Prominent scientists worldwide have already accepted to act as keynote speakers or plenary speakers. Plenary speakers are those who provide a plenary talk during the plenary sessions at TTP10. Keynote speakers are those who provide a keynote lecture during the parallel sessions (including those sections organized as “Symposia”) at TTP10.

 

PLENARY SPEAKERS

 

Agustín Estrada-Peña University of Zaragoza, Zaragoza, Spain Agustín Estrada-Peña (born 1959) is Professor of Zoonoses in the Faculty of Veterinary Medicine, Zaragoza (Spain). His work is devoted to capture the finely tuned ecological relationships between ticks, environment, hosts and pathogens, using diverse methods: from satellite images recording environmental conditions, to the study of the rewiring of the molecular machinery of ticks shaped by pathogens. His goals are the incorporation of mathematical tools commonly used in other fields into the description of the ecology and epidemiology of ticks. He is deeply concerned with the climate trends and the human modifications of the habitat, impacting the circulation of tick-transmitted pathogens. He is currently serving as Subject Editor in two journals and is co-author or co-editor of scientific papers and books, with an h-index of about 60. The many scales of the tick-borne pathogens relationships: an epidemiological tale In the several years that happen since the concept of “One Health” was built, few studies have been devoted to the integral application of the concept to the tick-borne pathogens affecting human health. In the last decades, we assisted to the development of powerful sequencing methods that are raising a deeper knowledge on these pathogens. We also improved our knowledge about tick-host relationships (i.e., main hosts of each species of tick) in orders of magnitude. Information about the geographical distribution of wild hosts is massively available, as are databases containing details on morphological and physiological traits of vertebrates. Finally, weather data for large regions are routinely captured by a cloud of earth-orbiting satellites, at a resolution unexpected only a few years ago. A change of paradigm seems to be necessary if we aim to integrate all these data into a unifying framework. The main purpose is the proposal for implementing an agenda for research. That agenda is specifically focused on the preparation of our society for the impact, adaptation, and resilience. It must to be supported by the concepts of the One Health approach, with a background of climate change and considering the contributions of both livestock and wildlife in the circulation of tick-borne pathogens. In this presentation I would like to introduce different methods of integration of these data into an approach implementing different perspectives. Even if we continue capturing the intricate processes of these pathogens at the local or regional scales (the foundations over which that agenda for research must be erected), it seems unnecessary to continue promoting alternatives of control at that scale: a large area approach is an essential part of a new paradigm. The relationships between climate, human habits, livestock management and niche overlap of ticks with the wildlife could be understood and translated to diverse strategies of control at large scales. This is the scale at which major webs of interacting organisms are studied: the proposed agenda must take our current knowledge one step forward. This is also the purpose of the One health concept: the integration of approaches from different fields into a unique frame of reference.

Kelly A. Brayton Washington State University, USA Dr. Kelly Brayton holds a PhD from Purdue University and did post-doctoral work at the Onderstepoort Veterinary Institute in South Africa.  After moving to Washington State University Dr. Kelly Brayton provided the first genome sequence for several pathogens of veterinary importance, with a primary focus on Anaplasma species.  Her interest is in elucidating the pathogen-vector interface and she has taken several approaches to study this relationship including comparative genomics, examining interactions of the tick microbiome on pathogen acquisition, and the role of type 4 secretion system effectors at the tick interface.  Professor Kelly Brayton is the Treasurer for the Society for Tropical Veterinary Medicine, Past-President of the American Society for Rickettsiology, and a Fellow of the American Association for the Advancement of Science. The genus Anaplasma: comparative to functional genomics Although tick transmitted pathogens of the genus Anaplasma have been known for over a century, the obligate intracellular nature of these organisms has impeded progress in elucidating their biology and developing vaccines.    Undoubtedly a genome sequence is a necessity to begin to understand the biology of these pathogens.  Although rickettsial pathogens have reduced genomes, the technical challenges of working with these organisms has resulted in relatively few genomes being available for organisms in the genus Anaplasma, with only two species, A. marginale and A. phagocytophilum, having more than a single strain that have been sequenced, while A. centrale, A. ovis and A. platys are represented by a single strain each.  Even for E. coli, approximately 35% of the genes lack a known function, and for these rickettsial organisms the percentage of the genome encoding genes of unknown function is a bit higher.  Ascribing function to previously uncharacterized genes is painstaking work; we have employed both comparative and functional genomic approaches in attempts to reveal the biology of these pathogens.  Comparative genomics analyses have provided some insight into mechanisms of persistence, have highlighted issues with species definition, and generated candidate lists of genes involved in tick transmission, however, many comparative analyses result in candidate gene lists, and without robust genetic systems in place we are unable to test these candidate genes for phenotype.  Anaplasma marginale has been transformed only twice, however a breakthrough transposon mutant library was recently developed for A. phagocytophilum which has provided information on essential genes and provides a tool for characterizing genes of interest.  Recent studies to elucidate the effectome – the set of proteins translocated by the type IV secretion system - of Anaplasma will be presented.

