Alexander W. Gofton , Makenna Short , Michelle Michie , Dakota Gallaway , Ina Smith , Kim Blasdell , Anjana Karawita , Melissa J. Klein , Catherine A. Herbert , Stephen C. Barker
{"title":"Exploring Borrelia in Australia: Isolation, genomic characterisation, and host and vector associations","authors":"Alexander W. Gofton , Makenna Short , Michelle Michie , Dakota Gallaway , Ina Smith , Kim Blasdell , Anjana Karawita , Melissa J. Klein , Catherine A. Herbert , Stephen C. Barker","doi":"10.1016/j.ttbdis.2025.102505","DOIUrl":"10.1016/j.ttbdis.2025.102505","url":null,"abstract":"<div><div><em>Borrelia</em> are tick-borne spirochetes that include important pathogens that cause Lyme borreliosis and relapsing fevers. While multiple <em>Borrelia</em> species have been identified in Australia, further research is needed to understand their ecological roles and potential zoonotic risks. This study aimed to isolate and characterise two Australian <em>Borrelia</em> species—<em>Borrelia tachyglossi</em> and <em>Borrelia</em> sp. HB—through <em>in vitro</em> culture, genomic sequencing, and molecular surveys of ticks and vertebrate hosts. Despite extensive efforts, <em>Borrelia</em> sp. HB could not be cultured from <em>Haemaphysalis bancrofti</em> ticks, and its prevalence in questing ticks was low (0.14 %). Additionally, molecular screening of 504 wildlife hosts found no evidence of <em>Borrelia</em> sp. HB infection, suggesting a cryptic or highly restricted enzootic cycle. In contrast, <em>B. tachyglossi</em> was successfully cultured from <em>Bothriocroton concolor</em> ticks collected from echidnas (<em>Tachyglossus aculeatus</em>), enabling complete genome sequencing. Complement-mediated bactericidal assays demonstrated that <em>B. tachyglossi</em> is highly susceptible to human innate immunity, indicating it is unlikely to be pathogenic. Molecular surveys of wildlife-associated ticks revealed a broad diversity of reptile-associated <em>Borrelia</em> species in monitor lizards and snakes, reinforcing the hypothesis that Australian <em>Borrelia</em> persist in host-specific enzootic cycles. Our findings confirm that <em>Borrelia</em> species in Australia belong exclusively to the relapsing fever and reptile-associated clades, with no evidence of <em>B. burgdorferi</em> sensu lato. These results improve our understanding of <em>Borrelia</em> diversity in Australia and highlight the need for further research into their ecology, vector competence, and evolutionary history.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 4","pages":"Article 102505"},"PeriodicalIF":3.1,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144338826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Subolesin gene structure and mRNA isoform diversity in South African R. microplus ticks: Relevance for understanding subolesin-based tick vaccines","authors":"Elsje Christine Rabie, Christine Maritz-Olivier","doi":"10.1016/j.ttbdis.2025.102502","DOIUrl":"10.1016/j.ttbdis.2025.102502","url":null,"abstract":"<div><div>Designing a universal vaccine against ticks, capable of protecting a wide range of species, has long been an appealing goal. One antigen that has been proposed for a universal tick vaccine is Subolesin. Despite its intracellular and mostly nuclear location, this antigen has seen some success in bovine vaccine trials. The mechanism behind the observed efficacy remains elusive and may be due to various isoforms being produced in tick cells. By means of RNA sequencing and mapping to the annotated genome of <em>R. microplus</em>, this study confirms the presence of a single <em>subolesin</em> gene along with four distinct transcripts, resulting in three protein variants. However, none of the putative protein variants have extracellular location signals or known functional motifs. Furthermore, this study offers insights into the antigenic diversity of Subolesin isoforms and their expression across multiple life stages in <em>R. microplus</em> ticks from South Africa. This study also raise the question regarding the contrast between Subolesin's nuclear location, function, and its observed efficacy in bovine vaccine trials as an antigen accessible to the host immune system. Future studies evaluating antisera cross-reactivity with other tick proteins is therefore essential to fully understand subolesin as a protective antigen.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 4","pages":"Article 102502"},"PeriodicalIF":3.1,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144330120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Diana Rueda-Ramírez , Sara Weilage , Anna Obiegala , Lidia Chitimia-Dobler , Martin Pfeffer
