GERI 2015 Genes, Ecosystems and Risk of Infection 21-23 April 2015 Aquila Atlantis Hotel, Heraklion, Crete, Greece GERI 2015 Genes, Ecosystems and Risk of Infection 21-23 April 2015 Aquila Atlantis Hotel, Heraklion, Crete, Greece > Abstracts Oral presentations Session 1 Genes Mosquito-borne viruses in south Moravia (Czechland) - summary of an EDENext study Hubalek Zdenek 1*, Rudolf Ivo 1, Sebesta Oldrich 1, Betasova Lenka 1, Blazejova Hana 1, Sikutova Silvie 1, Venclikova Kristyna 1, 2, Strakova Petra 1, 2, Jedlickova Petra 1 1 : Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic (IVB) Brno 2 : Masaryk University, Department of Experimental Biology, Brno (MU) Kotlarska 2 611 37 Brno * : Corresponding author In the years 2011-2014, we examined 51,440 female mosquitoes (in 1,024 pools; 50,496 Culex modestus, 944 Cx. pipiens) inhabiting reed-belts of south-Moravian fishponds. While Sindbis alphavirus RNA was not detected in the mosquitoes, RNA of West Nile flavivirus lineage 2 (WNV-2) was found in 13 pools of Cx. modestus caught in 2013. From five of these positive pools, WNV-2 was additionally isolated on suckling mice (SM). One pool of Cx. modestus contained RNA of Usutu flavivirus (USUV), but the isolation attempt on SM was unsuccessful. Using SM inoculated intracerebrally, we examined 8,100 Anopheles hyrcanus (in 114 pools) collected in the same habitats, 3,132 Cx. modestus (62 pools), 550 Cx. pipiens (10 pools) and 41 Uranotaenia unguiculata (2 pools). Two strains of Tahyna orthobunyavirus (California encephalitis group) were isolated from An. hyrcanus collected in 2013. A total of 740 male Cx. pipiens (in 16 pools) were examined by RT-PCR, but no flavivirus RNA was found in them. No flavivirus RNA was detected in 14,986 female Cx. pipiens (305 pools), 282 Culiseta annulata (8 pools) and 42 Anopheles maculipennis group (4 pools), overwintering in cellars in south Moravia during four winters from 2011 to 2014. Serosurvey (plaque-reduction neutralization test) of 146 common coots (Fulica atra) for WNV and USUV in 2011 revealed 18 birds reacting against WNV. The WNV seropositive samples were then titrated in parallel for antibodies against tick- borne encephalitis virus, WNV and USUV to exclude cross-reactivity. Two birds (1.4%) had the highest titers of antibodies against WNV and nine birds (6.2%) were specifically seropositive for USUV, while in seven birds the infecting flavivirus could not be differentiated. Our results indicate that WNV and USUV infections co-occur in common coots examined in Moravia, the USUV infection being more common. We autopsied nine birds found dead in south Moravia in the years 2011 and 2012: four blackbirds (Turdus merula), two sparrowhawks (Accipiter nisus), two sakers (Falco cherrug) and one kestrel (Falco tinnunculus), and carried out virus isolation attempts from their internal organs. Usutu virus killed two blackbirds. Mosquito-borne West Nile, Usutu and Tahyna viruses occur in south Moravia recently. 2 May complete genome-based distances be of help for taxonomical classification of members of the genus Phlebovirus within the Bunyaviridae family ? Alkan Cigdem 1*, Bichaud Laurence 1*, Alten Bulent 2*, Ozbel Yusuf 3*, Volf Petr 4*, Moin Vaziri Vahideh 5*, Zhioua Elyes 6*, Izri Arezki 1*, Charrel Remi 1* 1 : UMR190 "Emergence des Pathologies Virales" (Aix-Marseille Univ. ? IRD French Institute of Research for Development ? EHESP French School of Public Health, Marseille, France) AixMarseille Univ 2 : Hacettepe University (HU-ESRL) Faculty of Science, Department of Biology, ESRL Laboratories, Beytepe-Ankara www.hacettepe.edu.tr 3 : Ege University Medical Faculty, Department of Parasitology, Izmir, Turkey 4 : Department of Parasitology, Charles University, Prague 5 : Department of Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences 6 : Institut Pasteur de Tunis (IPT) 13 Place Pasteur BP 74 1002 Tunis www.pasteur.tn * : Corresponding author The Bunyaviridae family is constituted of 5 genera. Species demarcation is difficult and has been defined by serological criteria (such as cross-neutralisation and cross-hemagglutination- inhibition tests). For 3 genera (Orthobunyavirus [OBV], Hantavirus [HV] and Tospovirus[TV]), genetic distances (AA sequences of nucleoprotein (N) are one of the criteria that is taken into account for classification into species; for HV, glycoprotein sequences are also considered). Due to the lack of sequence data until recently, there is no cut-off value defined for species demarcation among the members of the Nairovirus [NV] and Phlebovirus [PhV] genera. For the latter, species are defined by the serological relationships, and are distinguishable by four-fold differences in two-way neutralization tests It is