Hein Sprong Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, the Netherlands Dr. Hein Sprong obtained his PhD-degree in Medicine from the University of Amsterdam in 2001. He worked as a postdoc at the Max-Planck Institute of Molecular Cell Biology and Genetics in Dresden and became assistant professor at the Faculty of Chemistry of the Utrecht University. Since 2007, he works at the Dutch Centre for Infectious disease Control of the National Institute of Public Health and the Environment. Currently, he heads a multidisciplinary team of researchers that bridges the ecology and epidemiology of wildlife and vector-borne zoonoses. He has been involved the FP7 ANTIDotE project, which aimed to develop an anti-tick vaccine that protects against multiple tick-borne diseases. Since 2019, he is the consortium leader of VectorNet, a joint initiative of EFSA and ECDC, which supports all aspects of the European collection of data on vectors and their pathogens, related to both animal and human health. Ixodes ricinus-borne disease risk: disentangling tick and pathogen life cycles The density of questing Ixodes ricinus nymphs infected with tick-borne pathogens is one of the parameters that determines tick-borne disease risk. Vertebrate species contribute differently to the feeding and propagating ticks, and differ in pathogen competence: the ability to transmit a pathogen to ticks. Therefore, we investigated how wildlife communities contribute to tick-borne disease risk. The density of I. ricinus nymphs infected with Borrelia burgdorferi sensu lato, Neoehrlichia mikurensis and Anaplasma phagocytophilum among forest sites were correlated to the density of mammals and birds, determined by (camera) trapping and mathematical modelling. We found that the density of I. ricinus nymphs was positively associated with ungulates, and negatively associated with leporids and foxes. The density of nymphs infected with a pathogen increased with the density of competent hosts: rodents for B. afzelii and N. mikurensis, ungulates for A. phagocytophilum and birds for B. garinii and B. valaisiana. The density of nymphs infected with B. miyamotoi increased with the density of questing nymphs and with rodent density. Remarkably, increasing densities of rodents were associated with decreasing densities of nymphs infected with bird-associated Borrelia. An increasing diversity of the vertebrate community was not associated with decreasing densities of questing Ixodes ricinus nymphs. In a separate field study, rodent densities were manipulated in plots of 2500 m2 by (mock-)supplementing acorns or by rodent trapping during two years. The density of nymphs infected with pathogens were correlated with the (fluctuations in) rodent densities. Strong positive associations between rodent density and the density of nymphs infected with B. afzelii or N. mikurensis were found. Pathogens that predominantly rely on vertical transmission, for example Borrelia miyamotoi, only showed moderate associations between rodent density and the density of infected nymphs. Remarkably, the infection prevalence of nymphs infected with B. garinii, decreased with increasing rodent density, but the density of B. garinii-infected nymphs remained stable. Furthermore, temporal fluctuations in rodent densities did not result in detectable fluctuations in tick and pathogen densities. Our results draw attention to the importance of considering spatial and temporal scales as well as transmission modes of tick-borne pathogen in the generation of Ixodes ricinus-borne disease risk.

Ben Mans Agricultural Research Council - Onderstepoort Veterinary Research, South Africa Ben Mans has worked in the field of tick-host interaction for the last 26 years focusing on the evolution of blood-feeding behavior. His interests range from protein functional evolution, tick genomics, physiology, proteomics, transcriptomics, tick systematics and how these integrate to allow a reconstruction of the events that led to blood-feeding behavior in ticks. Other focus areas include diagnostics, epidemiology, genetic diversity and genomics of tick-borne parasites and development of anti-tick and parasite vaccines. He is a Principal Researcher at the Agricultural Research Council - Onderstepoort Veterinary Research (South Africa) in the Epidemiology, Parasites and Vectors division. Paradigms in tick evolution Ticks adapted to a blood-feeding lifestyle by evolving various mechanisms unique to tick biology. This includes mechanisms to detect the host, modulate the host immune and hemostatic systems, and process and digest the blood meal and eliminate excess water derived from the blood meal. Evolution of these mechanisms entailed novel structural and morphological innovations and/or exaptation of existing structures for blood feeding. This included genetic innovations that allowed evolution of new functions involved at the feeding interface. Not only did these innovations need to be efficient and specifically suited to its functional purpose to allow effective feeding, but had to evolve within existing biological frameworks that shaped and influenced the evolutionary trajectories followed by different tick lineages. The unique biology of different tick lineages may be explored and interpreted from this perspective to allow a synthesis of shared and novel characters that define ticks as monophyletic, obligate blood-feeding arachnids that nonetheless display remarkable lineage specific diversity. The reconstruction of ancestral characters enable contextualization of these paradigms, while technological advances illuminate the complexities involved in the mechanisms behind blood-feeding. For such reconstruction accurate systematic frameworks is essential that require the use of extensive systematic markers that may include mitochondrial genomic and nuclear phylogenomic approaches. A robust understanding of tick biology requires integration of knowledge from different disciplines that will allow definition and description of a fundamental and holistic model of tick evolution. Essential to this endeavor is the construction well annotated sequence databases and empirical confirmation of predicted functions encoded by proteins involved in tick-host interactions.

Jeremy Gray UCD School of Biology and Environmental Science, University College Dublin, Ireland Jeremy Gray obtained his PhD in Animal Parasitology from the University of London in 1972 and shortly afterwards took up a lecturing post in University College Dublin, remaining there to teach animal parasitology for more than 30 years, focusing initially on infections of farm animals, and latterly on zoonoses. His research on the tick Ixodes ricinus and the pathogens that it transmits (especially Babesia divergens and Borrelia burgdorferi) commenced soon after his arrival in Ireland. Related activities over the years included leadership of the EU programme on Lyme borreliosis, EUCALB, which eventually gave rise to ESGBOR, a study group of the European Society of Clinical Microbiology and Infectious Disease. He left the university in 2008, but as an Emeritus Professor has been able to maintain fruitful working relationships with colleagues at UCD and in many other parts of the world, greatly facilitated by his association since its inception with the journal Ticks and Tick-borne Diseases. Ixodes ricinus – a personal perspective Ixodes ricinus, the most abundant tick in northern and eastern Europe, has been the subject of scientific research for approximately 90 years, and more papers have been published on this tick species than on any other. This presentation will consider past, present and potential future studies. Early research, in the 1930s and 1940s, concerned the tick's role as a disease vector and parasite of farm animals in northern Britain, with attention subsequently shifting to the transmission of zoonotic tick-borne encephalitis in central and eastern Europe. Another surge of interest in I. ricinus resulted from its incrimination as a vector of Lyme borreliosis in the 1980s, and since then there has been a marked increase in studies on the detection of pathogens in questing stages, mainly driven by the advent of molecular methods. There are now many ongoing and developing studies on I. ricinus, but since it is impossible to pay appropriate attention here to every topic, three in particular will be briefly considered. The methods involved in the identification of vertebrate hosts by analysis of blood-meal remnants, a potentially a powerful tool for the study of tick-borne disease ecology, will be reviewed together with recent progress in its use in the field. Genetic variation between vector populations, particularly in relation to ecology and pathogen transmission, has received little attention so far, but there are now indications that important differences may occur between discrete populations of I. ricinus. The evidence will be reviewed and suggestions made for further research. Lastly, recent observations on the apparent effects of climate change on the distribution of I. ricinus will be described, evidence for effects on disease transmission examined and possible future scenarios discussed.