{"title":"First report of phoretic deutonymphs of Thyreophagus corticalis (Michael, 1885) (Acari: Acaridae) on Ixodes ricinus (Linnaeus, 1758) (Ixodida: Ixodidae)","authors":"Diana Rueda-Ramírez , Sara Weilage , Anna Obiegala , Lidia Chitimia-Dobler , Martin Pfeffer","doi":"10.1016/j.ttbdis.2025.102504","DOIUrl":"10.1016/j.ttbdis.2025.102504","url":null,"abstract":"<div><div>Phoretic deutonymphs of <em>Thyreophagus corticalis</em> (Michael, 1885) were found associated with a male and nymphs of <em>Ixodes ricinus</em> during a sampling conducted in May 2024 in the district of Reutlingen, Baden-Württemberg, Germany, using the flagging method. A total of six deutonymphs were detected on four of the 652 ticks collected at four out of 25 sampling sites, indicating a geographically restricted and low incidence. This account is the first report of a phoretic association of <em>T. corticalis</em> with <em>I. ricinus.</em> We consider this phoretic association likely to be coincidental, possibly resulting from the ticks coming into contact with organic or decaying material at these four sampling sites where <em>T. corticalis</em> populations occurred.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 4","pages":"Article 102504"},"PeriodicalIF":3.1,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144307208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Veronika Urbanová , Marie Vancová , František Kitzberger , Jiří Týč , Tomáš Bílý , Tereza Kozelková , Petr Kopáček , Daniel Sojka
{"title":"Ultrastructural changes in the midgut of Ixodes ricinus nymphs across feeding and digestion stages","authors":"Veronika Urbanová , Marie Vancová , František Kitzberger , Jiří Týč , Tomáš Bílý , Tereza Kozelková , Petr Kopáček , Daniel Sojka","doi":"10.1016/j.ttbdis.2025.102503","DOIUrl":"10.1016/j.ttbdis.2025.102503","url":null,"abstract":"<div><div>Ticks rely on host blood as their primary source of nutrients and energy. In hard ticks (Ixodidae), a single blood meal per life stage supports survival, metamorphosis, and, in females, egg production. The midgut, the major metabolic organ, is responsible for both digestion and nutrient storage. While previous studies have described tick midgut histology, many foundational works, often decades old, lacked modern histochemical, immunohistochemical, and high-resolution imaging techniques. Moreover, inconsistent nomenclature of midgut cells across species complicates comparative analyses. We herein chronologically examined structural changes in <em>Ixodes ricinus</em> nymphal midgut tissue before, during, and after feeding. Using immunofluorescence and immunoelectron microscopy, we monitored lipid droplet dynamics and the uptake of blood-derived proteins, including hemoglobin and serum albumin. To further investigate endocytic processes, we employed serial block-face scanning electron microscopy and TEM tomography, focusing on midgut samples from nymphs fed for 48 h. These approaches allowed us to visualize in 3D hemoglobin and albumin uptake from the gut lumen and their intracellular distribution within the nymphal caecum and midgut cells. Our findings enhance the understanding of tick gut cell biology, particularly nutrient processing and energy metabolism, providing a foundation for future research on tick physiology and vector competence.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 4","pages":"Article 102503"},"PeriodicalIF":3.1,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144298992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Manja Zimmermann , Gabriele Margos , Christine Hartberger , Reto Lienhard , Anna J. Henningsson , Malin Lager , Mateusz Markowicz , Anna-Margarita Schötta , Andreas Sing , Benoit Jaulhac , Per-Eric Lindgren , Alje P. van Dam , Joppe W.R. Hovius , Volker Fingerle
{"title":"The real-time PCR targeting the phage terminase (terL) is not suitable for diagnostics of human Borrelia infections in Europe","authors":"Manja Zimmermann , Gabriele Margos , Christine Hartberger , Reto Lienhard , Anna J. Henningsson , Malin Lager , Mateusz Markowicz , Anna-Margarita Schötta , Andreas Sing , Benoit Jaulhac , Per-Eric Lindgren , Alje P. van Dam , Joppe W.R. Hovius , Volker Fingerle","doi":"10.1016/j.ttbdis.2025.102488","DOIUrl":"10.1016/j.ttbdis.2025.102488","url":null,"abstract":"<div><div>Bacteria of the <em>Borrelia burgdorferi</em> sensu lato (sl) species complex can cause Lyme borreliosis (LB) in humans. PCR plays an important role in the diagnosis of many infectious diseases but it is used auxiliary in LB diagnostics. Here, we re-analysed a previously published real-time PCR targeting the multicopy gene of the large subunit of phage terminase (<em>terL</em>) in <em>Borrelia</em>. We analysed cultured material of <em>Borrelia burgdorferi</em> sl species, serum and clinical tissue samples of LB patients. PCR conditions were as previously described by Shan et al. 2021 but we also investigated PCR modifications.