Symposia

S1. DIVERSITY OF SYMBIOTIC INTERACTIONS IN TICKS

Organizers: Yuval Gottlieb (University of Jerusalem, Israel) and Olivier Duron (CNRS, France)

Short description: Ticks recently were shown to harbour high numbers of endosymbionts: at least 10 distinct genera of maternally inherited bacteria have been reported in ticks over the last decade. Among them, Coxiella-like endosymbionts and Francisella-like endosymbionts have been identified as obligate symbionts required for tick survival and reproduction. However, the effects of symbionts (eg. Spiroplasma ixodetis, Midichloria, Cardinium, Rickettsiella, and others) are poorly known in most cases although they are likely to influence tick's biology. With recent data obtained in various and different tick species, we believe it is timely to get together and discuss to better understand the path of symbiont interactions with ticks. The symposium may also include time for guided discussion in which we will discuss the similarities in the various systems found in ticks and ways for future collaborations and the theme promotion.

 

S2. TICKS AND TICK-BORNE DISEASES OF SOUTHEAST ASIA

Organizer: Trevor Petney (State Museum of Natural History Karlsruhe, Germany / Khon Kaen University, Thailand)

Short description: Knowledge of the tick fauna of Southeast Asia is either patchy or, in some cases, for example Cambodia and Myanmar, poor. Nevertheless, 97 species have been recorded from continental Southeast Asia alone, to which must be added a large number of endemic species from the island states, making it one of the most diverse regions for ticks worldwide. Not only is information of the species of ticks present limited, but throughout Southeast Asia, work on the tick-borne diseases of stock and companion animals, as well as of humans, is in its infancy, and the medical, veterinary and socio-economic importance of these diseases is largely unknown. In this section our aim is to consolidate our knowledge of ticks and tick-borne diseases in Southeast Asia.

 

S3. TICK VECTOR COMPETENCE: CHALLENGES FOR THE FUTURE

Organizer: Olaf Kahl (Tick-radar GmbH, Germany) and Nathalie Boulanger (University of Strasbourg, France)

Short description: New microorganisms have been identified in rapidly growing numbers in ticks worldwide, often only by DNA/RNA fragments. The question is whether they can be transmitted by ticks to vertebrate hosts. The answer to that question has major consequences on the handling of those ticks and has to be given for each combination of tick species and microorganism separately. Molecular biology is a powerful tool to detect genetic material of microorganisms, but it can usually not define the vector status of carrier ticks. Vector competence studies usually need transmission experiments (i) to get an impression of the natural transmission cycle of a given microorganism and (ii) to evaluate its pathogenic potential. In this session, we will define the different actors needed to maintain the circulation of a pathogen in a natural focus and illustrate the different pitfalls in vector research. We will also discuss how to identify vector ticks of microorganisms.

 

S4. TICK-HOST-PATHOGEN INTERACTIONS: GETTING CLOSER TO DISEASE PREVENTION AND CONTROL

Organizer: Jose de La Fuente (Instituto de Investigación en Recursos Cinegéticos, Spain)

Short description: Tick-borne diseases (TBDs) represent a growing burden for human and animal health worldwide. Several approaches including the use of chemicals with repellency and parasiticidal activity, habitat management, genetic selection of hosts with higher resistance to ticks, and vaccines have been implemented for reducing the risk of TBDs. However, the application of latest gene editing technologies in combination with vaccines likely combining tick and pathogen derived antigens and other control measures would result in the development of effective, safe, and environmentally sound integrated control programs for the prevention and control of TBDs. This approach in combination with latest omics technologies and focusing on biological processes involved in tick-host, tick-pathogen and host-pathogen interactions would allow the identification and combination of tick-derived and pathogen-derived protective antigens affecting tick infestations, tick pathogen infection and transmission, tick attachment and feeding, and/or host pathogen infection.