 

KEYNOTE SPEAKERS

 

Gad Baneth School of Veterinary Medicine, Hebrew University, Israel Dr. Baneth is a full professor of Veterinary Parasitology and Infectious Diseases at the Hebrew University of Jerusalem in Israel. Dr. Baneth graduated from the Hebrew University Koret School of Veterinary Medicine in Israel in 1990. He did a Small Animal internship and residency at the Hebrew University until 1994 followed by a fellowship in Internal Medicine and Infectious Diseases Research at the College of Veterinary Medicine, North Carolina State University during 1994 and 1995. He received a PhD in veterinary parasitology from the Hebrew University in 2000. Prof. Baneth served as the head of the Small Animal Internal Medicine Department at the Hebrew University Veterinary Teaching Hospital. He is a diplomate of the European College of Veterinary Clinical Pathology (ECVCP), an associate member of the European Veterinary Parasitology College (EVPC) and an editorial advisory board member for the Journal Veterinary Parasitology since 2006. He is the vice president of the LeishVet group for standardization of the diagnosis, treatment and prevention of canine leishmanioasis, a member of Board of Directors, Israel Society for Parasitology, Protozoology and Tropical Diseases, and a founding member of the Tropical Council for Companion Animal Parasites (TroCCAP). Dr. Baneth was the chairman of the World Small Animal Veterinary Association (WSAVA) Scientific Advisory Committee (SAC) during 2014-2015 and was an advisor to the European Food Safety Authority (EFSA) on leishmaniosis. Dr. Baneth heads a laboratory on infectious diseases. His research interests focus on the pathogenesis, diagnosis and treatment of veterinary and zoonotic vector-borne infectious diseases including leishmaniosis, relapsing fever borreliosis, canine ehrlichiosis, babesiosis, hepatozoonosis, trypanosomiasis and dirofilariasis.  Dr. Baneth is involved in the study of zoonotic and veterinary diseases in the Mediterranean Basin, Uzbekistan, Ethiopia, Southern Europe and South. He is the author of more than 270 scientific publications and book chapters. He is currently the director of the Koret School of Veterinary Medicine at the Hebrew University in Israel. Tick-borne relapsing fever caused by Borrelia persica, epidemiology, transmission pathways and animal reservoirs Relapsing fever is an acute infectious disease caused by spirochetes of the genus Borrelia in the family of Borreliaceae. The disease in humans is characterized by spirochetemia with episodes of fever, separated by afebrile intervals. Tick-borne relapsing fever caused by Borrelia  persica and transmitted by the tick Ornithodoros tholozani is common in Israel and other countries in the Near East extending from India and Central Asia to Egypt. Human infection is Israel is frequently associated with entrance to caves or ruins where the host tick is abundant. Borrelia persica has been found to cause infection and disease in domestic cats and dogs. We studied the life cycle and transmission of B. persica under natural conditions and in an experimental model using membrane feeding and maintaining the life cycle of the tick in all stages by artificial feeding. We also determined tick blood meal origins and detected B. persica infection in wildlife animals for the characterization of transovarial and transstadial transmission patters. The results of these studies indicated that B. persica is mainly transmitted transstadially while transovarial transmission is minimal. Borrelia persica infects a variety of wildlife mammals including wildlife canids such as golden jackals (Canis aureaus) and red foxes (Vulpes vulpes), rock hyraxes (Procavia capensis) and also rodents. Infection in O. tholozani ticks was significantly associated with the presence of blood meals in general and specifically with blood meals from golden jackals and red foxes. This strongly suggests that wildlife canids are natural reservoirs for B. persica infection and are potentially able to transfer infection between remote populations of O. tholozani ticks in remote caves and shady environments.

Ard Nijhof Institute for Parasitology and Tropical Veterinary Medicine, Freie Universitaet Berlin, Germany Ard Nijhof grew up in the Netherlands, where he qualified as a Doctor of Veterinary Medicine in 2004. From 2005 until 2010 he worked as a PhD student at the Utrecht Centre for Tick-borne Diseases (UCTD) from the Faculty of Veterinary Medicine, Utrecht University on a Wellcome Trust funded project entitled ‘Adapting recombinant anti-tick vaccines to livestock in Africa’. During his PhD he was a visiting researcher at the Department of Biochemistry from the University of Pretoria, South Africa. In 2011 he moved to Germany to work at the Institute for Parasitology and Tropical Veterinary Medicine of the Freie Universitaet Berlin (FUB) where he became a professor for veterinary arachno-entomology in 2019. He is currently heading a junior research group on tick-borne zoonoses at FUB which focuses on the development of novel tools for the genetic manipulation of ticks and the evaluation of artificial tick feeding methods for use in in vitro infection models. Since 2021, Ard Nijhof also is the Editor-in-Chief of the Ticks and Tick-borne Diseases journal. CRISPR-mediated genome editing in Rhipicephalus microplus ticks Recent years have seen an enormous increase in genomic data on ticks and tick-borne pathogens. Unravelling tick gene function may advance the development of novel control methods to improve human and animal health. Currently, gene silencing by RNA interference (RNAi) is the most widely used tool to examine tick gene function. Despite its many advantages, RNAi does have some limitations, as it is for instance not easily applicable all tick life stages, its knockdown effect is transient and complete gene silencing is rarely achieved. CRISPR-Cas9 based gene editing has the potential to overcome many of these disadvantages and has found wide use in other arthropod species such as mosquitoes. In this proof-of-principle study, we examined the possibility of inducing CRISPR-Cas9 based gene editing in Rhipicephalus microplus ticks by delivery of the CRISPR/Cas9 ribonucleoprotein complex (RNP), consisting of the Cas9 protein and single guide RNA (sgRNA), by injection in engorged females followed by electroporation. The distalless (dll) gene was selected as a target, as previous studies in other arthropods showed that it is essential for limb development. Successful CRISPR-Cas9 based alteration of the dll gene is expected to create frameshift mutations causing aberrant limb development. Transovarial RNAi studies in R. microplus as well as Ixodes ricinus ticks confirmed that dll gene silencing during embryogenesis resulted in aberrant larvae with missing or malformed legs. Five different sgRNAs targeting the first exon of the dll gene from R. microplus were designed and their cutting activity was confirmed in in vitro cleavage assays. Combinations of the Cas9 protein with single sgRNAs or sgRNA mixtures in different mole ratios were injected in groups of engorged R. microplus females. These groups were exposed to different electroporation conditions and subsequently allowed to oviposit. Larvae that hatched were screened phenotypically under a stereomicroscope. DNA was extracted from aberrant larvae and subjected to PCR for dll sequence analysis. A proportion of the larvae that hatched from females injected with Cas9 and dll sgRNAs showed aberrant phenotypes such as missing or malformed legs that were not found in the control groups. DNA sequencing confirmed mosaic mutations including insertions and deletions at the expected cutting sites. These results demonstrated that CRISPR-mediated genome editing can be performed by the injection of Cas9 protein with sgRNAs in engorged female ticks followed by electroporation. Further studies are required in order to optimize this method and to determine its suitability for knock-in editing in ticks.

