Tick Research Articles

Lyme disease chemoprophylaxis prescribing before and after pharmacist prescriptive authority in Nova Scotia

Background: Lyme disease is a bacterial infection transmitted to humans through bites from infected Ixodes species of ticks. Prophylaxis with a single dose of oral doxycycline following a bite from an infected tick reduces the risk of developing Lyme disease. Pharmacists in Nova Scotia (NS) were among the first in Canada to prescribe for this indication. The primary objective of this study is to describe experiences with pharmacist prescribing of prophylaxis after tick bites in NS. Methods: A retrospective cohort study was performed using health administrative data 16 months before and after pharmacists were authorized to prescribe Lyme disease chemoprophylaxis (August 1, 2021). All dispensations of a single dose of oral doxycycline from a community pharmacy in NS were included. Data collected included prescriber type, date, and county of dispensation. Comparisons of dispensations were completed before and after pharmacists gained prescriptive authority and relative to other prescribers. Dispensations were described descriptively. Results: Over the study period, 12,549 single-dose doxycycline prescriptions were dispensed in NS: 3900 prescriptions were dispensed before pharmacist prescribing authorization for this indication occurred and 8649 were dispensed after. Pharmacists prescribed 61.3% of all single-dose doxycycline prescriptions following implementation of prescribing authority. Discussion: An increase in single-dose doxycycline prescriptions was observed in NS. Pharmacists have become the primary prescribers for Lyme disease chemoprophylaxis in the province. Conclusion: Patients were willing to be assessed for chemoprophylaxis after tick exposure by pharmacists, and pharmacist prescribing for this indication suggests increased access to post-tick exposure care.

The natural history of Amblyomma maculatum sensu lato, a vector of Rickettsia parkeri rickettsiosis, in southern Arizona.

Amblyomma maculatum sensu lato (s.l.) is an ixodid tick found in the semi-arid southwestern United States and northern Mexico where it is a parasite of medical and veterinary significance, including as a vector for Rickettsia parkeri, a cause of spotted fever rickettsiosis in the Americas. To describe the comprehensive natural history of this tick, monthly small mammal trapping and avian mist netting sessions were conducted at sites in Cochise County Arizona, within the Madrean Archipelago region where human cases of R. parkeri rickettsiosis and adult stages of A. maculatum s.l. were previously documented. A total of 1949 larvae and nymphs were removed from nine taxonomic groups of rodents and ten species of birds and were used in combination with records for adult stages collected both from vegetation and hunter-harvested animals to model seasonal activity patterns. A univoltine phenology was observed, initiated by the onset of the annual North American monsoon and ceasing during the hot, dry conditions preceding the following monsoon season. Cotton rats (Sigmodon spp.) were significantly more likely to be infested than other rodent taxa and carried the highest tick loads, reflecting a mutual affinity of host and ectoparasite for microhabitats dominated by grass.

Longitudinal Follow-up Reveals Peripheral Immunological Changes Upon Tick Bite in a-Gal-Sensitized Individuals.

α-Gal syndrome is characterized by specific IgE (sIgE) antibodies to the carbohydrate galactose-α-1,3-galactose (α-Gal) and delayed onset of allergic symptoms after ingestion of mammalian meat. While tick bites are assumed to mediate sensitization, the immune response to tick bites has not yet been investigated. To investigate the peripheral immune response to tick bites in humans over time. In a longitudinal cohort study, immunological reactions associated with tick bites (Ixodes species) were analyzed within 1 day (V1), 2 weeks (V2), 1 month (V3), and 3 months (V4) after the occurrence of a bite. sIgE, sIgG, and sIgG subclass levels, as well as 10 cytokines, were quantified. Deep immune phenotyping was performed using mass cytometry. A total of 4 controls and 10 patients were bitten by a tick and followed up over 3 months. None of the controls developed sIgE to α-Gal, and sIgE increased in all patients from V1 until V2/V3, as did IL-8 levels. We noted a significant increase in CD19+ B cells and B-cell subpopulations, as well as a decrease in γδ CD56+ T cells in patients between V0 and V1. At V1, frequencies of plasmacytoid dendritic cells (pDCs) and γδ CD56+ T cells were lower in patients than in controls. Our study provides evidence of significant changes in several immune cell populations in α-Gal sensitized patients, along with increased levels of IL-8 and sIgE. This is the first exploratory study to investigate longitudinal peripheral immune profiles in patients and controls bitten by ticks.

