Martina Ličková , Bronislava Víchová , Markéta Derdáková , Monika Sláviková , Sabína Fumačová Havlíková , Dana Zubriková , Diana Selyemová , Michal Chvostáč , Lucia Blaňarová , Viktória Čabanová , Veronika Vaňová , Lucia Šulejová , Jana Kerlik , Tomáš Szemes , Katarína Šoltys , Boris Klempa
{"title":"Surveillance of tick-borne encephalitis virus foci in Slovakia: A seroprevalence study in ruminants combined with virus detection in ticks","authors":"Martina Ličková , Bronislava Víchová , Markéta Derdáková , Monika Sláviková , Sabína Fumačová Havlíková , Dana Zubriková , Diana Selyemová , Michal Chvostáč , Lucia Blaňarová , Viktória Čabanová , Veronika Vaňová , Lucia Šulejová , Jana Kerlik , Tomáš Szemes , Katarína Šoltys , Boris Klempa","doi":"10.1016/j.ttbdis.2025.102444","DOIUrl":"10.1016/j.ttbdis.2025.102444","url":null,"abstract":"<div><div>The tick-borne encephalitis virus (TBEV) is an important human pathogen that causes tick-borne encephalitis, a potentially fatal neurological disease. Human infections occur through tick bites or after the consumption of raw milk products from infected animals, causing alimentary outbreaks representing a significant public health problem in Slovakia. In the present study, a total of 1029 ruminant sera (from 672 sheep and 357 goats) from 18 localities, collected in Slovakia during 2017–2019 were initially screened for TBEV-specific antibodies by ELISA, and 98 (9.5 %) of them were confirmed as positive by the plaque reduction neutralization test or immunofluorescence assay. The differences in observed seroprevalence of 11.9 % (80/672) among sheep and of 5.0 % (18/357) among goats were significant. Tick screening was subsequently conducted near the surveyed farms where seropositive animals were identified. Overall, 2,534 ticks (2,528 <em>Ixodes ricinus,</em> 3 <em>Dermacentor reticulatus,</em> 2 <em>Dermacentor marginatus,</em> 1 <em>Haemaphysalis concinna</em>) from 7 collection sites were pooled and analysed by RT-qPCR, resulting in estimated prevalence of 2.86 % (ranging from 0.31 to 8.72 % at different sites). The estimated prevalence in adults was lower (2.15 %) than in nymphs (2.9 %). Positive ticks (all <em>I. ricinus</em>) and milk samples were then used for virus isolation. Three new cell culture isolates were prepared and sequenced. Obtained full-length genome sequences revealed high genetic diversity and phylogenetic clustering with virus strains found across Europe. The seroprevalence of TBEV in farm animals is an effective tool for identifying areas of virus circulation and guiding more in-depth field investigations of local tick populations. This combined approach of serological and virological surveillance provides valuable data for assessing the risk of alimentary TBEV infections and characterizing local TBEV strains.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 1","pages":"Article 102444"},"PeriodicalIF":3.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143168534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Seasonal activity patterns of Ixodes scapularis and Ixodes pacificus in the United States","authors":"Lars Eisen","doi":"10.1016/j.ttbdis.2024.102433","DOIUrl":"10.1016/j.ttbdis.2024.102433","url":null,"abstract":"<div><div>Knowledge of seasonal activity patterns of human-biting life stages of tick species serving as vectors of human disease agents provides basic information on when during the year humans are most at risk for tick bites and tick-borne diseases. Although there is a wealth of published information on seasonal activity patterns of <em>Ixodes scapularis</em> and <em>Ixodes pacificus</em> in the United States, a critical review of the literature for these important tick vectors is lacking. The aims of this paper were to: (i) review what is known about the seasonal activity patterns of <em>I. scapularis</em> and <em>I. pacificus</em> in different parts of their geographic ranges in the US, (ii) provide a synthesis of the main findings, and (iii) outline key knowledge gaps and methodological pitfalls that limit our understanding of variability in seasonal activity patterns. Based on ticks collected while questing or from wild animals, the seasonal activity patterns were found to be similar for <em>I. pacificus</em> in the Far West and <em>I. scapularis</em> in the Southeast, with synchronous activity of larvae and nymphs, peaking in spring (April to June) in the Far West and from spring to early summer (April to July) in the Southeast, and continuous activity of adults from fall through winter and spring with peak activity from fall through winter (November/December to March). In the colder climates of the Upper Midwest and Northeast, <em>I. scapularis</em> adults have a bimodal seasonal pattern, with activity peaks in fall (October to November) and spring (April to May). The seasonal activity patterns for immatures differ between the Upper Midwest, synchronous for larvae and nymphs with peak activity in spring and summer (May to August), and the Northeast, where the peak activity of nymphs in spring and early summer (May to July) precedes