Olivier Duron French National Centre for Scientific Research (CNRS), Montpellier, France Olivier Duron is an evolutionary ecologist interested in the diversity of interactions between microbes and hosts. After a PhD in parasitology at the University of Montpellier (France) in 2005, Olivier Duron obtained a Marie Curie postdoctoral fellowship and joined the University College London (UK). He then held a second postdoctoral position at the University of Liverpool (UK) and he shortly afterwards took up a research position at the Centre national de la recherche scientifique (CNRS) in Montpellier. Since 2020, he has been a senior researcher at CNRS in the MIVEGEC laboratory (France). His current projects focus on how maternally inherited symbionts influence diversity, ecology, vector competence and reproduction of ticks. Other research interests include the study of novel tick-borne disease agents in South American rainforests. Nutritional endosymbiosis in ticks Ticks rely exclusively on vertebrate blood at all stages in their development. They are consistently exposed to nutritional deficiencies: Blood is rich in some nutrients but relatively poor in others, like B vitamins. Almost all tick species examined harbour a nutritive obligate endosymbiont, Coxiella-like endosymbionts (CLE) or Francisella-LE (FLE) in most cases, or Rickettsiales endosymbionts in few cases like in the Ixodes genus. No other bacterium is so uniformly present in ticks. Each of these bacterial endosymbionts is able to synthesize at least two (for Rickettsiales) or three (for CLE and FLE) B vitamin types and to further provision their tick hosts. Elimination of these nutritive endosymbionts negatively impacted tick life history traits and prevented the development of viable adult females. An oral supplement of B vitamins restored these deficiencies showing the central role of these vitamins for the tick life cycle. However, despite the co-evolved and obligate nature of these mutualistic interactions, the structure of tick’s microbiomes does not mirror the tick phylogeny with a clear exclusion pattern between CLE and FLE across tick species. CLE, but not FLE, commonly form evolutionarily stable associations with ticks commonly leading to co-cladogenesis as observed in the Rhipicephalus and Amblyomma genera. Symbiont replacements is yet obvious during radiation of Amblyomma, with recent, and likely ongoing, invasions by FLE and subsequent replacements of ancestral CLE through transient co-infections. Nutritional endosymbiosis in ticks is thus not a stable evolutionary state, but instead arises from conflicting origins between unrelated but competing bacterial endosymbionts with similar metabolic capabilities. This conflicting processes underscores the important contribution of nutritional endosymbiosis to the first appearance of ticks and their later diversification to current species.

Gerhard Dobler Bundeswehr Institute of Microbiology, Germany Gerhard Dobler is a physician. After study of human medicine he specialized in medical microbiology and epidemiology of infectious diseases. After spending a year at the Institute of Tropical Medicine in Munich his interest arouse for tropical viruses and bacteria transmitted by arthropods. In 2004 he was appointed head of the Department of Virology and Rickettsiology at the Bundeswehr Institute of Microbiology in Munich. Since then he is doing research on tick-borne and mosquito-borne viruses and rickettsiae. His special interest is on tick-borne encephalitis and in 2016 he was appointed head oft he German national reference laboratory for tick-borne encephalitis. Since 20219 he holds a honorary professorship for virology at the Department of Parasitology in the Institute of Zoology of the University of Hohenheim, Germany.  His interests are ranging from diagnostics of TBE and mechanisms on vaccine failures to epidemiology of emerging TBE in Europe and especially understanding of the transmission of TBE natural foci. The phylo-epidemiology of TBE virus in Central Europe Tick-borne encephalitis (TBE) is the most important tick-borne viral infection in Europe and Asia. It is caused by TBE virus, a member of the genus Flavivirus in the family Flaviviridae. So far, at least five different subtypes of TBE virus can be distinguished using molecular genetic analysis. In Central Europe, so far only the European subtype has been detected. During the last years, more than 200 TBE virus strains from > 50 different TBE virus natural foci have been isolated and genetically characterized. These data show that many different strains circulate in Germany and countries of Central Europe. So far, at least nine different genetic clades within the European subtype of TBE virus have be detected. Further analyses show that the virus is genetically stable. Comparative studies of TBE virus strains from the same natural focus over a period of 40 years show the genetic identity of TBE virus in this time frame. Even in long established natural foci, which are located close to each other, the TBE virus strains may be genetically different. This implies that each of these foci was established by a separate introduction of a different TBE virus strain or evolved into a distinct TBE virus genotype over time. However, meanwhile also a continuous spread of virus over larger distances could be documented. Comparing the TBE virus strains on a local and regional level, the data show that TBE viruses in Germany are imported in Southern Germany mainly from the South-eastern part of Europe (Austria, Czech Republic, Slovak Republic). Recent isolates in Northern Germany show a close genetic relationship to TBE virus strains from Finland and from Poland. The data imply that there is a continuous influx of TBE virus into Germany from different directions. As a long-distance way of spread bird migration is implicated. In some instances, a continuous spread from one location to a neighbouring place was demonstrated implying migration of terrestrial wild animals or transport of domestic animals as ways of spread.