obvious that supplementary criteria would help species demarcation within the genus Phlebovirus , and that sequence data that have been massively produced in the last 4 years are promising candidate to achieve polythetic species definition. In this study we compiled all complete AA sequences available that are presented as: number (nb) of genbank sequences / nb of new sequences (determined by our group) / total nb of sequences analysed / nb of pairs of distances used for calculations: For N (87/10/97/4657), Ns (80/11/91/4096), Gn (62/12/74/2702), Gc (62/12/74/2702), and L (60/11/71/2485) complete AA sequences were used for studying the distribution of amino acid evolutionary distances for each of the 5 genes, independently. Intra- and interspecies cut-off values were calculated using 3 different sets of data: (i) set#1 was species recognized by ICTV, (ii) set#2 was set#1+tentative species listed by ICTV, (iii) set#3 was set#1&2+newly discovered viruses not yet listed by ICTV. N sequences allowed to discriminate intra-species from inter-species whereas Gn, Gc and L sequences allowed to discriminate intra-species, interspecies excluding tick-borne viruses, and tick-borne viruses against mosquito-borne and sandfly-borne viruses. Ns sequences were not suitable. Possible cut-off values were determined and accordingly we propose (i) to create a tick-borne clade within the genus Phlebovirus, (ii) to revisit the putative classification proposed by Palacios et al for newly sequenced phleboviruses, and (iii) to modify the cut-off values proposed in 2009 based on limited number of complete sequences. 3 Transcriptomic studies of Ixodes ricinus salivary glands lead to the identification of vaccine candidates against tick and tick-borne pathogens Simo Ladislav 1, Bonnet Sarah 1* 1 : USC INRA Bartonella-ticks, UMR BIPAR ENVA-ANSES Institut national de la recherche agronomique (INRA) * : Corresponding author Ixodes ricinus, the most widespread and abundant tick in Europe, frequently bites humans and is the vector of several pathogens including: viruses, parasites, and bacteria. It has been reported that the transmission of tick-borne pathogens is directly linked to tick saliva which contains key components underlining this action. Ultimately, tick salivary secreted molecules facilitate pathogen transmission by modulation of inflammatory, immune, and haemostatic processes at the tick-host interface. One of the promising approaches for the prevention of tick-borne pathogen transfer includes the development of vaccine strategies targeting conserved sialome components of ticks that play key roles in vector infestation and/or vectorial capacity. To identify such components, we identify some differentially expressed transcripts in I. ricinus salivary gland (SG) based on pathogens infection. We used next generation sequencing techniques to compare gene expression profiles of Bartonella henselae-infected and non-infected I. ricinus females SG. Among 24,539 isotigs identified, 829 and 517 transcripts were either significantly up- or down regulated respectively, in response to tick bacterial infection. Currently, our attention is paid mainly to secreted proteins which have shown to be up-regulated during the infection of the tick. Among them, the most up-regulated transcript encoding BPTI/Kunitz family serine protease inhibitor (IrSPI) has been studied in depth. RNA interference of IrSPI in Ixodes females affected both feeding and bacteria transmission. Temporal and spatial expression pattern of IrSPI has been examined using qRT-PCR and tissue specific RT-PCR followed by in situ hybridisation. Immunization of mammal's models with the recombinant IrSPI is currently ongoing in our laboratory. Mining the I. ricinus salivary gland transcriptome is shedding light onto molecular interactions between ticks and tick-borne pathogens. As well as tick feeding biology, which may ultimately lead to uncovering novel vaccine candidates for tick control. 4 Using population genetics to assess tick dispersal, from the mainland to the landscape scale : a review of current knowledge and its utility to design tick-control methods Plantard Olivier 1, Quillery Elsa 1, 2, Collini Margherita 3 ,4, Panziera Alex 5, Trucchi Emiliano 6, Rizzoli Annapaola 3, Hauffe Heidi C. 3 1 : UMR 1300 INRA/ONIRIS Bioagression, Epidémiologie et Analyse de Risques (BIOEPAR) INRAOniris Ecole Nationale Vétérinaire, Agroalimentaire et de l'Alimentation, Nantes-Atlantique, Atlanpole - La Chantrerie B.P. 40706, F- 44307 Nantes cedex 03, France http://www6.angers-nantes.inra.fr/bioepar 2 : Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Chemical Ecology Unit, Box 102, 230 53 Alnarp, Sweden http://www.slu.se/en/departments/plant-protection-biology/