Beware of hitchhiking ticks? Clarifying the variable roles of bird species in tick movement along migratory routes

Ticks are blood‐feeding parasites which act as major vectors for various pathogenic microorganisms affecting both animal and human health. Hard ticks are known to move passively (i.e. ‘hitchhike') on migratory birds as they transit between breeding and non‐breeding grounds. This potentially leads to exchange and establishment of non‐endemic tick species in novel environments. However, it is not yet clear if all migratory bird taxa play an equal role in movement of specific tick species, especially outside of medically important tick taxa. To clarify these interactions, we performed a systematic literature review regarding primary data of ticks moving on migratory birds within the African–Western Palearctic flyways. In total, 35 studies were found which showed 123 bird species from 37 families and 12 orders connected to potential movement of 30 tick species representing six genera (Amblyomma, Dermacentor, Haemaphysalis, Hyalomma, Ixodes, Rhipicephalus). Most tick species did not show high abundance for any bird species, or, if they did, only on very few. Only Ixodes ricinus and Hyalomma marginatum were estimated to be carried at above average burdens by multiple bird species. This could indicate an increased likelihood of these species to be moved during migration. Specific tick species or whole genera were only found in certain migratory seasons as expected based on their geographic distributions. Even so, species found in both migratory seasons did not differ in their estimated abundances on birds between seasons. This result could suggest that tick abundance on migrating birds is not always a direct result of geographic distribution and may suggest an understudied importance of stopover sites towards potential tick introduction or turnover. Taken together, the results presented here provide guiding information for future analyses integrating individual level variation into the current understanding of tick movement with migratory birds.

Lyme serology in non-endemic countries: Why do we request it and what do we find?

The primary objectives of our research were to analyze Lyme serology results from pediatric patients, identify the clinical reasons for ordering these tests, and assess the clinical relevance of the serology results in the context of Lyme disease. Our study, conducted at a reference pediatric hospital in a non-endemic region for Lyme disease, included all pediatric patients for whom Lyme serology was requested. ELISA and Western blot results were documented. Presenting complaints and findings at the time of admission were recorded. Diagnostic tests were categorized as first-step tests if conducted during the initial visit. Subsequent tests, sent due to the inability to establish a diagnosis based on the results of the first-line tests, were defined as second and third-step tests, respectively. 219 patients, for whom Lyme serology had been requested for varying reasons, were included in our study. The most prevalent complaints and indications observed in the presentations of patients with serology requests were as follows: headache(24.7%), paresis/paresthesia(14.6%), and painful or blurred vision(13.2%). Serology was primarily requested in the presence of neurological(59.4%) and ocular symptoms(13.2%). 68% of the tests were requisitioned during the initial consultation. Nevertheless, it was discerned that no patient received a diagnosis of Lyme disease. According to the guidelines, Lyme serology should only be performed when there is a realistic possibility of exposure to infected ticks, particularly in patients who have had untreated erythema migrans or those with a history of a tick bite presenting with unexplained joint or neurological symptoms. Our data, in line with these guidelines, suggests that unnecessary Lyme serology testing in non-endemic areas, where exposure is highly unlikely, may lead to false-positive results and unnecessary follow-up testing, as illustrated by the high rate of false-positive ELISAs in our cohort.