Stephen Barker University of Queensland, Australia Stephen Barker is a Professor of Parasitology. Barker has been studying ticks and other ectoparasites at the University of Queensland in Brisbane, Australia, for over 25 years. Recent activities include: (i) a monograph, with Dr Alan Walker (University of Edinburgh), on the “Ticks of Australia: the species that infest domestic animals and humans”; (ii) resolution of some old chestnuts in the systematics of the ticks (from entire mitochondrial genome sequences) which led to the description of two new genera of ticks, Robertsicus and Archaeocroton, and a proposal of another new genus; and (iii) development of the Tick Mitochondrial Genome Network. What have we learned from the first 600 mitochondrial genomes of ticks and other Acari? Mitochondrial genomes have been remarkably instructive about the evolutionary-history (phylogeny), population-genetics and phylogeography of Acari, particularly the ticks. At present we have entire mt genomes for 125 of the 896+ species of ticks (316 mt genomes in total), and for 146 of the thousands of other species of Acari (296 mt genomes in total). Total number of mt genomes available for the Acari is 612 [we aim to have mt genomes for 300+ species of ticks and other Acari by 2025 in time for the 11th International Congress of Ticks & Tick-borne Disease]. It has never been easier to sequence entire mt genomes. Any lab with basic wet lab capability can do this by using commercial sequencing companies. In 2021, Barker & Kelava precipitated the Tick Mitochondrial Genome Network with a YouTube Channel of the monthly meetings: link below. Selected insights and outcomes will be discussed in our talk, including: (i) Phylogenetic trees that led Ben Mans and us to propose that the genus Carios s.l. be dissolved and the subgenera Alectorobius, Antricola, Nothoaspis, Reticulinasus and Subparamatus be raised to genus level. (ii) An extraordinarily re-arranged mt genome arrangement in Amblyomma (Africaniella) transversale that prompted us and others to re-elevate the subgenus Africaniella to a genus. (iii) Recent insights into the phylogeny of the genera Robertsicus, Archaeocroton, Nuttalliella, Amblyomma and Haemaphysalis.(iv) The tick-box motif may be involved in the insertions of 132 to 312-bp in two Haemaphysalis species (H. (Al.) inermis and H. (Al.) kitaokai) and R. (B.) geigyi. (v) Assignment of several ticks to subgenera including: Ixodes woylie andI. barkeri to Endopalpiger. (vi) Realization that Ixodes anatis, the kiwi tick, may be closely related to the ticks of marsupials of Australia and Papua New Guinea.

Jose De la Fuente Instituto de Investigación en Recursos Cinegéticos, IREC, Ciudad Real, Spain Graduated in Physics at Moscow State University and University of Havana. Ph.D. in Biology at University of Havana. Research career: Switzerland (Institute for Molecular Biology I, ETH, University of Zurich), Cuba (Center for Genetic Engineering and Biotechnology, Havana), United States (Oklahoma State University, Stillwater) and Spain (Instituto de Investigación en Recursos Cinegéticos, Ciudad Real). Current position: Professor, SaBio, IREC (CSIC-UCLM), Spain, and Adjunct Professor, Department of Veterinary Pathobiology, CVHS, OSU, U.S.A. Thirty-five years experience in research, education and as Principal Investigator in research projects. Over 600 published papers and 5 books edited. Patents: 31. PhD thesis supervised: 32. Current Research Interests: host-vector-pathogen molecular interactions, and translation of this basic information into development of effective vaccines and other interventions for the control of infectious diseases affecting human and animal health worldwide. Tick-host-pathogen interactions: a vaccinomics approach to control tick-borne diseases 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. However, major challenges such as host immunity, pathogen and environmental factors and vaccine efficacy and safety need to be addressed. Vaccinomics provides a platform to address these challenges and improve vaccine efficacy and safety. The immune system contains random processes such as immunoglobulin recombination events and the direct correlation between atomic coordination and peptide immunogenicity that support quantum immunology. In similarity with Albert Einstein’s definition of the photon as a quantum of light, the immune protective epitopes were proposed as the immunological quantum. Quantum vaccinomics is the platform proposed for the identification and combination of antigen protective epitopes, the immunological quantum, for vaccine development. Quantum vaccinomics will contribute to vaccine development, efficacy and safety by facilitating antigen combinations to target pathogen infection and transmission in emerging infectious diseases.

Janet Foley UC Davis School of Veterinary Medicine, USA Janet Foley is a veterinarian and disease ecologist in the School of Veterinary Medicine at the University of California, Davis. Growing up in New England, early influences included her father who was an avid outdoorsman and hunter. After living briefly in northern Germany, she obtained her BA in religion and BS in evolution before settling in Davis, California to study for the DVM and a PhD in ecology. She is now a professor in vector-borne disease epidemiology and director of the Masters in Preventive Veterinary Medicine program. Her research expertise is in disease in populations, wildlife-human interactions, disease persistence theory, and tick-transmitted disease. She is the PI for the tick research focus in the PacVec CDC-funded Center of Excellence for Vector-Borne Disease. When do ticks invade? Invasive tick species and the pathogens they vector pose increasing threats to human and animal health around the world. Invasion may be expansile, increasing the contiguous range of a tick, or occur due to long distance transport and introduction to a new region. Techniques like niche or movement models highlight locations at risk of novel tick establishment, but less attention has been paid to particular characteristics, and species that have these characteristics, and are thus most likely to invade. Here we briefly overview invasion biology, which is the study of how organisms come to be introduced into a new area and establish themselves with some probability of local persistence. We analyze examples of tick invasion events in North America in order to identify those characteristics of the invasive tick species that facilitated the invasion. Our case studies include brown dog ticks, American dog ticks, Asian longhorned ticks, Amblyomma species and others. Ticks with the identified common characteristics are likely to be ones that will invade in the future. Commonalities among invasive ticks are that they thrive in anthropogenically modified habitats, feed on either domestic animals or wildlife that occur in high density, and can survive across a broad range of climatic conditions. Our invasion examples varied widely in life history and reproductive characteristics. We also assess environmental factors that underlie invasion such as climate, habitat, and societal changes. Identifying patterns and key components of the process may help guide surveillance and inform prevention and intervention programs to lessen the consequences associated with invasive tick-borne disease.