</div><div>PCR on cultured specimens showed that whilst all samples of <em>B. burgdorferi</em> sensu stricto (ss) gave a positive result, not all isolates of <em>Borrelia</em> species causing LB in Europe (i.e. <em>B. afzelii, B. garinii</em>) were detected by the <em>terL</em> PCR. Only slight differences in Ct values were detected between PCR runs using the original ZEN/IFBQ double quencher probe compared to other double quencher probes or single quencher probes. Contrary to the hypothesis expressed by the authors of the original paper that the PCR could detect phage DNA in serum, our data show that the <em>terL</em> PCR was negative on all tested serum samples of individuals diagnosed with proven LB. Furthermore, using patient’s tissue samples not all infections with <em>B. afzelii</em> or <em>B. garinii</em> were detected, similar to the results obtained with cultured material or serial DNA dilutions of <em>Borrelia</em> species. We conclude, that the <em>terL</em> PCR in its current form is unsuitable for LB diagnosis in Europe.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 4","pages":"Article 102488"},"PeriodicalIF":3.1,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marcos Antonio Bezerra-Santos , Filipe Dantas-Torres , Nicola Pugliese , Mara Miglianti , Wafa Rhimi , Claudia Cafarchia , Domenico Otranto
{"title":"Susceptibility of Rhipicephalus rutilus ticks from dogs to different acaricides","authors":"Marcos Antonio Bezerra-Santos , Filipe Dantas-Torres , Nicola Pugliese , Mara Miglianti , Wafa Rhimi , Claudia Cafarchia , Domenico Otranto","doi":"10.1016/j.ttbdis.2025.102493","DOIUrl":"10.1016/j.ttbdis.2025.102493","url":null,"abstract":"<div><div>Brown dog ticks (<em>Rhipicephalus sanguineus</em> sensu lato) are widespread ectoparasites of dogs and may also infest other vertebrate hosts, including humans. The control of these ticks is primarily carried out using acaricides. In this study, we assessed the susceptibility of <em>Rhipicephalus rutilus</em> to different acaricides (i.e., amitraz, fipronil, ivermectin, and permethrin). Engorged female ticks (<em>n</em> = 36) were divided into three groups based on their origin (i.e., G1 – untreated dogs from a private shelter; G2 – permethrin-treated private dog shelter; and G3 - fipronil, amitraz, and (<em>S</em>)-methoprene treated owned dogs) and kept under controlled temperature and humidity for oviposition. The acaricidal effects of amitraz (AMZ), fipronil (FIP), ivermectin (IVM), and permethrin (PTR) against <em>R. rutilus</em> were evaluated using the larval packet test, with subgroups of tick larvae in each experimental assay. Our data indicate that <em>R. rutilus</em> larvae from all dog groups were susceptible to IVM. In particular, larvae from G1 were apparently susceptible to IVM and PTR, and tolerant to AMZ and FIP; larvae from G2 were susceptible to FIP and IVM and resistant to AMZ and PTR, while larvae from G3 were susceptible to AMZ, PTR and IVM, and resistant to FIP. These results confirm the occurrence of resistance to AMZ, PTR, and FIP in <em>R. rutilus</em> larvae from southern Italy. This suggests the need to monitor acaricide resistance in brown dog ticks in southern Europe to develop better strategies for the long-term control of ticks in this region.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 4","pages":"Article 102493"},"PeriodicalIF":3.1,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144229463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maggy Jouglin , Barbara Blanc , Alice Brunet , Katia Ortiz , Laurence Malandrin
{"title":"Anaplasma capra and Haemaphysalis concinna: Investigating a potential vector relationship in a wildlife reserve","authors":"Maggy Jouglin , Barbara Blanc , Alice Brunet , Katia Ortiz , Laurence Malandrin","doi":"10.1016/j.ttbdis.2025.102500","DOIUrl":"10.1016/j.ttbdis.2025.102500","url":null,"abstract":"<div><div>Recently, <em>Anaplasma capra</em>, a new member of the Anaplasmataceae, has been described in Asia and Europe. This pathogen infects a range of hosts, including small ruminants, cervids, and humans, and has been detected across several tick genera. In this study, we aimed to identify potential transmission vectors of <em>A. capra</em> by screening questing ticks from a wild fauna reserve where it had previously been detected in its red deer (<em>Cervus elaphus</em>) and