Assessment of Babesia ovis pathogenicity in goats: implications for transmission dynamics and host resistant

Babesia ovis, commonly associated with ovine babesiosis, poses a significant threat to sheep health, often resulting in severe clinical manifestations and high mortality rates. However, the impact of B. ovis on goats has remained uncertain, prompting us to investigate its pathogenicity in caprine hosts. Experimental infections using B. ovis-infected blood inoculation and infected tick infestation, were conducted on spleen-intact (n=5) and splenectomized (n=5) goats. The experimental infection was performed using fresh blood obtained from a B. ovis-infected splenectomized sheep. One spleen-intact sheep served as a control for the experimental infection with B. ovis-infected Rhipicephalus bursa ticks. While all experimentally infected sheep (#501, #575) displayed severe clinical symptoms and high parasitemia, goats exhibited resistance, showing no significant clinical manifestations or sustained parasitemia. Notably, B. ovis was detected in two spleen-intact goats via nested PCR, prompting further investigation into their role as reservoirs for tick-borne transmission. These goats were then infested with Babesia spp.-free R. bursa larvae (0.1 gr) and adults (50 females and 50 males) for transstadial and transovarial transmission experiments respectively. Results indicated that chronically B. ovis-infected spleen-intact goats are not significant sources for maintaining the tick-borne transmission cycle of the parasite. These findings highlight the differential susceptibility of goats to B. ovis infection compared to sheep and their limited role as reservoirs for parasite transmission. Understanding the role of goats in B. ovis transmission and their resistance mechanisms can inform effective control measures and reduce economic losses in affected regions. Further research into caprine babesiosis and host immunological responses is essential to fully elucidate their possible role as reservoirs of the parasite, and underlying mechanisms of host susceptibility and parasite pathogenesis.

Listeriosis of Sheep in the Conditions of the Nakhchivan Autonomous Republic and the Role of Ticks in Its Spread

Listeriosis is a dangerous disease. Ixodid ticks are natural carriers of listeria. The aim of the work is to study listeriosis in sheep in the Nakhchivan Autonomous Republic and the role of ixodid ticks in their spread. In 2022, studies were conducted in the Sharur, Babek, and Julfa districts. Ticks were 2collected twice a year: in spring (April-May) and autumn (September-October). The pathogen can be transmitted from generation to generation through transovarial and metamorphic pathways. The causative agent of listeria is H. anatolicumand H. asiaticum and can persist in the body of ticks for up to 18 months, and female ticks are able to transmit listeria transovarially from one stage of development to another during their development. It has been established that young sheep aged 8-14 months are more susceptible to infection with listeriosis.

First Cases of Transplacental Transmission of Anaplasma spp. in Gabon: Cases Reports and Brief Review of the Literature

Anaplasma spp. is an emerging human zoonosis, usually transmitted by tick bites. Human-to-human transmission is rare, and transplacental transmission is even less common. No cases of transplacental transmission have been previously reported.We report the cases of patients who were followed up for febrile syndrome diagnosed with maternal-fetal infection and treated with antibiotic therapy and hemodynamic correction. Investigation of the etiology revealed Anaplasma spp. in a neonatal infection.These cases prove that transplacental transmission of Anaplasma spp. is possible and that surveillance is important.

Rhipicephalus simus ticks: new hosts for phleboviruses.