Olaf Kahl Tick-Radar GmbH, Berlin, Germany Olaf Kahl began working on ticks in 1978. His main interest has been the ecology and the ecophysiology (life cycle, diapause, water balance) of Central European ticks. Moreover, he has been working on the vector role of ticks for Borrelia burgdorferi sensu lato. He received his doctoral degree and his habitation at the Free University of Berlin (Germany) in 1989 and 1998, respectively. He has been a regular co-organiser of a tick conference now called International Symposium on Ticks and Tick-borne Diseases since 1995. After working at the former Publishing House Blackwell from 1999 to 2003, he became a freelancer. He has been a CEO of the small company tick-radar GmbH since 2009 with research focus on the field ecology of Central European ticks. In the same year, he became the Managing Editor of the newly launched journal Ticks and Tick-borne Diseases (Elsevier). Vector competence of ticks for zoonotic agents: The basics and where are we now? Ticks take up various microbial agents during their large blood meals on vertebrate hosts. Some species are capable of maintaining their infection and transmitting certain agent(s) to another host when feeding again in a later life stage. They act as vectors. Tick-borne pathogens circulate between vector tick species and (vertebrate) reservoir hosts in so-called natural foci, an eminent concept developed by E. Pavlovsky in the late 1930s. They are usually harmless for wild and adapted animals, but they can be pathogenic to humans and/or domestic animals and may cause more or less serious disease in them. It is therefore important to know which tick species are involved in such natural foci. This knowledge opens up the possibility to investigate the specific tick-pathogen relationships and to learn about the ecological conditions under which a given tick-borne pathogen can perpetuate, a prerequisite to initiate effective control measures. What seems rather simple at first glance − but usually is not − is to check the possible vector competence of a given tick species for a certain pathogen. This makes it necessary, as a rule, to carry out transmission experiments, which can be difficult and costly to perform, especially if the pathogen is dangerous and protected vertebrate species are involved in its circulation. Thus far the theory, simple and clear. Due to the increasing availability of modern, very powerful detection techniques, however, a multitude of microbial agents and parasites (new species or new genotypes) have been described, often only by identification of relatively small parts of their DNA/RNA in questing or feeding ticks in recent years. On this vague basis authors often erroneously call these ticks vectors and not carriers, which would be the correct term. As a result, it is extremely difficult to maintain a clear overview of proved vector tick species on the one hand versus only incriminated vector tick species on the other hand, a highly unsatisfying situation. This introductory contribution shall set the scene in the symposium on vector competence and the following discussion.

Alina Rodríguez-Mallon Center for Genetic Engineering and Biotechnology, Habana, Cuba Dr. Alina Rodríguez Mallon has a Bachelor in Biochemistry and a PhD in Molecular Biology at the Havana University in Cuba. She received post-doctoral training with an ICEGB fellowship at the Prof. Di Lauro’s laboratory in Naples, Italy and in the laboratory of Prof. Hans Shöeler at the European Molecular Biology Laboratories in Heilderberg, Germany on stem cell culture and knock out mice technology. Since her bachelor graduation in 1990, she has been a researcher in the Center for Genetic Engineering and Biotechnology in Havana, Cuba, working on molecular biology and genetic engineering. She is presently the head of the Animal Biotechnology Department at CIGB and the Principal Researcher in the “Antigens against ticks” Research Project. She is also Associate Professor in the Biology Faculty at the Havana University. She is a member of the CIGB and BioCubaFarma Scientific Councils and also a member of the World Society of Tropical Veterinary Medicine. Alina and her group have been recognized on several occasions with Annual Awards from the Cuban Academy of Sciences for their contributions to Biotechnology in Cuba. She holds the Carlos J. Finlay order, which is the highest distinction awarded by the Cuban government to nationals and foreigners for their contributions to the development of science. She is interested in the study of ticks and tick-borne diseases, as well as the tool development for their control. She is also interested in the development of vaccines and diagnostic means for veterinary use in general. Anti-tick vaccines as a practicable alternative to control ticks There are increasingly frequent reports of multi resistant tick strains to chemical acaricides. In this current situation, vaccination becomes in a very attractive alternative to control these ectoparasites. However, the challenge of research community working on anti - tick vaccines is to get effective antigens with a broad action spectrum in spite of the biochemical complexity of this multicellular parasites and their contact with the host immune system only during feeding. Bm86 vaccination against Rhipicephalus microplus has demonstrated the feasibility of the tick immunological control under field conditions when used as part of an integrated management strategy. The universal character of this program is given by the wide possibilities for full adaptation of autochthonous practices in different regions to the main vaccine backbone. The most important impacts of these Programs applied in Cuba and other countries have been the tick infestation reduction after two or three generations feed on vaccinated animals, diminution in the incidence of hemoparasitic diseases and a dramatic reduction in the use of chemicals. However, obtaining new effective antigens against other tick species becomes of great relevance in order to improve the practical application of these vaccines. Although a successful proof of concept in laboratory conditions against different tick species has been obtained by host vaccination with an antigen based on a peptide from the tick P0 ribosomal protein, to get an anti-tick vaccine, a development pathway is necessary to be performed in which effective formulations for different host species and their scale up production processes will be set up. In this development process, the establishment of a validated and robust analytic system to guarantee the vaccine consistence and quality is also addressed before assuming clinical trials for the sanitary register.