that of larvae in summer (July to September). Seasonality of human tick encounters also is influenced by changes over the year in the level of outdoor activities in tick habitat. Studies on the seasonality of ticks infesting humans have primarily focused on the coastal Northeast and the Pacific Coast states, with fewer studies in the Southeast, inland parts of the Northeast, and the Upper Midwest. Discrepancies between seasonal patterns for peak tick questing activity and peak human infestation appear to occur primarily for the adult stages of <em>I. scapularis</em> and <em>I. pacificus</em>. Study design and data presentation limitations of the published literature are discussed. Scarcity of data for seasonal activity patterns of <em>I. pacificus</em> outside of California and for <em>I. scapularis</em> from parts of the Southeast, Northeast, and Upper Midwest is a key knowledge gap. In addition to informing the public of when during the year the risk for tick bites is greatest, high-quality studies describing current seasonal activity patterns also will generate the data needed for robust model-based projecti","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 1","pages":"Article 102433"},"PeriodicalIF":3.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143170013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Carlo Croci , Luca Erriquez , Beatrice Bisaglia , Greta Bellinzona , Emanuela Olivieri , Davide Sassera , Michele Castelli
{"title":"Genome sequence of Ehrlichia muris from Ixodes ricinus collected in Italy on a migratory bird provides epidemiological and evolutionary insights","authors":"Carlo Croci , Luca Erriquez , Beatrice Bisaglia , Greta Bellinzona , Emanuela Olivieri , Davide Sassera , Michele Castelli","doi":"10.1016/j.ttbdis.2024.102409","DOIUrl":"10.1016/j.ttbdis.2024.102409","url":null,"abstract":"<div><div>Ticks are prominent vectors of several zoonotic diseases. Tick-borne pathogens include the members of the genus <em>Ehrlichia</em>, which are obligate intracellular bacteria infecting immune and hematopoietic cells. <em>Ehrlichia muris</em> predominantly affects rodents, but was also reported to be a human pathogen. The known geographical distribution of this bacterium ranges from Asia, to the USA and eastern Europe. In the present work, we report the finding of <em>E. muris</em> in an <em>Ixodes ricinus</em> tick collected from a migratory bird (<em>Turdus iliacus</em>) in Italy, southern Europe. We sequenced the total DNA from this tick sample, and, thanks to a dedicated bioinformatic pipeline, selectively assembled the genome of the bacterium, which represents the first one for <em>E. muris</em> from Europe. Phylogenetic and comparative genomic analyses were then performed. Accounting for tick species distribution, bird migratory routes, and molecular phylogeny of the bacterium, it is likely that this bird transported the tick to Italy from an endemic area of <em>E. muris</em>, such as eastern Europe.</div><div>In addition, comparative genomic analyses highlighted that <em>E. muris</em> and other <em>Ehrlichia</em> spp. display copy number variations in two families of membrane proteins, likely due to recent gene duplication, deletion and recombination events. These differences are probably a source of variability for surface antigens to evade host immunity, with a potential role in host adaptation and specificity. The present results underline the impact of migratory birds on the spread of tick-borne pathogens towards non-endemic areas, highlighting the need for further epidemiological surveillance at bird ringing stations in Italy, and advocating further investigations on possible local transmission of <em>E. muris</em> in competent mammalian hosts.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"15 6","pages":"Article 102409"},"PeriodicalIF":3.1,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142570158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Environmental and host factors underlying tick-borne virus infection in wild animals: Investigation of the emerging Yezo virus in Hokkaido, Japan","authors":"Mebuki Ito , Miku Minamikawa , Anastasiia Kovba , Hideka Numata , Tetsuji Itoh , Takuma Ariizumi , Asako Shigeno , Yuki Katada , Shiho Niwa , Yurie Taya , Yuto Shiraki , Gita Sadaula Pandey , Nariaki Nonaka , Ryo Nakao , Ryosuke Omori , Yuma Ohari , Norikazu Isoda , Michito Shimozuru , Toshio Tsubota , Keita Matsuno , Mariko Sashika","doi":"10.1016/j.ttbdis.2024.102419","DOIUrl":"10.1016/j.ttbdis.2024.102419","url":null,"abstract":"<div><div>Yezo virus (YEZV) is an emerging tick-borne virus that causes acute febrile illness. It has been continuously reported in patients and ticks in Japan and China since its first identification in Hokkaido, Japan. While serological tests have demonstrated that YEZV infections are prevalent in wild animals, such as raccoons (<em>Procyon lotor</em>), the determinants of infection in wild animals remain largely unknown. We examined the prevalence of YEZV in invasive raccoons, native tanukis (raccoon dogs, <em>Nyctereutes procyonoides