Ticks are widespread arthropods that transmit microorganisms of veterinary and medical significance to vertebrates, including humans. Rhipicephalus simus, an ixodid tick frequently infesting and feeding on humans, may play a crucial role in transmitting infectious agents across species. Despite the known association of many Rhipicephalus ticks with phleboviruses, information on R. simus is lacking. During a study in a riverine area in Lusaka Zambia, ten R. simus ticks were incidentally collected from the grass and bushes and subjected to metagenomic next generation sequencing (mNGS) in 2 pools of 5. Analysis detected a diverse microbial profile, including bacteria 82% (32/39), fungi 15.4% (6/39), and viruses 2.6% (1/39). Notably, viral sequence LSK-ZM-102022 exhibited similarity to tick phleboviruses, sharing 74.92% nucleotide identity in the RdRp gene and 72% in the NP gene with tick-borne phlebovirus (TBPV) from Greece and Romania, respectively. Its RNA-dependent RNA polymerase (RdRp) encoding region carried conserved RdRp and endonuclease domains characteristic of phenuiviridae viruses. Phylogenetic analysis positioned LSK-ZM-102022 in a distinct but lone lineage within tick phleboviruses basal to known species like brown dog tick phlebovirus and phlebovirus Antigone. Pair-wise genetic distance analysis revealed similar findings. This study emphasizes the urgency of further research on the ecology, transmission dynamics, and pathogenic potential of LSK-ZM-102022 and related TBPVs, crucial for local and global preparedness against emerging tick-borne diseases.

Why an Integrated Approach to Tick-Borne Pathogens (Bacterial, Viral, and Parasitic) Is Important in the Diagnosis of Clinical Cases

Tick-borne diseases have emerged as a major global public health problem in recent decades. The increasing incidence and geographical dissemination of these diseases requires the implementation of robust surveillance systems to monitor their prevalence, distribution, and public health impact. It is therefore not unexpected that tick-borne pathogens coexist in the same vectors, but the interactions of these agents between vectors and vertebrate hosts, including humans, remain poorly understood. The impact of infection in humans extends to the diagnostic challenges that arise when the same symptomatology can be associated with any tick-borne pathogen, and therapeutic recommendations only focus on the major or best-known tick-borne diseases, ignoring other lesser-known or less prevalent infections. Both surveillance systems and the holistic diagnosis of tick-borne pathogens are necessary tools to address the emergence of vector-borne diseases. In this study, we will focus on the main tick-borne viral, bacterial, and parasitic diseases in Spain to reflect the need to establish syndromic diagnostics in samples from patients with a history of tick bites and symptomatology compatible with them. On the other hand, and highlighting this need, innovations in molecular techniques, syndromic surveillance, and surveillance programs for ticks and tick-borne pathogens with public health implications are expected to be developed.

Ecology and phenology of the bat tick Argas (Carios) dewae (Acari: Argasidae).

Although 12 soft tick species (Argasidae) are native to Australia, the ecology of most is poorly known. Argas dewae parasitizes several insectivorous bat species and has been recorded on humans. Therefore, understanding its ecology is crucial for wildlife health management and public health preparedness. To address this knowledge gap, A. dewae populations were monitored from 2 bat hosts (Chalinolobus gouldii and Austronomus australis) using bat boxes at 3 sites in Victoria, Australia, for 28 months (July 2005–December 2007). A phenological profile undertaken for A. dewae revealed that tick load on bat hosts increased throughout winter and peaked in the first month of spring, before collapsing and remaining low throughout the drier late spring and summer periods. There was also further investigation of the relationship between 2 response variables (tick infestation risk and tick load) and a range of explanatory variables (body condition index, sex, age class, bioseason, site, bat density per nest box). In C. gouldii, site was the only significant predictor of A. dewae infestation risk, while load was correlated with several variables including age class, sex, bioseason, roost density and body condition index. This paper also reports the first records of A. dewae from 6 bat species in 3 bat families (Miniopteridae: Miniopterus australis; Molossidae: A. australis; Vespertilionidae: Chalinolobus morio, Myotis Macropus, Vespadelus darlingtonia, Vespadelus regulus) and a second record of A. dewae from a human. The first distribution records are presented for A. dewae in South Australia, the Australian Capital Territory and Queensland.

Mining the secreted and membrane transcriptome of Hyalomma dromedarii ticks for identification of potential protective antigens.

