngdal Mandal Søgne Farsund, Mandal Tromøy, Larvik Tromøy, Lillesand Arendal, Farsund, Flekkefjord, Grimstad, Larvik, Porsgrunn, Risør Tromøy, Arendal, Kr.sand, Mandal Arendal, Farsund, Kr.sand, Lindesnes, Porsgrunn Aust-Agder, Kr.sand, Grimstad, Larvik, Lindesnes, Risør, Sandefjord, Siljan In TBE cases were reported, 2 of which were infected abroad (1 in Sweden and 1 unknown). During TBE cases have been registered in MSIS, of which 81% have been domestic infections. Adults M>K Majority between years of age Annual Report (7) (6) Arendal, Froland, Larvik, Lillesand, Mandal, Porsgrunn, Sarpsborg, Skien Arendal, Farsund, Larvik, Lillesand, Porsgrunn (1 Germany) Arendal, Iveland, Larvik, Lillesand (1 in Sverige, 1 unknown) 2

3 TBE cases reported in MSIS with presumed place of infection in Norway TBE and LIV seroprevalence in cervids from Farsund and Molde In collaboration with The Norwegian Veterinary Institute we investigated 118 sera from cervids for TBE IgG. LIV IgG was done on all sera by the reference lab in Scotland Sera collected in 2005 TBE seroprevalence 31 % of deers and 56% of mooses in Farsund, whereas only one deer was positive with TBE NT in Molde LIV in Farsund: 3 of 23 roe deer verified, 2 of 4 red deer and 3 of 23 moose. No LIV positives in Molde Tick-borne encephalitis virus and louping-ill virus may co-circulate in Southern Norway. Ytrehus B, Vainio K, Dudman SG, Gilray J, Willoughby K. Vector Borne Zoonotic Dis Oct;13(10): doi: /vbz Epub 2013 Jun 29. 3

4 TBE Østfold 461 blood donors living in Østfold county enrolled in the study. Serum anti-tbe IgG detected by ELISA and positive sera confirmed by TBE NT. All participants filled out a questionnaire regarding tick exposure, outdoor activities, flavivirus vaccination/infection. 6 were TBE IgG positive and 5 of them were confirmed by NT. 2 TBE vaccinated. 3 unvaccinated positives = 0,65% May 2012: 740 ticks collected at Spjærøy: 0,14% TBE PCR positive Larsen,Kanestrøm,Bjørland,Andreassen,Soleng,Vene, Dudman. Detection of specific IgG antibodies in blood donors and Tick-borne encephalitis virus in ticks within a non-endemic area in South-East Norway. Scandinavian Journal of Infectious Diseases, 2014 Assessment of the Norwegian population s knowledge, attitudes and sources of information regarding ticks and tick-borne diseases Emily MacDonald, Solveig Myking and Line Vold Aim of the study: To assess knowledge, attitudes, practices, sources of information and media portrayal of ticks and tick-borne diseases in Norway In order to improve information provided by Norwegian Institute of Public Health (NIPH). Two parts conducted in 2013: 1) Nationwide survey (cross-sectional study): Sample of 1500 from the National population register (Adults over 18 years) 2) Content analysis of newspaper articles 4

5 Scandinavian Cooperation Department of Economics, University of Gothenburg in the PhD project by Daniel Slynge Comparing questionnaires Developed core questions that can be directly compared Focus differs slightly The questionnaire: Categories of questions: Knowledge of ticks/tick-borne diseases Exposure to ticks/tick-borne diseases Risk perception Outdoor activities Protective behaviours Vaccination Information sources Demographics (inc. education, income) 5

6 Sources of information This study received financial support from EU through Interreg IV A to ScandTick (project ID ) 6