swamp deer (<em>Rucervus duvaucelii</em>) populations. DNA of <em>Anaplasma capra</em> was sought in the dissected salivary glands of 198 adult questing <em>Haemaphysalis concinna</em> and 74 adult questing <em>Haemaphysalis inermis</em> ticks, which were collected from vegetation by visual inspection. <em>Anaplasma capra</em> was detected in the salivary glands of a single female <em>H. concinna</em>, suggesting potential vector competence for this pathogen. Sequences of the gltA and 16S rRNA genes from this sample were identical to those previously obtained from deer blood samples within the reserve. We also confirmed the circulation of <em>A. capra</em> in additional red deer within the reserve.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 4","pages":"Article 102500"},"PeriodicalIF":3.1,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Héloïse Duchêne , Albert Agoulon , Nathalie de la Cotte , Claire Bonsergent , Maggy Jouglin , Barbara Blanc , Alice Brunet , Katia Ortiz , Suzanne Bastian , Laurence Malandrin
{"title":"Sympatric occurrence of Ixodes ricinus, Haemaphysalis concinna and Haemaphysalis inermis in a wild fauna reserve","authors":"Héloïse Duchêne , Albert Agoulon , Nathalie de la Cotte , Claire Bonsergent , Maggy Jouglin , Barbara Blanc , Alice Brunet , Katia Ortiz , Suzanne Bastian , Laurence Malandrin","doi":"10.1016/j.ttbdis.2025.102491","DOIUrl":"10.1016/j.ttbdis.2025.102491","url":null,"abstract":"<div><div>Wildlife reserves represent confined ecosystems with a high concentration of non-native animal species. The <em>Réserve Zoologique de la Haute Touche</em>, a unique forested environment, houses approximately 50 species, primarily Artiodactyla and Perissodactyla. We conducted a comprehensive tick survey within the reserve in 2017, collecting ticks from vegetation by flagging (outside enclosures on 101 sampling points in May and September, inside 21 enclosures in May), by visual search outside enclosures in May, and directly on animals captured for routine veterinary interventions, over four consecutive years (2015–2018).</div><div>A total of 13,038 questing ticks, representing seven species, were collected via flagging outside and inside enclosures. <em>Ixodes ricinus</em> (88.9%), <em>Haemaphysalis concinna</em> (10.1 %), and <em>Haemaphysalis inermis</em> (1 %) were the dominant species, with all three parasitic life stages of these species found in May. The less common species were <em>Ixodes acuminatus</em> (2 nymphs), <em>Ixodes frontalis</em> (2 nymphs), <em>Dermacentor reticulatus</em> (3 adults), and <em>Dermacentor marginatus</em> (1 adult). <em>Ixodes ricinus</em> was ubiquitous throughout the reserve, outside and inside enclosures, at nearly all sampling sites (100/101 and 9/21 enclosures), followed by <em>H. concinna</em> (78/101 sites and 6/21 enclosures) and <em>H. inermis</em> (49/101 sites and 1/21 enclosures). Tick densities varied greatly with peak densities reaching 1221 <em>I. ricinus</em> nymphs per 100 m² and 46 <em>I. ricinus</em> adults per 100 m² in May. <em>Haemaphysalis concinna</em> densities reached 124 nymphs per 100 m². Visual searches for adult ticks on vegetation revealed statistically different proportions of these three species between different areas of the reserve, with <em>H. inermis</em> reaching 40.5 % of the collected adults in a specific area. Enclosures housing roe deer (<em>Capreolus capreolus</em>) and red deer (<em>Cervus elaphus</em>) exhibited the highest tick abundance on vegetation. Feeding ticks, including <em>I. ricinus</em> (<em>n</em> = 53), <em>H. concinna</em> (<em>n</em> = 26), and <em>D. reticulatus</em> (<em>n</em> = 1), were collected from 15 animals of six ruminant species.</div><div>This study represents the first documented sympatric occurrence of <em>I. ricinus, H. concinna</em>, and <em>H. inermis</em> in France, and the first description of <em>Haemaphysalis</em> species within a zoological reserve. The potential for pathogen transmission by these three generalist species and especially <em>Haemaphysalis</em> species (paucity of data) warrants further investigation.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 4","pages":"Article 102491"},"PeriodicalIF":3.1,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144212850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sophie E. Müller , Sophie Schneitler , Sabine Zange , Maximilian Linxweiler , Arne Simon , Lorenz Thurner , Sören L. Becker