Members belonging to the tick genus Hyalomma function as a multi-host reservoir for several pathogens and important parasites infesting large animals, such as camels, goats, cattle and sheep. In Egypt, there is a high risk of pathogen transmission as camels and cattle are imported from Sudan and Ethiopia and shipped to slaughterhouses and animal markets located in populated areas. Hyalomma dromedarii ticks are semi-desert vectors and, similar to other members of the genus Hyalomma, characterized by long-term feeding. During this process, different physiological, biochemical and immunological interactions occur within both the feeding ticks and their hosts. These biological changes affect the different tick developmental phases. The aim of this study was to explore the transcriptome of mixed messenger RNAs (mRNAs) collected from H. dromedarii eggs, larvae, nymphs and fed and unfed adults, using the Gateway cDNA library prepared in pCMV sport6.1 vector METHODS: The clones were sequenced and searched for potential secreted, membrane-associated or transmembrane (SMaT) sequences. The identified SMaT sequences were compared to the National Center for Biotechnology Information (NCBI) non-redundant protein sequence database using Blastx. Annotation and functional classification were achieved by comparison to sequences in the UniProtKB/Swiss-Prot and VectorBase databases and to the publicly available annotated proteomes of six hard tick species (H. asiaticum, Rhipicephalus sanguineus sensu lato, Dermacentor silvarum, Rhipicephalus microplus, Ixodes scapularis and Haemaphysalis longicornis) in addition to the published H. dromedarii sialotranscriptome. For the common sequences, we predicted the physicochemical properties, secondary structures and antigenicity of the fragments similar to matched sequences in the UniProtKB/Swiss-Prot database using three different methods. The quality-trimmed sequences from the cDNA library revealed 319 SMaT transcripts among 1248 sequenced clones. Annotation of the SMaT sequences using the UniProtKB/Swiss-Prot database revealed only 232 non-redundant sequences with at least one match. According to the UniProtKB/Swiss-Prot and Vectorbase databases, the SMaT sequences were either secreted (extracellular) (29 sequences) or cellular (transmembrane and membrane-associated) (203 sequences). These were classified into 10 functional classes: biogenesis (49 sequences), defense (9 sequences), development (36 sequences), signal transduction (28 sequences), transport (15 sequences), protein modification (33 sequences), homeostasis (6 sequences), metabolism (45 sequences) and miscellaneous/uncharacterized (11 sequences). A total of 60 sequences were shared between H. dromedarii SMaT, the sialotransciptome and six other hard tick species. The peptide fragments of these sequences that aligned to proteins from the UniProtKB/Swiss-Prot database were predicted to be promising epitopes and mapped to 10 functional classes at different ratios. Our immuno-informatics analysis identified 60 sequences common among hard tick species and encoded by H. dromedarii salivary glands. These annotated SMaT sequences of H. dromedarii will pave the way for the identification and discovery of novel potential protective antigens that are either secreted, membrane-associated or transmembrane.

A series of patients infected with the emerging tick-borne Yezo virus in China: an active surveillance and genomic analysis