Richard Wall University of Bristol, UK Richard Wall is professor of Zoology at the University of Bristol.  He has over 30 years of research experience in studies of the ecology, behaviour and epidemiology of parasitic arthropods and arthropod-mediated disease in animals.  Recent workhas included large-scale surveillance programmes for assessing tick and flea prevalence on companion animals and livestock and the development of novel biological tools for louse, mite and tick control.  Professor Wall has written or co-authored over 200 research publications plus three textbooks.  He was veterinary editor of the journal “Medical & Veterinary Entomology” for eight years and in 2013 he was awarded the WAAVP/Bayer Prize for research excellence in veterinary parasitology.  Professor Wall has been involved in numerous international collaborative projects in Africa, India and South east Asia. Essential oils for the prevention of tick attachment to humans and companion animals Plant essential oils show promise as natural alternatives to synthetic tick repellents and could make a valuable contribution to integrated tick management programmes for both humans and their companion animals. However, while many studies report their efficacy in the laboratory, few extend these investigations to in vivo or field trials. Here we present the results of studies which examined the use of essential oils to prevent tick bites on both humans and dogs. First, for humans, simultaneous blanket-drags and standardised walks were employed to evaluate the acquisition of Ixodes ricinus by 1m2 cotton blankets or cotton trousers, in woodland edge habitats of known high tick abundance. Blankets and trousers had been treated with one of 5% oregano, rosemary, spearmint or thyme oils, 20% DEET (N,N-Diethyl-3-methylbenzamide) (positive control) or ethanol excipient-only (negative control). The number of ticks present on the blankets or trousers differed significantly between treatments: spearmint oil treatments resulted in significantly fewer ticks than the negative controls for both blankets and trousers and significantly fewer ticks were present on the oregano oil treated blankets. No reduction in repellence was detected over a 24 h period between treatment and testing. For dogs, spearmint, turmeric, thyme, ginger and geranium were able to abolish the orientation and taxis of Ixodes ricinus towards sebum extracted from dog hair in initial laboratory assays. Subsequently blanket-drag field assays were used to show that tick acquisition rates were as low on blankets impregnated with turmeric oil as with 20% DEET. Finally, in a participatory in vivo trial, tick acquisition by untreated control dogs was compared with dogs sprayed with turmeric oil and 16 dogs sprayed with orange oil (both 2.5 % v/v diluted in water with a 1% coco glucoside excipient) before each walk, in known tick infested areas. The percentage of dogs with ticks attached to the legs or belly when sprayed with turmeric oil suspension was significantly lower than that of ticks attached to the same areas of dogs sprayed with a positive control or untreated dogs. The results suggest that some essential oils, particularly thyme and spearmint, exhibit considerable potential as effective natural tick repellents for application to clothing or animals, with effective equivalence to 20% DEET.

Monica Florin-Christensen Institute of Veterinary Pathobiology, Buenos Aires, Argentina Monica Florin-Christensen has worked in scientific research for over 35 years, mostly in physiological and molecular biological aspects of several lower eukaryotes, including the free-living ciliate Tetrahymena thermophila and the parasites Babesia bovis, Trypanosoma cruzi and Pneumocystis carinii, among others. She got her Ph.D. in Biological Sciences at the University of Buenos Aires, Argentina, and has worked in different laboratories in her home country as well as in USA, Denmark and Germany. For the last 18 years, she has been a Senior Researcher of the National Research Council of Argentina (CONICET) at the Institute of Veterinary Pathobiology, Institute of Agricultural Technology (INTA), Argentina. Her main current focus is the identification and characterization of molecules of parasitic protozoans that act at the host-pathogen interplay and that can be targets for the development of therapeutic interventions. She also teaches undergraduate and graduate university courses on molecular genetics and microbiology. Degrade to survive: the intricate world of piroplasmid peptidases Piroplasmids belonging to the Babesia and Theileria genera are tick-transmitted parasites with high impact on men and animals. These parasites possess sexual and asexual phases occurring in the definitive arthropod and vertebrate hosts, respectively. Fulfilling their complex life cycles requires the coordinated execution of numerous metabolic pathways of degradation and synthesis. As well as other parasitic protozoa, piroplasmids are equipped with different types of peptidases to fulfill many of such essential processes. Despite their perceived importance, the functional significance of these peptidases remains poorly characterized. Typically, piroplasmids contain around 60 putatively active serine, metallo, cysteine, aspartic and threonine proteases, which are present soluble in the cytosol, inside organelles, bound to the membrane or secreted to the extracellular medium, and are well conserved among species. These parasites also express a similar amount of non-functional protease homologues, with as yet unknown roles. In the vertebrate host, piroplasmid functional peptidases intervene in entry and exit to and from host cells, hemoglobin degradation, and intracellular protein degradation in the proteasome, while other possible functions include immune modulation, organelle maturation, apoptosis and virulence. Additionally, some proteases appear to be highly relevant for the development of parasite stages in the tick vectors. Consistent with their essential roles, blockade of some key proteases using inhibitors or antibodies hampers parasite growth, highlighting their potential usefulness in drug therapies and vaccine development against piroplasmid infections of domestic animals and men. It can be concluded that a better understanding of the functional significance of piroplasmid peptidases will certainly contribute to the improved control of many devastating human and animal diseases (Supported by INTA projects I102 and I105).