{"title":"Clinical characteristics of and diagnostic approaches to human Francisella tularensis infection: a retrospective, monocentric case study from Germany","authors":"Sophie E. Müller , Sophie Schneitler , Sabine Zange , Maximilian Linxweiler , Arne Simon , Lorenz Thurner , Sören L. Becker","doi":"10.1016/j.ttbdis.2025.102492","DOIUrl":"10.1016/j.ttbdis.2025.102492","url":null,"abstract":"<div><div><em>Francisella tularensis</em>, the causative agent of tularemia, poses a challenge for diagnosis and treatment due to its diverse clinical presentations and low incidence. Hence, the awareness among clinicians is comparatively low. This study reports the clinical characteristics, diagnostic approaches, and treatment outcomes of tularemia cases at one tertiary center in Germany over a 12-yearperiod.</div><div>This retrospective monocentric case series considered all tularemia cases diagnosed at Saarland University Medical Center in Homburg, Germany between January 2013 and December 2024. Cases were identified from electronic medical records, and the certainty of tularemia was graded as definite, probable and possible infection, based on results of serology, polymerase chain reaction (PCR) assays, or blood cultures. Clinical data were extracted from patient records and supplemented by follow-up information from the clinicians.</div><div>We identified 14 tularemia cases, including 6 definite as well as 3 probable and 5 possible cases. The clinical presentation was highly variable, with the (ulcero-)glandular form being the most common entity (10/14). Invasive diagnostics or surgery were required in eleven out of 14 patients. Initial misdiagnosis was common, leading to delayed diagnosis and multiple courses of ineffective antibiotics. Definite treatment included fluoroquinolones or doxycycline, and led to resolution of symptoms in most patients.</div><div>The varied clinical manifestations of tularemia, from classic (ulcero-)glandular forms to severe and atypical presentations illustrate its diagnostic and clinical complexity. Enhanced awareness and early consideration are crucial, especially in endemic areas or patients with anamnestic environmental exposures.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 4","pages":"Article 102492"},"PeriodicalIF":3.1,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144195438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Raksha V. Bhoora, Tshenolo V. Mbaba, Milana Troskie, Rebecca E. Ackermann, Nicola E. Collins
{"title":"Quantitative detection of Theileria haneyi in South African horses","authors":"Raksha V. Bhoora, Tshenolo V. Mbaba, Milana Troskie, Rebecca E. Ackermann, Nicola E. Collins","doi":"10.1016/j.ttbdis.2025.102487","DOIUrl":"10.1016/j.ttbdis.2025.102487","url":null,"abstract":"<div><div><em>Theileria haneyi</em> is an apicomplexan parasite closely related to <em>Theileria equi</em>, a known causative agent of equine piroplasmosis. The molecular distinction between these parasites relies on a nested polymerase chain reaction (PCR) assay, which has been reported to be unreliable. A recently reported indirect ELISA based on equi merozoite antigen 11 (Th<em>ema</em>-11) of <em>T. haneyi</em> can detect geographically diverse <em>T. haneyi</em> strains. Since the <em>ema</em>-11 gene is exclusive to <em>T. haneyi</em>, it was chosen as the target for developing a TaqMan minor groove binder (MGB™) quantitative real-time PCR (qPCR). Published <em>T. haneyi ema</em>-11 gene sequences were used to design primers to amplify the <em>ema</em>-11 gene, and <em>ema</em>-11 amplicons from South African samples were cloned and sequenced. An alignment of the South African <em>ema</em>-11 gene sequences with published <em>T. haneyi ema</em>-11 gene sequences enabled the identification of a conserved region for the design of the qPCR assay. The <em>T. haneyi ema</em>-11 (Th<em>ema</em>-11) qPCR assay was efficient, specific, and sensitive in detecting <em>T. haneyi ema</em>-11. The detection limit was determined to be 1.169 × 10<sup>–3</sup> % parasitized erythrocytes. The performance of the Th<em>ema</em>-11 qPCR assay was evaluated together with a <em>T. equi ema</em>-1-specific qPCR assay. <em>Theileria haneyi</em> was detected in 67.6 % of the South African field samples screened, while the occurrence of <em>T. equi</em> based on the quantitative amplification of the <em>ema</em>-1 gene was higher (91.8 %). Our results suggest that combined, the Th<em>ema</em>-11 and <em>T. equi ema</em>-1 qPCR assays could detect and differentiate between <em>T. haneyi</em> and <em>T. equi</em> infections.</div></div>","PeriodicalId":49320,"journal":{"name":"Ticks and Tick-borne Diseases","volume":"16 3","pages":"Article 102487"},"PeriodicalIF":3.1,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143937529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}