Yezo virus (YEZV) is an emerging tick-borne pathogen, which was initially reported in Japan in 2021. Only one patient had been reported in China so far. We aimed to describe the epidemiological, clinical, and laboratory findings of a series of patients, and to characterise the viral genomes of YEZV. In this active surveillance and genomic analysis, we conducted active surveillance at Mudanjiang Forestry Central Hospital, Heilongjiang Province of northeast China. Participants were eligible for inclusion if they sought medical care for a recent tick bite between May 1 and July 31, in 2022 and 2023, and between May 1 and July 10, in 2024. We collected sera from participants to detect YEZV infection by meta-transcriptomic sequencing, real-time RT-PCR, and indirect immunofluorescence assay. We isolated YEZV by cell culture and characterised the pathogen by morphological and phylogenetic analyses. A series of 18 patients with YEZV infection (12 male and six female; median age 53 years, IQR 45-60) were identified among 988 participants. The patients presented with fever (18 patients, 100%), headache (ten patients, 56%), dizziness (nine patients, 50%), malaise (three patients, 17%), lumbago (three patients, 17%), and cough (three patients, 17%). Nine (50%) patients had rash around the tick bite site and four (22%) had lymphadenopathy. Nine (50%) patients had gastrointestinal symptoms, and five (28%) had neurological symptoms. We observed leukopenia in ten (63%) and thrombocytopenia in five (31%) of 16 assessed patients. Elevated hepatic transaminase concentrations were identified in 13 (72%) of all 18 patients, lactate dehydrogenase or α-hydroxybutyric dehydrogenase in nine (50%), serum amyloid protein A in 13 (72%), and hypersensitive C-reactive protein in ten (56%). Eight (7%) of 119 Ixodes persulcatus ticks removed from participants were positive for YEZV. Three YEZV strains were isolated from the sera of patients. Ten viral genomes were obtained from five patients, a blood-sucking I persulcatus removed from a participant, and four host-questing tick samples collected in the areas where patients were identified or in the adjacent region. Phylogenetic analyses revealed that YEZVs in either patients or ticks were divided into two clades, each with distinct mutations. Awareness of YEZV infection is important and clinicians should consider the virus when diagnosing patients with suitable symptoms. National Key Research and Development Program of China. For the Chinese translation of the abstract see Supplementary Materials section.

Borelioza z Lyme w Polsce w 2022 roku

IntroductionIn Poland, Lyme disease has been subject to mandatory reporting and registration since 1996, and following EU law, cases of neuroborreliosis have been reported to the European Centre for Disease Prevention and Control (ECDC) since 2019. Lyme disease is transmitted by ticks of the Ixodes genus, and humans become infected through the bite of an infected tick. Due to the varied symptoms, diagnosis can be difficult and usually involves two-stage serological diagnostics. The aim of the study was to assess the epidemiological situation of Lyme disease in Poland in 2022 compared to the situation in previous years.Material and MethodsThe epidemiological situation of Lyme disease in Poland was assessed on the basis of the data sent to NIPH NIH – NRI by voivodeship sanitary-epidemiological stations and published in the bulletin “Infectious diseases and poisoning in Poland in 2022”.ResultsIn 2022, 17 369 cases of Lyme disease were registered, including 776 hospitalizations. This was a significant increase in cases by 38.96% and hospitalizations by 88.81% compared to the previous year. The seasonality that characterizes Lyme disease was noticeable in individual quarters, i.e. an increase in the number of cases from 1 151 in Q1 to 7 267 in Q3 and a decrease in Q4 to 5 708. At the voivodeship level, the highest incidence was recorded in the Podlaskie (81.2 per 100 000), Małopolskie (79.8 per 100 000) and Lubelskie (76.8 per 100 000) voivodeships.ConclusionsThe epidemiological situation of Lyme disease is gradually returning to the state before the COVID-19 pandemic. The percentage of hospitalized cases increased slightly (from 3.3% in 2021 to 4.5% in 2022), which, combined with the increase in the number of cases, meant an increase in the number of hospitalizations due to Lyme disease by almost 89%. The highest incidence was consistently observed in the eastern part of Poland (Podlaskie, Warmińsko-mazurskie, Lubelskie voivodeships).

Tick Infestation and Molecular Detection of Tick-Borne Pathogens from Indian Long-Eared Hedgehogs (Hemiechinus collaris) in Pakistan