albus</em>), and ticks in six study areas in Hokkaido between 2018 and 2023 to identify ecological factors underlying YEZV infection in wild animals. YEZV RNA fragments were detected in 0.22% of the 1,857 questing ticks. Anti-YEZV antibodies were detected in 32 of the 514 (6.2%) raccoon serum samples and in 5 of the 40 (12.5%) tanuki serum samples. Notably, the seroprevalence in raccoons varied significantly in one of the study areas over the years, that is, 0.0%, 60.0%, and 28.6% in 2021, 2022, and 2023, respectively, implying the temporary emergence of YEZV microfoci. By analyzing the tick load and YEZV seropositivity in raccoons in a field-based setting, we found a positive correlation between adult <em>Ixodes ovatus</em> load and YEZV-antibody positivity, highlighting the importance of <em>I. ovatus</em> in YEZV infection in wild animals. We also explored the environmental and host factors influencing YEZV seropositivity in raccoons and tanukis and found that landscape factors, such as the size of forest area around the trap site, were crucial for YEZV seropositivity in these animals. The significant variables for YEZV seropositivity in raccoons were partially different from those affecting tick infestation intensity in raccoons. The present results extend our understanding of tick-borne virus circulation in the field, emphasizing the unique ecology of the emerging YEZV.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"15 6","pages":"Article 102419"},"PeriodicalIF":3.1,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142744923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ana Cláudia Norte , El-Mustapha Laghzaoui , Andreia Guerreiro-Nunes , El Hassan El Mouden , Maria Sofia Núncio , Rita de Sousa , Isabel Lopes de Carvalho
{"title":"Molecular investigation of tick-borne pathogens from different regions of Morocco","authors":"Ana Cláudia Norte , El-Mustapha Laghzaoui , Andreia Guerreiro-Nunes , El Hassan El Mouden , Maria Sofia Núncio , Rita de Sousa , Isabel Lopes de Carvalho","doi":"10.1016/j.ttbdis.2024.102418","DOIUrl":"10.1016/j.ttbdis.2024.102418","url":null,"abstract":"<div><div>Tick-borne pathogens are a worldwide threat to public health that can only be mitigated by knowledge on tick-host associations coupled with surveillance of their infection by pathogenic microorganisms. This information is not equally available throughout tick vector distribution range and is deficient in some geographical areas. In this study we did a molecular survey of tick-borne pathogens associated with different tick species in Morocco. We analyzed four different species of <em>Hyalomma</em> (<em>Hyalomma aegyptium, Hyalomma anatolicum, Hyalomma dromedarii</em> and <em>Hyalomma impeltatum</em>) and <em>Rhipicephalus sanguineus</em> sensu lato ticks from four vertebrate hosts and from the vegetation. The most common tick species collected was <em>H. aegyptium</em> feeding on <em>Testudo graeca</em> tortoises, followed by <em>H. anatolicum</em> from the vegetation. <em>Hyalomma aegyptium</em> feeding on <em>T. graeca</em> was found infected with <em>Borrelia turcica</em>, representing the first detection for Western North Africa, and <em>Rickettsia sibirica</em> mongolitimonae, also detected for the first time in Morocco. <em>Rickettsia aeschlimannii</em> was also detected in <em>H. aegyptium</em> feeding on <em>T. graeca</em>. Additionally, <em>R. aeschlimannii</em> was detected in <em>H. anatolicum</em> from the vegetation, and <em>Rickettsia massiliae</em> in <em>R. sanguineus</em> s.l. from an Algerian hedgehog <em>Atelix algirus</em>. Because <em>H. aegyptium</em> are common parasites of <em>T. graeca</em> tortoises, and these animals are subjected to pet trade, it is important to evaluate the associated human health risks through regular surveillance and perform awareness campaigns for prevention of the general public.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"15 6","pages":"Article 102418"},"PeriodicalIF":3.1,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142744979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anna Kloc , Angelina Wójcik-Fatla , Piotr Paprzycki , Lech Panasiuk
{"title":"Transovarial transmission of Rickettsia spp., Francisella-like endosymbionts, and Spiroplasma spp. in Dermacentor reticulatus ticks","authors":"Anna Kloc , Angelina Wójcik-Fatla , Piotr Paprzycki , Lech Panasiuk","doi":"10.1016/j.ttbdis.2024.102421","DOIUrl":"10.1016/j.ttbdis.2024.102421","url":null,"abstract":"<div><div>Research on the transovarial transmission of pathogens whose reservoirs and vectors are ticks has led to an understanding of the mechanisms related to the circulation and persistence of selected microorganisms in natural foci. The primary aim of this study was to investigate the possibility of transovarial transmission of <em>Rickettsia</em> spp. in <em>Dermacentor reticulatus</em> ticks, and the influence of <em>Francisella</em>-like endosymbionts (FLEs) and <em>Spiroplasma</em> spp. on the efficiency of the egg-laying process and transmission of selected pathogens.