 

S5. TICK VACCINES: ANTIGEN DISCOVERY AND EVALUATION OF EFFICACY

Organizer: Theo Schetters (University of Pretoria, South Africa)

Short description: The control of tick infestation is paramount for the livelihood of rural communities that depend on small scale farming. One of the control measures (in addition to the use of acaricides) is vaccination. The first recombinant vaccines that were commercialized were based on the protective activity of Bm86, a protein from the midgut of Rhipicephalus microplus ticks. Because these vaccines did not completely prevent tick infestation, unlike acaricides when these were first introduced, vaccination has not been widely adopted. These results have stimulated research to develop vaccines with an improved efficacy profile. Moreover, there is a clear need for experimental models that can be used to screen vaccine candidates. In this session, the aim is to bring together the presentation of new candidate vaccine antigens, and discuss the different in vivo and in vitro models that are used to determine vaccine efficacy.

 

S6. THE IXODES 1000+ GENOMES CONSORTIUM (IX1000+G): ENABLING DATA-DRIVEN SOLUTIONS TO TICK-BORNE DISEASES

Organizers: Catherine A. Hill (Purdue University, USA) and Jose de la Fuente (Instituto de Investigación en Recursos Cinegéticos, Spain)

Short description: Diseases transmitted by hard ticks (Acari; Ixodidae) represent serious threats to global biosecurity, public health and food security. Human-tick encounters resulting in pathogen transmission are increasing around the world, fuelling the need for new strategies to prevent infectious bites and control tick-borne diseases (TBDs). The Ixodes 1000+ Genomes (Ix1000+G) project aims to sequence representatives of the global population of Ixodes ticks – a genus that is notorious worldwide for its impact on human and animal health and transmission of multiple pathogens including causative agents of Lyme borreliosis, anaplasmosis, babesiosis and tick-borne encephalitis. The vision is to facilitate data-driven solutions – novel diagnostics, therapeutics and tick control technologies - to fight TBDs. The initiative hopes to build multiple reference assemblies to support research on Ixodes spp. in North America, Europe, Africa and the Asia-Pacific, and catalogue natural genetic variation among wild populations of Ixodes and their microbial assemblies. This symposium will present genome-centric research goals and priorities, progress towards genomic tools and resources, and highlight community research on Ixodes population genetics and evolutionary biology, microbiome structure and the systems biology of tick-host-pathogen interactions. Additional goals are to build communities and partnerships, and expand efforts for major and minor vector species representing evolutionarily diverse members of the Ixodidae.

 

S7. TICK-BORNE ENCEPHALITIS

Organizers: Lidia Chiţimia-Dobler and Gerhard Dobler (Bundeswehr Institute of Microbiology, Munich, Germany)

Short description: Tick-borne encephalitis (TBE) is the most important medical tick-borne viral disease in Eurasia. There is increasing evidence that TBE also plays a role for some species of animals. Even though substantial underreporting is likely, more than 10.000 human cases are reported annually. In addition, TBE emerges in areas previously believed to be free of the disease posing an increasing risk of infection to humans and animals. Recently, generated data on the epidemiology of TBE, the pathogenesis, and immune responses to infection and on vaccination quested previous concepts and need to be discussed again. The symposium will summarize the new data and concepts regarding the ecology, epidemiology, virology, diagnostics, prevention and treatment of TBE.

 

S8. RETHINKING OUR APPROACH TO UNDERSTANDING TICK-BORNE HEMORRHAGIC FEVER VIRUSES: WHY WE NEED A TRANSDISCIPLINARY APPROACH

Organizer: Dennis Bente (Galveston National Laboratory, University of Texas Medical Branch,  Galveston, Texas, USA)

Short description: Over the last decades, tick-borne hemorrhagic fever viruses such as Crimean-Congo hemorrhagic fever virus and their tick vectors have increased in prevalence around the world and new tick-borne viruses have emerged recently. Little is known about the tick-virus-host dynamics, and much of our knowledge is derived from other tick-borne pathogens. Research with these viruses is typically limited to high or maximum containment facilities and is focused on molecular aspects of the viruses rather than tick biology, tick-host interactions, and ecology. This symposium will identify and prioritize knowledge gaps in tick-borne virus research and seek to foster transdisciplinary collaborations.