Hedgehogs can act as reservoirs for the transmission of tick-borne pathogens (TBPs) to domestic livestock, wild animals, and humans. Understanding host–tick dynamics is essential to evaluate the impact of TBPs. This study was conducted in Pakistan and aimed to determine the prevalence and species of TBPs in the blood and ticks of Indian long-eared hedgehogs captured from various environments. A total of 64 hedgehogs were captured to check for tick infestation. Tick species were identified morphologically and molecularly including ITS-2 region amplification by PCR and subsequent Sanger sequencing. Moreover, TBPs were identified in both ticks and the blood of hedgehogs through conventional PCR and sequencing, targeting the regions msp1b, 18S rRNA, and cytb for Anaplasma spp., Babesia spp., and Theileria spp., respectively. Out of 64 hedgehogs, 16 (25%) were found to be infested with ticks. Morphological and molecular analysis identified all 109 collected ticks as Rhipicephalus turanicus. Only one hedgehog (6.2%) was infected with A. marginale. From the tick samples, 3.7% tested positive for Theileria lestoquardi, 2.8% for Anaplasma marginale, and another 2.8% for Babesia bigemina. This study provides critical insights into circulating TBPs in this region and what possible role hedgehogs might play in disease maintenance for Anaplasma marginale while identifying multiple pathogens that are of concern to human and animal health.

Lyme borreliosis in Brazil: a critical review on the Baggio-Yoshinari syndrome (Brazilian Lyme-like disease).

SUMMARYLyme borreliosis or Lyme disease is the most frequently reported tick-borne disease in the Northern Hemisphere. In countries of the Southern Hemisphere, such as Brazil, since the early 1990s, some researchers have argued for the existence of an autochthonous Lyme-like borreliosis, known locally as the Baggio-Yoshinari syndrome (BYS), an alleged "Brazilian borreliosis" supposedly caused by a different strain of Borrelia burgdorferi and transmitted by hard ticks. Currently, the existence of BYS in Brazil is still accepted by a large part of the human health care workers, scientists, medical societies, and patients. In fact, this alleged "Brazilian borreliosis" has been the tick-borne zoonotic disease with the greatest number of reported cases and published studies in Brazil during this century, second only to Brazilian spotted fever. In this manuscript, we reviewed all manuscripts directly related to BYS that have been published in Brazil during the last 35 years. This analysis included 199 individual human cases that have been reported in Brazil since 1989, plus multiple studies on ticks, domestic, and wild animals. Our revision aimed to provide a critical opinion on whether the current published works allow healthcare workers, public health agencies, and patients to accept the existence of Lyme disease, BYS, or other Lyme borreliosis-related disease in Brazil. For this purpose, we evaluated the strengths and weaknesses of each published study, considering the diagnostic methods used, such as serological, microbiological, and molecular analyses. Based on these evaluations, we conclude that there is not enough evidence to support the occurrence of Lyme borreliosis in Brazil or that BYS (Brazilian Lyme-like disease) is caused by a bacterium of the genus Borrelia. This assumption is based on the inaccuracy, unreliability, and misinterpretation of the different diagnostic methods that have been used in Brazil. Recognizing the lack of technical evidence for the occurrence of Lyme borreliosis in Brazil has highly relevant implications. For example, it becomes imperative to raise awareness among the country's medical profession, as they have adopted unnecessary and extreme therapies recommended for patients with a supposed borrelial infection, including BYS, in Brazil. Finally, the technical analyses carried out in this study could be applied to other countries in the Southern Hemisphere (e.g., Argentina, South Africa, Australia), where cases classified and alleged as Lyme disease have been reported.

A higher infection rate of Toxoplasma gondii in soft ticks infesting domestic hens: A novel report from Pakistan

Ticks are the second most important hematophagous ectoparasites after mosquitoes and serve as vectors for various pathogens, transmitting them to wild and domestic animals, as well as humans. Argas persicus are the soft ticks that are known to parasitize domestic poultry. Hard ticks are known to be the reservoir of Toxoplasma (T.) gondii but limited such information is available for soft ticks. This study reports the molecular prevalence and phylogenetic analysis of T. gondii infecting Argas (A.) persicus ticks (N = 70), collected from four domestic poultry breeds in the Kurram District, Khyber Pakhtunkhwa, Pakistan, between June and August 2023. The results showed that 26 out of 70 (37 %) A. persicus samples tested positive for the ITS-1 gene of T. gondii. These findings were confirmed by the DNA sequencing and BLAST analysis of amplified amplicons. Phylogenetic analysis showed that Pakistani isolates were genetically diverse and clustered with isolates that were reported from birds and mammals from Pakistan, Tunisia, Malaysia, Brazil and Iraq.Risk factor analysis indicated that the prevalence of T. gondii was not associated with any specific poultry breed, sampling period, or the body temperature of the fowl hosts. Similarly parasite prevalence was not found associated with tick sex or their developmental stage but parasite infection rate varied with the feeding status of the ticks; highest T. gondii infection rate was observed in fully fed Argas persicus. In conclusion, this is the first report from Pakistan highlighting a high prevalence of T. gondii in A. persicus infesting domestic poultry suggesting a potential zoonotic risk to humans through the consumption of infected poultry. This data is confirming that in addition to oral ingestion of oocysts, T. gondii can be mechanically transmitted through soft ticks.