</div><div>In total, 16,600 eggs were obtained under laboratory conditions from 55 females, with an average of 346 eggs per female. Adults, eggs, and hatched larvae were tested using polymerase chain reaction (PCR) for the presence of <em>Rickettsia</em> and endosymbionts.</div><div>DNA fragments of <em>Rickettsia</em> spp. were found in females (56.4 %) and in pools of eggs (72.9 %) and larvae (62.4 %). FLEs and <em>Spiroplasma</em> endosymbionts were confirmed in females (80 % and 14.5 %, respectively), pools of eggs (81.6 % and 26.1 %, respectively), and larvae (82.7 % and 46.2 %, respectively). Transovarial transmission was confirmed in <em>Rickettsia raoultii</em>, FLEs, and <em>Spiroplasma ixodetis</em>. No correlation was observed between the occurrence of individual endosymbionts and the efficiency of egg laying and transovarial transmission in <em>Rickettsia</em> spp.</div><div>In conclusion, transovarial transmission of <em>Rickettsia</em> spp., FLEs and <em>Spiroplasma</em> spp. in <em>D. reticulatus</em> plays an important role in their persistence and circulation in the environment. However, further research is required on this topic.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"15 6","pages":"Article 102421"},"PeriodicalIF":3.1,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142796371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Joris Koetsveld , Alex Wagemakers , Matthijs Brouwer , Bob de Wever , Ankje de Vries , Steven van Gucht , Anita Buskermolen , Diederik van Beek , Hein Sprong , Joppe W. Hovius
{"title":"Limited evidence of infection with other tick-borne pathogens in patients tested for Lyme neuroborreliosis in the Netherlands","authors":"Joris Koetsveld , Alex Wagemakers , Matthijs Brouwer , Bob de Wever , Ankje de Vries , Steven van Gucht , Anita Buskermolen , Diederik van Beek , Hein Sprong , Joppe W. Hovius","doi":"10.1016/j.ttbdis.2024.102415","DOIUrl":"10.1016/j.ttbdis.2024.102415","url":null,"abstract":"<div><div><em>Ixodes ricinus</em> is the main vector of the causative agents of Lyme neuroborreliosis. This tick species can also transmit tick-borne encephalitis virus (TBEV), spotted fever group (SFG) <em>Rickettsia</em> and <em>Borrelia miyamotoi</em> to humans<em>.</em> These tick-borne pathogens are present in Dutch ticks and have also been associated with human neurological infections, but well characterized disease cases are seldom reported. We therefore assessed the evidence for TBEV, SFG <em>Rickettsia</em> or <em>B. miyamotoi</em> infection in clinically well-described patients suspected of Lyme neuroborreliosis.</div><div>We retrospectively included patients with specific predefined clinical criteria from patients that were tested for Lyme neuroborreliosis between 2010 and 2014 at an academic Lyme borreliosis Center. Serology was performed on available serum samples, and cerebrospinal fluid (CSF) was tested by molecular methods.</div><div>Out of 514 potentially eligible patients, 176 individual patients were included. None of CSF samples was positive for the tested tick-borne pathogens, except for one previously described patient with <em>Borrelia miyamotoi</em> disease (BMD). Serology revealed 27, 14 and three patients with antibodies against SFG <em>Rickettsia, B. miyamotoi</em> and TBEV, respectively. No distinctive clinical symptoms or signs could be associated with seropositivity against any of these tick-borne pathogens.</div><div>Apart from the previously published BMD case, we were unable to find convincing evidence of new cases of tick-borne encephalitis, spotted fever rickettsiosis or BMD in a cohort of patients suspected of Lyme neuroborreliosis. While antibodies against these tick-borne pathogens were detected, we could not associate these findings to clinical symptoms or signs. Therefore, prospective studies on humans with tick exposure are necessary to describe the prevalence, etiology and clinical symptoms of these tick-borne diseases other than Lyme borreliosis and tick-borne encephalitis.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"15 6","pages":"Article 102415"},"PeriodicalIF":3.1,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142693768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"New rules for the submission of review articles to Ticks and Tick-borne Diseases","authors":"Olaf Kahl , Ben Mans , Ard Nijhof","doi":"10.1016/j.ttbdis.2024.102393","DOIUrl":"10.1016/j.ttbdis.2024.102393","url":null,"abstract":"","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"15 6","pages":"Article 102393"},"PeriodicalIF":3.1,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142299401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Editorial Board reshuffle at Ticks and Tick-borne Diseases","authors":"Olaf Kahl , Ben Mans , Ard M. Nijhof","doi":"10.1016/j.ttbdis.2024.102414","DOIUrl":"10.1016/j.ttbdis.2024.102414","url":null,"abstract":"","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"15 6","pages":"Article 102414"},"PeriodicalIF":3.1,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142693765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}