Alejandro Cabezas Cruz UMR BIPAR (INRA, Anses, EnvA), Maisons-Alfort, France After graduation as Doctor in Veterinary Medicine in 2006, Alejandro joined the Center of Genetic Engineering and Biotechnology (CIGB), in Havana, where he was involved in the study of molecular biology, genetic engineering and biotechnology applied to tick control. In 2012, he obtained a Marie Curie scholarship and joined the EU-funded project POSTICK at the Institute of Parasitology in the Czech Republic and completed his Master in Parasitology. Then, in 2013 Alejandro enrolled in two PhD programs simultaneously and completed them in 2014 (Spain) and 2016 (France). After a brief post-doc, in 2017 he joined INRAE as a Principal Investigator at the UMR-BIPAR, France. Since 2012, Alejandro has published 160 manuscripts on different aspects of tick research. Recently, with his group, he introduced the concept of anti-microbiota vaccines, as an innovative approach for tick control and to develop transmission-blocking vaccines. His scientific results have been recognized by the scientific community and in 2017 he was awarded the 'Odile Bain Memorial Prize' for his outstanding contribution to Parasitology. Anti-microbiota vaccines, concepts and applications for Lyme and malaria control Ticks harbor microbial communities including pathogenic and non-pathogenic microbes. The relation between pathogens and the microbiome is bidirectional. Empirical evidence shows that pathogen acquisition modulates the tick gut microbiome, while at the same time the tick microbiome is a gatekeeper for pathogen colonization of tick tissues. Increased knowledge of microbial ecology and vector-host interactions is driving the emergence of new concepts and tools for vector and pathogen control. In 2020, the concept of anti-microbiota vaccines was presented to the community. Anti-microbiota vaccines modulate the taxonomic and functional profiles of the tick microbiome, as host antibodies taken in the blood meal target microbiota bacteria within hematophagous arthropods. Our initial studies show that host antibodies against a single bacterial species trigger cascading ecological effects on the whole microbiome with consequences for vector physiology and vector-pathogen interactions. In this keynote, we’ll present current knowledge and paradigms in tick microbiota research. We’ll also present our results on the use of anti-microbiota vaccines to block Borrelia and Plasmodium colonization in Ixodes ticks and Culex mosquitoes, respectively. Vector microbiota manipulation by host antibodies offers an alternative to develop effective transmission-blocking vaccines.

Laurence Vial Centre of International Cooperation in Agriculture Research for Development (CIRAD), Montpellier, France Laurence Vial is Doctor in Veterinary Medicine specialized in tick taxonomy, biology and vector competence. After a PhD in ecology and evolution at the University of Montpellier (France) in 2005, Laurence Vial was recruited in CIRAD to work on Ornithodoros soft ticks and their ability to maintain and transmit the African Swine Fever Virus in African countries but also in Europe. A few years ago, she also focused her attention in a new invasive hard tick establishing in south of France, Hyalomma marginatum, and the risk of local emergence of Crimean-Congo Haemorrhagic Fever. Her main interest is to understand how the whole socio-ecosystem in which ticks, vertebrate hosts and pathogens interact may affect the tick distribution, the dynamics of pathogen transmission and the emergence of diseases. Crimean-Congo Hemorrhagic Fever enzootic cycle and factors favouring virus transmission: special focus on France, an apparently free-disease area Crimean-Congo Hemorrhagic Fever (CCHF) is a viral zoonotic disease resulting in hemorrhagic syndrome in humans. Its causative agent is naturally transmitted by ticks to non-human vertebrate hosts within an enzootic sylvatic cycle. Ticks are considered as biological vectors but also reservoirs for CCHF virus (CCHFv), as they are able to maintain the virus for several months or years and to transmit CCHFv from ticks to ticks. Although animals are not symptomatic, some of them can sufficiently replicate the virus to become a source of infection for both ticks, as well as humans through contact with contaminated body fluids. The recent emergence of CCHF in Spain indicates that the geographic range of the virus is expanding. In other European countries like France, the presence of its main tick vector and the detection of CCHFv antibodies in animals, without necessarily human cases, suggest that CCHFv has been continuing to spread silently. Based on a systematic review of the literature, we investigated the different CCHF epidemiological cycles already known in endemic countries and determined the one as hypothesized in the French local context. This work made it possible to point out tick species that seem to be the best candidate vectors of CCHFv in France, but also to highlight the importance of the abundance and composition of local host communities on the infection prevalence of vectors. We also identified parameters that may influence the virus transmission among tick vectors and non-human vertebrate hosts. Considering all these components, we understand why tick vectors may remain weakly infected in France and predict a low probability of disease emergence in humans in the current situation. The likelihood of factors that can modify this equilibrium is discussed.

Attila D. Sándor University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Romania Dr. Attila D. Sándor has a PhD-degree in Zoology, obtained at Babes-Bolyai University, Cluj in 2012. He worked as conservation biologist, than started to work at the Parasitology Department of the Faculty of Veterinary Medicine of the University of Agricultural Sciences and Veterinary Medicine, Cluj in 2010. Since 2019, he also works at the Parasitology Department of the University of Veterinary Medicine, Budapest. He is primarily studying the ecology of host-vector-pathogen cycles of terrestrial vertebrates. His interests range from biogeography and distributions to vector competence, co-evolution and host-parasite adaptations in several study systems, with a special emphasis on bats and their ectoparasites. Geographical distribution, host selection and seasonality of occurrence in bat-specialist ticks of Europe To exploit most effectively their host resources, parasites are in constant race to counterbalance and overcome their host’s defense mechanisms. They not just actively seek for hosts but they use a number of adaptive strategies to increase their reproductive success and transmission (colonization of new hosts), like host specificity and seasonality in occurrences (synchronizing their reproduction to the hosts’ life cycle, etc.). Ticks are important parasites of vertebrates, which may show high prevalence and intensity and not only deprive their hosts from energy but they may vector a number of pathogens. European bat species are host for three specialist hard tick species (Ixodidae: Ixodes ariadnae, I. simplex and I. vespertilionis). Based on a review of published European hard tick records, here we report details on geographical distribution, host range and seasonality of infestation of these ticks on wild caught bats in Europe. Using georeferenced tick-host relationships we tested several hypotheses on host-parasite evolutionary adaptations regulating host-specificity, seasonality and sympatric speciation. While all three bat-specialists show sympatry in distribution, we observed significant differences between host specificity and the seasonality of abundance between the morphologically different bat specialist ticks (I. simplex vs. I. vespertilionis) likely caused by their host specificity and their respective host seeking behavior. The two highly generalist, but morphologically similar tick species (I. ariadnae and I. vespertilionis) showed temporal differences in occurrence and activity, thus exploiting significantly different host communities while occurring in local sympatry. Bat-specialist ticks show a wide range of adaptations to their hosts, with differences in specificity, seasonality of occurrence, the prevalence and intensity of infestation and all these contribute to a successful division of temporal niches of ticks sharing morphologically similar hosts occurring in geographic sympatry.