Prevalence and diversity of spotted fever group Rickettsia species in ixodid ticks from domestic dogs in Chad, Africa

Tick-borne pathogens in the genus Rickettsia are the causative agents of severe and potentially fatal spotted fever group (SFG) and typhus group diseases in dogs and humans. Climate, habitat, and land-use changes are impacting vector ranges, with expansions potentially resulting in novel pathogens being introduced into naïve locations. Despite the public health importance of SFG Rickettsia, there are relatively few data on the prevalence and diversity of rickettsial pathogens in sub-Saharan Africa. The aim of this study was to characterize the SFG Rickettsia prevalence and diversity in ixodid ticks (104 Amblyomma spp., 160 Rhipicephalus spp., and one Hyalomma truncatum) collected from domestic dogs in Chad, Africa. Ticks were screened for Rickettsia spp. using a nested PCR targeting the 17-kDa gene. Species identification was through bidirectional Sanger sequencing of the 17-kDa, ompA, ompB, and/or gltA gene targets. A total of 43.3 % (115/265) ticks were positive for Rickettsia spp. and six Rickettsia species were identified: R. africae, R. massiliae, R. conorii, R. felis, R. monacensis and Candidatus Rickettsia muridii. Seven additional samples were positive for Rickettsia of undetermined species. Rickettsia africae, an important zoonotic pathogen, was found in 81 % (79/97) of A. variegatum and 29 % (2/7) of an A. marmoreum complex species, a group that infests a wide range of birds and mammals, including humans. Finally, we detected a high diversity of Rickettsia spp., most of which were zoonotic, in Rh. muhsamae. Collectively these data indicate there is a risk of rickettsiosis in Chad and further studies on ticks and rickettsial pathogens in this region are warranted.

Temporal increase in ticks and pathogen prevalence in the small mammal part of the Lyme disease cycle in northern Europe

AbstractLyme disease is an emerging infectious disease and the most common vector‐borne zoonosis in the northern hemisphere. The pathogen that causes Lyme disease in Europe is vectored by the generalist tick Ixodes ricinus, and the emergence of Lyme disease is partly linked to how climate warming affects tick distribution and abundance. However, we lack long‐term data on tick infestations and infection prevalence in the main hosts involved in the transmission cycle. Here, we quantified the temporal trends (2014–2022) of I. ricinus infestations and the prevalence of Borrelia burgdorferi sensu lato in small mammalian hosts and linked annual variation to host abundance and climate in Norway. We found that tick infestations for both larvae (21% per year [95% CI 18–25]) and nymphs (18% [11–26]), and infection prevalence (14% [8–20]) increased over the period and were negatively associated with rodent abundance. Additionally, warmer years were associated with increased larval tick infestations on hosts. The combination of a temporal increase in both larval tick infestation and infection prevalence in hosts likely results in increased production of infected nymphs. Thus, we provide one mechanistic step toward understanding the Lyme disease emergence at northern latitudes of Europe.

Multi-season survey of ixodid tick species collected from domestic dogs in Chad, Africa

Multi-season survey of ixodid tick species collected from domestic dogs in Chad, Africa